# Which is better: P-47 or Fw-190?



## mosquitoman (Jun 3, 2005)

I just thought it was a closer match than the Spit/190 thread. Which one's better?


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## cheddar cheese (Jun 3, 2005)

Fw-190


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## plan_D (Jun 3, 2005)

The Fw-190 was better, in my opinion. Although, I think the late mark P-47Ms and Ns were probably better escort fighters because they out-ranged the Fw-190.


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## cheddar cheese (Jun 3, 2005)

I think a P-47N would be good match up for the Fw-190D-9


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## plan_D (Jun 3, 2005)

I would and I like the armament on the P-47 more. Eight .50s will rip anything to shreds.


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## cheddar cheese (Jun 3, 2005)

I agree in that respect, also is tougher as well. Sneaky feeling that the D-9 is more manouverable though.


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## FLYBOYJ (Jun 3, 2005)

Does anyone have stats on P-47 vs -190D kills?


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## DAVIDICUS (Jun 3, 2005)

This site features a head to head test of a captured FW-190 and a P-47. Scroll down to P47 VS: FW190.

http://www.lanpartyworld.com/ww2/alliedair.htm

The P-47 was outfitted with a toothpick propeller.

The FW-190 was the winner.

Francis Gabreski commented on how the P-47 stacked up against its opponents in an interview. (You can read this interview on the Stories forum under Interview With Francis Gabreski)

CUNNINGHAM: How did your P47s compare to the German fighters? 

GABRESKI: Well, Bob, it all depends on what P-47 you're talking about. The early P-47 - which was the basic airplane - had a very thin propeller, although it was a four-bladed propeller. It didn't have water injection. It didn't have all the niceties of the P-47D20 that came into the theater sometime in the latter part of, uh ... well, it was actually about March of 1944. So the improvement that we had (was) water injection, which gave you a power increase of from 52 inches of mercury to about 72 inches of mercury, which was a tremendous boost in power and performance. Then you had tremendous visibility with the teardrop canopy. You could cover your tail and look out freely without the crossbars kinda' restricting your vision. So I would say that the P-47I finally went down with on July 20, 1944, was one of the finest little airplanes that I have ever flown. It was more than a match for the Focke-Wulf 190. It was more than a match for the 109. I had absolutely no problem as long as I used water injection, and I used it quite frequently. We had water injection that would, with sustained power, keep us there for about three minutes up to five minutes, depending upon how you use it. But it gave us that tremendous edge that we needed against the German Luftwaffe.

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## FLYBOYJ (Jun 3, 2005)

DAVIDICUS said:


> This site features a head to head test of a captured FW-190 and a P-47. Scroll down to P47 VS: FW190.
> 
> http://www.lanpartyworld.com/ww2/alliedair.htm
> 
> ...



Great site Davidicus, but after reading that report I don't think the -190 is a clear "winner." There were many situations where the -47 out turned it, climbed and dived away from it. I think this report just verified what was already known about the earlier -47s. DIVE, DIVE, DIVE

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## plan_D (Jun 3, 2005)

The P-47N wouldn't have a tough time against any Fw-190A then. The Fw-190D would certainly be a different story though. A close call though. It certainly would not be easy pickings for either aircraft. 

One thing I am certain of though is the armament, it was much better for a dogfight on the P-47 than on the Fw-190. Eight Browning M3 .50cal against two MG151/20 and two MG131 in the D-9.


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## DAVIDICUS (Jun 3, 2005)

In addition, at very low altitude, the P-47 could hold its own. 

It's impressive to bear in mind that the test P-47 weighed about 5,000lbs more than the test FW-190.

I bet the paddle bladed P-47D was a real handful for the Luftwaffe per Gabreski's comments.


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## FLYBOYJ (Jun 3, 2005)

Agreed - and I think when the propellers were changed is when the -47 really started doing damage!


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## Soren (Jun 3, 2005)

A side-note: The Fw-190 used in that test, used a not-properly working engine. And AFAIK it was an A/8. 

At 0-7000 ft alt, the 190 would outturn the P-47D, and even more so at high speed. At 10.000 ft+ alt, the P-47 however becomes superior.

Against the Fw-190D-9, the P-47D didnt stand much chance in a dogfight. The Fw-190D-9 could outturn, out-climb, and out-roll the P-47D at all speeds, wich gives the D-9 an edge which would be allmost impossible for the P-47D to overcome. The fight would have to start high up, if the P-47 would be to stand much chance, and luckely that happened many times when escorting bombers.

As a dogfighter, the Fw-190 is clearly the superior airplane, whilst as an escort fighter the P-47D is superior.


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## FLYBOYJ (Jun 3, 2005)

Agree!


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## plan_D (Jun 3, 2005)

What about the P-47N?


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## FLYBOYJ (Jun 3, 2005)

plan_D said:


> What about the P-47N?



I think it would give a 190D a very good fight, each aircraft will have the edge in certain situations. Pilot skill will definitely come into play.


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## DAVIDICUS (Jun 3, 2005)

The P-47N could outperform the "D" model in all respects. The below excerpt concerns testing of the "N" model.

From: http://home.att.net/~historyzone/Seversky-Republic8.html 

Test comparisons were made with a P-47D-30-RE throughout the early portion of the evaluation period. Much to everyone’s surprise, the XP-47N, with its greater wingspan and higher weight actually proved to have better roll performance than the D model. At 250 mph TAS, the N attained a maximum roll rate just over 100 degrees/second. The P-47D-30-RE could manage but 85 degrees/second at the same speed. At higher speeds, the N widened the gap further. 

In mock combat with a P-47D-25-RE, the new fighter proved to be notably superior in every category of performance. In short, the XP-47 waxed the venerable D model regardless of who was piloting the older fighter. The new wing was part of this newfound dogfighting ability, however, the more powerful C series engine played a role too. The additional horsepower allowed the N to retain its energy better than the older Thunderbolt. 

Perhaps the greatest performance increase was in maximum speed. Though not as fast as the stunning P-47M, the heavier N was fully 40 mph faster than the P-47D-25-RE and could generate speeds 30 mph greater than its principal rival, the Mustang. Scorching along at 467 mph @ 32,000 ft., the N could not be caught by any fighter in regular service with any air force on earth with the single exception of its M model sibling. This combination of wing and engine had pushed the N model up to the top rank of the superlative prop driven fighters then in existence.

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## FLYBOYJ (Jun 3, 2005)

Another nice site Davy!


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## DAVIDICUS (Jun 3, 2005)

I love this picture. She was a B-I-G plane weighing in fully loaded at over 20,000lbs!


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## Erich (Jun 3, 2005)

the only stats with Jugs and Doras would be with the 8th AF 56th fg. Am sure there were very few incidents ..............


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## evangilder (Jun 3, 2005)

Nice pic, Davidicus!


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## Soren (Jun 3, 2005)

FLYBOYJ said:


> plan_D said:
> 
> 
> > What about the P-47N?
> ...



Well it wouldnt last a dogfight with the D-9 for long, but it could chicken out almost whenever it wanted.

At high alt I think the D-9 and -47N would be about equal in an overall point of view, but the -47N would be alot faster. At low alt the -47N better not get suckered into a close fight with the D-9, as its almost entirely doomed to fail. The D-9 still has all its previus advantages, and will be almost impossible to beat at low-med alt.

---------------------

Btw, very nice pic DAVID ! Color photo's of a -47 are always nice 8)


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## Nonskimmer (Jun 3, 2005)

I agree. Great pic, and a couple of great links. 
Thanks DAVIDICUS.


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## lesofprimus (Jun 3, 2005)

Seeing how this is all theoretical, I agree with Soren on all accounts.....

Now.... Armament... While Ill compromise and say I love the 8x .50's, what do u think the Dora would have been able to do to the -47 if it had machine guns instead of cannon....

Tickle its belly????

I think that one comes down to simple personal choice..... 20mm explosives or sheer volume of .50 lead....


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## Erich (Jun 3, 2005)

disagree if you will but every German pilot I have interviewed states they had the superior ammo and guns but not the A/C.

heck let's not go there ....


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## lesofprimus (Jun 3, 2005)

> every German pilot I have interviewed states they had the superior ammo and guns


I agree erich... The ones I have talked to, and have read about, all thought the same thing.... 


> but not the A/C.


Until the Dora and the -152H and C came out.... But as we all know, too little too late......


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## Soren (Jun 3, 2005)

Erich said:


> disagree if you will but every German pilot I have interviewed states they had the superior ammo and guns but not the A/C.





What I most commonly hear from vets, is that it wasnt the A/C's quality or maneuverability that was the problem, but the high alt performance. 

Insufficient Pilot training, fuel shortages, and low high alt performance were the main problems. The maneuverability and ammunition of the "fighters" was excellent.

This is what I most commonly get ot hear from "Fighter-pilots" atleast. I've never heard them complain about A/C ammunition or maneuverability as a problem.


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## DAVIDICUS (Jun 3, 2005)

The M3's appear to have been installed on the P-47N's stationed on LeShima.

Those M3's afforded an extra 350rpm over the M2's. (M3 - 1,200rpm / M2 - 850rpm using estimates at the high end)

P-51's had no problem tearing up their adversaries with six M2's throwing just 85 rounds per second.

A P-47N outfitted with M3's could throw 160 rounds per second.


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## Soren (Jun 4, 2005)

DAVIDICUS said:


> The M3's appear to have been installed on the P-47N's stationed on LeShima.
> 
> Those M3's afforded an extra 350rpm over the M2's. (M3 - 1,200rpm / M2 - 850rpm using estimates at the high end)
> 
> ...



Enough to cut any axis fighter to pieces. However I would still prefer D-9's armament if up against a -47 ! I'm confident that big bird could take a hell of alot of .50's !


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## FLYBOYJ (Jun 4, 2005)

I don't know Soren, wasn't the D-9s tail wood? I hate to have 50s going through my empannage! (What the hell did I just say?)


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## Erich (Jun 4, 2005)

no it was made of metal and there was some consideration on the last batch to use wood. The TA 152 was in the same boat with materials. The 109K-4's tailsection was of wood though 

the D-9 was mince meat in front of .50's, but in numerous older postings I have given credence to the firepower of 2cm and 3cm Minen Geschoss


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## delcyros (Jun 4, 2005)

0.50 cal. M3 are no common equippment at the ETO in general. A few have been in PTO I think, but I don´t even know of a single ETO 0.50 M3 equipped plane (maybe there are). And the 0.50 M2 is not that impressive, anyway the HE rounds of 20mm MG 151/20 and 30mm MK 108 are more than enough to deal with a P-47. They are less probable to hit but less hits are needed to ensure destruction, also. Who wins?
If you want to initiate a "what if" with the 0.50 M3, than we have some MG213B/20 mm, also and this can be regarded as the ultimative air to air gun.
Anyway, the P-47N has a considerable speed advantage over the D-9 and can hold it´s top speed for a longer time.
This works positively for the energy managemant of the P-47N.


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## Soren (Jun 4, 2005)

FLYBOYJ said:


> I don't know Soren, wasn't the D-9s tail wood? I hate to have 50s going through my empannage! (What the hell did I just say?)



FLYBOYJ i think you missunderstood me  

When I said "BIG bird" i meant the -47, not the D-9. Which is why I said i would prefer the D-9's armament if up against the -47, as .50's most likely aint gonna do much damage to a -47.


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## FLYBOYJ (Jun 4, 2005)

OH - ok


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## Erich (Jun 4, 2005)

yes HE 13mm would do some damage to the P-47.

as I said earlier I am rather doubtful any P-47 ran up against the Dora, the topic should read the Jug bubble or razorback type against the Fw 190A variants


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## Soren (Jun 4, 2005)

> yes HE 13mm would do some damage to the P-47.



Yes, but U.S. .50's wouldnt, or yes they would, but it wouldnt be much. 



> as I said earlier I am rather doubtful any P-47 ran up against the Dora, the topic should read the Jug bubble or razorback type against the Fw 190A variants.



Agreed.


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## Soren (Jun 4, 2005)

FLYBOYJ said:


> OH - ok



No problem FLYBOYJ


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## DAVIDICUS (Jun 4, 2005)

I have read that the D-9 could only muster *397*mph at 32,000ft. (In fact, the source I read states that its speed decreased from a high of 426mph at 21,650ft [http://www.csd.uwo.ca/~pettypi/elevon/baugher_other/fw190d.html]) If that is the case, I think the P-47N could easily handle the D-9 at higher altitudes. The P-47N could do *467*mph at 32,000ft.

I have never been able to find climb rate information on the P-47N. I have seen climb figures for the P-47M which had the same souped up power plant as the "N" model. 

From: http://www.geocities.com/pentagon/quarters/9485/P-47M.html

_Climb, at max. gross weight (including three 75 gallon drop tanks): 4.9 minutes to 15,000 feet at 2,600 rpm (1700 hp). Reportedly, the "M" could reach 20,000 feet in 5.7 minutes at military power (2,100 hp @ 2,800 rpm). 20,000 feet in 4.75 minutes in WEP (2,800 hp @ 2,800 rpm). This is with full internal fuel and ammo. No external stores or drop tanks. In other words, normal load, clean configuration._

Of course, the "M" model was lighter. Additionally, however, I don't know how the P-47N's new and larger wing might have influenced its ability to climb.


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## DAVIDICUS (Jun 4, 2005)

From: http://www.geocities.com/pentagon/quarters/9485/P-47M.html

P-47N in ass-whoop mode.


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## Soren (Jun 4, 2005)

DAVIDICUS said:


> I have read that the D-9 could only muster *397*mph at 32,000ft. (In fact, the source I read states that its speed decreased from a high of 426mph at 21,650ft [http://www.csd.uwo.ca/~pettypi/elevon/baugher_other/fw190d.html]) If that is the case, I think the P-47N could easily handle the D-9 at higher altitudes. The P-47N could do *467*mph at 32,000ft.
> 
> I have never been able to find climb rate information on the P-47N. I have seen climb figures for the P-47M which had the same souped up power plant as the "N" model.
> 
> ...



Holy mother of mary !  Those climb figures have got to be off !  

The -47N certainly would outrun the D-9, but outclimb it, no way !


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## DAVIDICUS (Jun 4, 2005)

Those are figures for the "M" not the "N" model. I don't think they are off. Consider that the XP-47J also had that same "C" series powerplant. It's performance was as follows:

From: http://home.att.net/~historyzone/Seversky-Republic7.html

_The XP-47M was, essentially, developed collaterally with the XP-47J. The J was fitted with a high output version of the P&W R-2800. Specifically, the R-2800-57. This engine made 2,800 hp @ 2,800 rpm at 35,000 feet. This is in War Emergency Power. The aircraft actually attained 507 mph at an altitude of 34,300 feet. 2,800 hp is 133% of rated power. At military power (100%), the XP-47J could sustain 470 mph. 435 mph was attained at 81% of it's rated power (1,700 hp). All performance figures were obtained at 34,300 feet. The J model was an especially good climbing fighter too. It had a climb rate at sea level of 4,900 fpm. At 20,000 feet, it was still rocketing up at 4,400 fpm, and got there in 4 minutes, 15 seconds. Time to 30,000 feet was only 6 minutes, 45 seconds. Now that's an interceptor! Yet it had a usable range of 1,075 miles. Rather impressive performance. Nor was this a stripped down hotrod. It was fully armed and carried ballast in the wings equal to 267 rds per gun. The aircraft was flown to a height of 46,500 feet and was capable of a bit more._

I offered ther "M" data purely for speculative purposes as I can't seem to locate any data on the "N" climb rates.


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## syscom3 (Jun 4, 2005)

Thought you guys would like this pix...... five P47's patrolling the sky's over Chino, California.

You dont see this happen everyday.

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## Nonskimmer (Jun 4, 2005)

Nice! Did you take that yourself?


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## DAVIDICUS (Jun 4, 2005)

Be still my beating heart!

What a treat that must have been.

On a related note, on September 10th and 11th, there will be a reunion of P-47's at Lunken Airshow in Cincinnatti, Ohio. The event is called, "Can You Hear The Thunder, A Gathering of P-47's"

I believe they are expecting six or seven aircraft and some will be flying. In addition, there will be a P-47 ace there too.


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## syscom3 (Jun 4, 2005)

I took these pictures a few weeks ago at the Chino airshow.

Even when they're on the ground they look deadly


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## Soren (Jun 4, 2005)

> Those are figures for the "M" not the "N" model. I don't think they are off.


 
Sorry DAVID, but they are infact (from what I can tell) very much off. 



> Consider that the XP-47J also had that same "C" series powerplant. It's performance was as follows:
> 
> From: http://home.att.net/~historyzone/Seversky-Republic7.html
> 
> _The XP-47M was, essentially, developed collaterally with the XP-47J. The J was fitted with a high output version of the P&W R-2800. Specifically, the R-2800-57. This engine made 2,800 hp @ 2,800 rpm at 35,000 feet. This is in War Emergency Power. The aircraft actually attained 507 mph at an altitude of 34,300 feet. 2,800 hp is 133% of rated power. At military power (100%), the XP-47J could sustain 470 mph. 435 mph was attained at 81% of it's rated power (1,700 hp). All performance figures were obtained at 34,300 feet. The J model was an especially good climbing fighter too. It had a climb rate at sea level of 4,900 fpm. At 20,000 feet, it was still rocketing up at 4,400 fpm, and got there in 4 minutes, 15 seconds. Time to 30,000 feet was only 6 minutes, 45 seconds. Now that's an interceptor! Yet it had a usable range of 1,075 miles. Rather impressive performance. Nor was this a stripped down hotrod. It was fully armed and carried ballast in the wings equal to 267 rds per gun. The aircraft was flown to a height of 46,500 feet and was capable of a bit more._



Im afraid this seems to be yet another case of a biased website sending out wrong data. 

Anyway as I found the data on your presented website very suspicious, I went looking in some of my books on the P-47 and its variants, and this is what I found:

_Performance of the P-47M-1-RE:

Engine: Pratt Whitney R-2800-57(C) 2800hp /w water injection
Max. Speeds: 400 mph at 10,000 ft, 453 mph at 25,000 ft, and 470 mph at 30,000 ft. 
Initial climb rate:*3500 ft/min at 5000 feet, 2650 ft/min at 20,000 ft.* 
Wing area: 308 sq.ft.
Weights: 10,432 lbs empty, 13,275 lbs loaded, 15,500 lbs maximum. 
Armament: Six or eight 0.50-inch machine guns with 267 or 425 rpg. 
Range (clean): 560 miles at 10,000 feet. _

_Performance of the P-47N:

Engine: Pratt Whitney R-2800-57(C)/-77 2800hp /w water injection.
Max. Speeds: 397 mph at 10,000 ft, 448 mph at 25,000 ft, and 460 mph at 30,000 ft.
Initial climb rate:* 2770 ft/min at 5000 ft, 2550 ft/min at 20,000 ft.*
Wing area: 322 sq.ft.
Weights: 11,000 lbs empty, 16,300 lbs loaded, 20,700 lbs maximum.
Armament: Six or Eight 0.50-inch machine guns with 500 rpg.
Range (clean): 800 miles at 10,000 ft._

-----------------------------------------

I still wonder how they could even hope to let us to believe the -47 would climb at 4900 ft/min ! That's an insane number for such a heavy a/c !

Anyway for the D-9 vs -47M arguement:

Lets look at the numbers...

*P-47M:*

Loaded weight: 13275 lbs.
Max. Power: 2800 hp. 

=Power loading: 4.74 lbs/hp.

*Fw-190D-9:*

Loaded weight: 9480 lbs. 
Max. Power: 2240 hp.

=Power loading: 4.23 lbs/hp

Thats very close, however the P-47 uses a wing-airfoil that is "flipped over" in shape (Kartveli-designed airfoil). The Kartveli-designed airfoil doesn't induce as much drag as a regular shape airfoil, but not as much lift either, which means an increased max speed but also a decreased climb rate. In any case the D-9's climb rate advantage over the -47M would be very small.

The Fw-190D-9's climb rate is rated at 3660 ft/min.


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## DAVIDICUS (Jun 4, 2005)

Soren, I'm not convinced that it isn't the data you have provided that is off.

I too have seen the 3,500fpm figures on various sites and believe them to be mistaken. The "D" model had an initial climb rate of 2,770fpm. The paddle bladed prop modification increased that by 400fpm to 3,200fpm. Do you really believe that the "M" model's climb performance was but 300 additional feet per minute?

From :http://home.att.net/~jbaugher1/p47_4.html

_Beginning with production blocks D-22-RE and D-23-RA, a larger (13- foot diameter) paddle-bladed propeller (either a Hamilton Standard Hydromatic 24E50-65 or a Curtiss Electric C542S) was fitted to make full use of the additional power provided by water injection. It added 400 feet per minute to the climb rate, but during landings and takeoffs there was only a scant six inches of clearance between blade tips and the ground. Takeoffs and landings must have both been hair-raising._

The figures you have provided list the "N" model literally at the "D" model's pre-paddle bladed prop figure. That can't be right. What do your sources list as the initial climb rate of the "D"? The "D" got the paddle blade in March of 1944 and it gave an impressive 400fpm increase to the initial climb rate.

The "N" model had the paddle blade. It had the "C" series engine shared by the "M" model and the XP-72. The "N" model's top speed was 467mph. The "M" model's top speed was 472mph and the XP-72's top speed was 504mph. 

The only difference between the "M" and the "D" was the "C" series engine and about 1,200 pounds of weight. If the top speed increased from 429mph on the "D" model to 472mph on the "M" model (it is reported that it actually went as fast as 488mph) , is it really conceivable that the rate of climb really only increased by 300fpm over the "D" model?

I don't think you are taking issue with the climb rate of the XP-72 which boasted a top speed of over 500mph. Given the performance of that aircraft which featured the same wings and engine as the "M" model and same engine as the "N" model, and the 3,200fpm climb rate of the paddle bladed "D" model, the 3,500fpm figure appears to be the figure that is off in my estimation.


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## evangilder (Jun 5, 2005)

Nice shots, syscom3! I heard about it from our guys. How did you hold up in the heat out there?


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## syscom3 (Jun 5, 2005)

The heat was defeated by cold beer. Works all the time.

Heres some more pix.

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## evangilder (Jun 5, 2005)

Nice! We had a few birds down there this year. Not sure which ones though because there was also formation flight training going on at Castle that same weekend.


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## mosquitoman (Jun 5, 2005)

I didn't know there were so many still flying!


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## the lancaster kicks ass (Jun 5, 2005)

that sounds like an epic battle between heat and cold beer you had there........

and MM, there's only one flying in Europe (belonging to the fighter collection, duxford), obviously there's more in america........

and that looks amazing, all those P-47s together.........


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## Nonskimmer (Jun 5, 2005)

It certainly does! I envy you, syscom.


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## cheddar cheese (Jun 5, 2005)

Wow, phenomenal shots syscom3! 8) And BTW, welcome to the site


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## DAVIDICUS (Jun 5, 2005)

I wish I had known about that airshow in Chino. I may have to travel all the way to Ohio now to see some P-47's. 

I have never seen a P-47 in flight. I have seen only one on static display.

I would love to hear one do a flyby up close.


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## the lancaster kicks ass (Jun 5, 2005)

like the new siggy CC.........


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## Soren (Jun 5, 2005)

The requested stats:

_P-47D-25-RE :
Initial climb rate: 2780 ft/min at sea-level, 1575 ft/min at 30,000ft.

P-47D-35-RA:
Max initial climb: 3120 ft/min._


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## lesofprimus (Jun 5, 2005)

Me too.....


> P-47D-25-RE :
> Initial climb rate: 2780 ft/min at sea-level, 1575 ft/min at 30,000ft.
> 
> P-47D-35-RA:
> Max initial climb: 3120 ft/min.


Whats the rate at 30K????


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## syscom3 (Jun 5, 2005)

My pleasure to post the pix for you. The Planes of Fame Museum always has a good airshow. Heres their web page. Start planning to be there next May for their 2006 airshow.
http://www.planesoffame.org/

The sound of the Jugs flying by isnt what you would expect.They make noise for sure, but its muffled. Remember that the exhaust is routed through the exhaust manifoldss into a pipe that feeds the turbocharger. Even though the turbo isnt installed anymore, the piping and ductwork is.


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## cheddar cheese (Jun 5, 2005)

Nice site! I like the Virtual tour. I see theyhave a Ba-349 and an Me-163 there. Thats on my list of places to go for sure 8)


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## Erich (Jun 5, 2005)

will agree the Chino air Museum is a hoot. filthy dirty and almost in the middle of cow poop yards (recommend nose clips in the summer....)but still worth going when they have warbirds on parade and veterans gatherings.


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## lesofprimus (Jun 5, 2005)

Ive been to Chino before as well, and I was there during the summer, and I STRONGLY recommend taking up erichs advice.....


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## syscom3 (Jun 5, 2005)

The smell isnt so bad anymore. Lots of development going up in the old cow pastures.

By the way, the people with the best view of the airshow have to be the inmates in the state prison across the street from the airport. They are directly under the main runway! 

If people want, I can post more pictures of the airshow.


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## Erich (Jun 5, 2005)

do it please. I only hae some 5x7's and 8x10's of the Recon 262 they brought out some years ago in October with friend hans Busch present, were you there for that great tribute ?


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## evangilder (Jun 5, 2005)

You also have the Yanks air museum down there. 

http://www.yanksair.com/


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## lesofprimus (Jun 5, 2005)

Has anyone ever been to Osh Kosh recently??? I went when I was 15 with my Dad and Grandpa, and ill remember it till the day i die.....


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## FLYBOYJ (Jun 5, 2005)

I used to fly into Chino all thi time, always had some great stuff around there. If the weather was good 2 or 3 of us would fly over and walk the ramp, the museum folks always had something going on.


I'm hoping next summer to fly to Oshkosh and camp out.


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## syscom3 (Jun 5, 2005)

Ok, here are two more. Two of the P47's in flight, and another (teaser) for you of a pair of Zero's taking off while a TBF and Wildcat warm up.

I think the P47's in the "vee" formation look nasty enough to scare the daylights out of the German troops!!!


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## evangilder (Jun 5, 2005)

Gotta love the bomb they put on our Zero! I am still not sure why they did that. 

You've got some nice shots syscom3! What camera gear are you using?


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## syscom3 (Jun 5, 2005)

I like this one..... a WW2 transport, the American flag, and a painting of a 1/2 naked asian babe..... hahahahhahahaha. 

What more can you ask for (besides a cold beer)?

This was from the 2004 Chino show.

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## evangilder (Jun 6, 2005)

I know that one well! That is part of our outfit, she is our flagship.


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## the lancaster kicks ass (Jun 6, 2005)

them's some amazing pics you've got yourself there.........


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## Soren (Jun 6, 2005)

lesofprimus said:


> Whats the rate at 30K????



You want to know the rate at 30K ?


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## lesofprimus (Jun 6, 2005)

Soren Quote: 

P-47D-25-RE : 
Initial climb rate: 2780 ft/min at sea-level, 1575 ft/min at 30,000ft. 

P-47D-35-RA: 
Max initial climb: 3120 ft/min. 



> You want to know the rate at 30K ?


Well why the hell post a statistic that shows 2 climb rates, and the second one only shows one.... EIther u forgot it or ur left it out on purpose... Why bother showing the comparison of the 25-RE if u cant compare the data???


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## Soren (Jun 6, 2005)

lesofprimus said:


> Soren Quote:
> 
> P-47D-25-RE :
> Initial climb rate: 2780 ft/min at sea-level, 1575 ft/min at 30,000ft.
> ...



Oh, you ment the 30,000ft performance for the D-35-RA... 

Well it only shows the max initial climb rate for that one(3120 ft/min), and unfortunately no alt is given. However as one can see, it is close to 400fpm more than the max climb rate of the D-25-RE.

Btw; why would I leave it out on purpose ? That would just be plain stupid !


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## lesofprimus (Jun 6, 2005)

Maybe some *incriminating* evidence not wanting to divulge??? Who knows. Im still not 100% with u yet, so.....

Im kinda surprised at u actually, cause ur statistical info is usually complete and precise, and this one wasnt, hence all the ????'s surrounding it...


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## syscom3 (Jun 6, 2005)

I have one pix of the P47 in the 2004 show, plus as a bonus for you Brits, a hurricane.

I have more pix to share, but i suppose i will need to open a whole new topic.

BTW, my 2 cents worth..... the P47 would defeat the FW190 everytime if it had room to dive. And the solid construction of the plane would mean the Fw190 pilot would have to make every shot count as he wouldnt have it in his sights for long.

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## Soren (Jun 6, 2005)

lesofprimus said:


> Maybe some *incriminating* evidence not wanting to divulge???



Primus, I gave the "max" climb rate numbers, so why would I leave out any alt stats ? That would be meaningless...



> Who knows. Im still not 100% with u yet, so.....



Oh, I see.. And why is that ? (Send me a PM if you want)



> I'm kinda surprised at u actually, cause ur statistical info is usually complete and precise, and this one wasn't, hence all the ????'s surrounding it...



Your "?????'s"  I haven't really seen any others


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## DAVIDICUS (Jun 6, 2005)

Soren, you wrote, " _I still wonder how they could even hope to let us to believe the -47 would climb at 4900 ft/min ! That's an insane number for such a heavy a/c ! _"

I submitted the 504mph XP-47J's climb rate as 4,900fpm. I have no reason to believe that it could not deliver on that number. I did not asert the "M" model's climb rate as 4,900fpm. I do suspect that it was probably close to 4,000fpm though. (A frankly speculative guess)

With respect to the numbers you quoted from your source, I'm still interested in knowing:

Why it would be reasonbable to accept the "N" model's initial climb rate as equal to the *pre-paddle blade* "D" model level.

AND

Why it would be reasonable to accept the "M" model's climb rate as only a few hundred fpm higher than the post paddle bladed "D" model when the top speed rocketed from 429mph for the "D" to over 470 mph for the "M". 

Keep in mind that the 500mph XP-47J 's climb rate in combat configuration was 1,700fpm higher than the post paddle bladed "D" model.

Concerning the XP-47J
From: http://home.att.net/~jbaugher1/p47_9.html

_Weights were 9663 pounds empty, 12,400 pounds normal loaded, 16,780 pounds maximum._


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## Soren (Jun 6, 2005)

syscom3 said:


> I
> 
> BTW, my 2 cents worth..... *the P47 would defeat the FW190 everytime if it had room to dive.* And the solid construction of the plane would mean the Fw190 pilot would have to make every shot count as he wouldnt have it in his sights for long.



No, it would "escape" almost everytime it had room to dive. There's a difference  

The P-47's only advantage over the Fw-190 was its diving characteristics, nothing else. (Except later -47's were faster ofcourse)


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## Soren (Jun 6, 2005)

DAVIDICUS said:


> Soren, I'm still interested in knowing:
> 
> Why it would be reasonbable to accept the "N" model's initial climb rate as equal to the *pre-paddle blade* "D" model level.
> 
> ...



Various factors can have effects on climb rate DAVID, things such as; Wing-loading, power-loading, wing-area, wing-aspect ratio, airfoil shape and so on. (Power-loading being a very decisive one)

You must agree that an a/c with a power-loading of *4.74lbs/hp*, isn't going to skyrocket at 4900ft/min ! Not even the 109 K-4 will do that !

In any case, I must agree with you DAVID, something is fishy about 'both' our data's, and this probably wont be solved before we get our hands on some reliable test-documents stating the true numbers.


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## lesofprimus (Jun 6, 2005)

> Your "?????'s"


Yes mine...

Whats the MAX rate for the 25-RE then??? That way I can compare it to the 35-RA....

See................... THATS MY POINT........ I cant use the stats u gave me.... 


> Quote:
> Who knows. Im still not 100% with u yet, so.....
> 
> 
> Oh, I see.. And why is that ? (Send me a PM if you want)


Ummm... Uve forgotten already???



> lesofprimus wrote:
> Maybe some *incriminating* evidence not wanting to divulge???
> 
> 
> Primus, I gave the "max" climb rate numbers, so why would I leave out any alt stats ? That would be meaningless...


Dude, Comeon.. Dont u have any humorous bones in ur body? IT WAS A JOKE......... Dammit, Uve been here long enough to get my humor by now.....


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## Soren (Jun 6, 2005)

lesofprimus said:


> Whats the MAX rate for the 25-RE then??? That way I can compare it to the 35-RA....
> 
> See................... THATS MY POINT........ I cant use the stats u gave me....



Oh, but you can  

We were talking max initial climb rate, and I provided for both. (Without the alt though)



> Ummm... Uve forgotten already???



I actually yes I "had", but as I've said ealier on, I hold no grudge over silly arguements. 



> Dude, Comeon.. Dont u have any humorous bones in ur body? IT WAS A JOKE......... Dammit, Uve been here long enough to get my humor by now.....



Guess not


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## lesofprimus (Jun 6, 2005)

> We were talking max initial climb rate, and I provided for both.


K, u just failed to put that max in front of the initial....


> I actually yes I "had", but as I've said ealier on, I hold no grudge over silly arguements.


K... Just making sure.........


> Guess not


I got a few Metatarsils I could share with u, or some bone chips from my elbow I'll give u free of charge...


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## Soren (Jun 6, 2005)




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## DAVIDICUS (Jun 6, 2005)

Soren, the 4,900fpm figure that I threw out was for the 504mph, 46,000ft service ceiling XP-47J. I never claimed that this figure applied to the "M" model. The issue of the 4.74 lbs/hp wing loading figure applying to 4,900fpm is a creature of your generation. 

If you look back on my earlier post, you will see that the "M" figures I gave were quoted from http://www.geocities.com/pentagon/quarters/9485/P-47M.html as follows:

_Climb, at max. gross weight (including three 75 gallon drop tanks): 4.9 minutes to 15,000 feet at 2,600 rpm (1700 hp). Reportedly, the "M" could reach 20,000 feet in 5.7 minutes at military power (2,100 hp @ 2,800 rpm). 20,000 feet in 4.75 minutes in WEP (2,800 hp @ 2,800 rpm). This is with full internal fuel and ammo. No external stores or drop tanks. In other words, normal load, clean configuration._

I don't think the above quoted figures would strike anyone as biased or otherwise incorrect. The entire purpose of quoting the "M" figures was in order to "speculate" on what the "N" model's climb rate would have been. (since no reasonable data appears to be available - further evidenced by the "N" model climb figure you quoted being at the pre-paddle blade "D" model level) As I pointed out earlier, the "M" model shared the same souped up powerplane but was lighter. In addition, however, the wing of the "N" model was larger and I'm not sure how that would have affected the climb. 

If you accept the above quoted "M" model figure, what would you estimate or guesstimate the "N" model's climb as?

Anyone?


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## Soren (Jun 6, 2005)

> Soren, the 4,900fpm figure that I threw out was for the 504mph, 46,000ft service ceiling XP-47J. I never claimed that this figure applied to the "M" model. The issue of the 4.74 lbs/hp wing loading figure applying to 4,900fpm is a creature of your generation.



Sry, a mistake on my part. I obviously thought we were talking the -47M.

However my opinion seems to be the same about the XP-47J, as its power-loading isn't much better= 4.42 lbs/hp.



> If you look back on my earlier post, you will see that the "M" figures I gave were quoted from http://www.geocities.com/pentagon/quarters/9485/P-47M.html as follows:
> 
> _Climb, at max. gross weight (including three 75 gallon drop tanks): 4.9 minutes to 15,000 feet at 2,600 rpm (1700 hp). Reportedly, the "M" could reach 20,000 feet in 5.7 minutes at military power (2,100 hp @ 2,800 rpm). 20,000 feet in 4.75 minutes in WEP (2,800 hp @ 2,800 rpm). This is with full internal fuel and ammo. No external stores or drop tanks. In other words, normal load, clean configuration._



20,000 feet in 4.75 min ! 

Seriously DAVID, that's faster than a Spit XIV.... 

I think we can rule that out as a possibility, now can't we ?


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## plan_D (Jun 6, 2005)

Spitfire XIV was 4.9 minutes to 20,000 feet, right?


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## DAVIDICUS (Jun 6, 2005)

From: http://www.spitfireperformance.com/spit14pt.html


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## Soren (Jun 6, 2005)

plan_D said:


> Spitfire XIV was 4.9 minutes to 20,000 feet, right?



A prototype made that time, yes. But it seems the production model did it in 5.1 min.

I normally go for the 4.9min figure though, as it seems more reasonable.


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## DAVIDICUS (Jun 6, 2005)

Concerning the "M" model, that 4.75 minutes to 20K figure is at WEP.

At MP, it took 5.75 minutes to reach 20K ft.


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## plan_D (Jun 6, 2005)

That's a great chart. The Meteor III had an awful climb rate, I thought it'd be better than that. 

I saw 9 minutes for Spitfire XIV climb to 20,000 feet once. I couldn't stop laughing for, oh, about 9 minutes.


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## DAVIDICUS (Jun 6, 2005)

And I once saw Soren quote 2,770 fpm as the initial climb rate for the P-47N. ( just poking fun Soren)


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## Soren (Jun 6, 2005)

DAVIDICUS said:


> Concerning the "M" model, that 4.75 minutes to 20K figure is at WEP.
> 
> At MP, it took 5.75 minutes to reach 20K ft.



The Spit's presented climb rate is with boost aswell.


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## Soren (Jun 6, 2005)

DAVIDICUS said:


> And I once saw Soren quote 2,770 fpm as the initial climb rate for the P-47N. ( just poking fun Soren)



You hurt my feelings


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## plan_D (Jun 6, 2005)

I've probably missed it but what is the initial climb rate for the P-47N? On this, what books would be good to get on the P-47?


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## Soren (Jun 6, 2005)

plan_D said:


> I've probably missed it but what is the initial climb rate for the P-47N? On this, what books would be good to get on the P-47?



"*Republic P-47 Thunderbolt*" by Frederick Johnsen, and "*Republic's P-47 Thunderbolt: From Seversky to Victory*" by Warren M. Bodie, are both good books.


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## DAVIDICUS (Jun 6, 2005)

That, my good man, is precisely what all the speculation is about. That is why the "D", "M" and XP-47J models' performance figures are being discussed. We don't seem to have any reliable "N" model climb data and are trying to extrapolate through guesstimation.

If you go back through the thread, it will all become clear ... or not.


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## plan_D (Jun 6, 2005)

5,500 feet per minute for the Hornet, that's quite impressive. Not nearly as impressive as 50,000 feet per minute which the F.6 Lightning's initial climb rate was! Amazing, since the Lightning was a 1947 design.


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## plan_D (Jun 6, 2005)

That's what I thought, Davidicus. So, I take it the Fw-190D-9 and P-47N must be pretty close in climb rates.


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## FLYBOYJ (Jun 6, 2005)

plan_D said:


> Not nearly as impressive as 50,000 feet per minute which the F.6 Lightning's initial climb rate was!



But a Bearcat is faster in a climb off the mark........

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## plan_D (Jun 6, 2005)

The Lightning will still get to 10,000 feet quicker. AVPIN kicks in, ignites the engines, brakes off and he's a rocket soaring vertically in a matter of seconds. 

My dad used to scramble 'em while with 11 Sqd....he said from scramble call to take off, under 2 minutes was easy.


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## DAVIDICUS (Jun 6, 2005)

If you accept the "M" model's climb figures that I presented (again, that's "if"), the P-47"M" pulled an average of 4,200fpm throughour its 20,000 ft climb at War Emergency Power. I would imagine that it's initial climb rate would have been 4,500fpm which would be 400fpm shy of climb rate for the super hot 504mph, 46,000 ft ceiling XP-47J.

The XP-47J had the same powerplant, same wing, but had a close fitting cowling and weighed about 1,000 lbs less in loaded configuration than the "M".

The "N" model weighed about 3,000lbs more in loaded configuration than the "M" model, had the same powerplant as the "M" and XP-47J models and had 14sq. ft. more wing area with clipped wing tips.

Yeah, I think your statement that, "_So, I take it the Fw-190D-9 and P-47N must be pretty close in climb rates._" is quite plausible if not likely. I have read that the P-47N had no problem handling the late war Japanese rice rockets like the Ki-84 Frank which had a 3,600fpm initial climb rate.


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## Soren (Jun 6, 2005)

I would guess the -47N's climb rate to be around 3,100 ft/min, and the -47M's to be the mentioned 3,500ft/min. The -47J's climb rate I would guess to be around 3,900ft/min.

The Fw-190D-9's climb rate was 3,660ft/min.


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## DAVIDICUS (Jun 6, 2005)

Clearly we are not going to resolve this issue. (At least not tonight)

The first and most obvious problem I see with the 3,100fpm initial climb rate for the P-47N is that is is below the widely accepted post paddle blade "D" model climb rate figure which you have cited.

The new "C" series engine shared by both the "M" and "N", managed to advance the top speed of the "M" model to over 470mph (It is claimed that it could actually go 488mph with some tweaking in the field) from the 429mph of the "D" model. The only other difference between the "D" and "M" was 1,200lbs of weight. The point here is that the new "C" series engine was a tremendous boost in power and performance. That same "C" series engine that drove the "M" to over 470mph drove the "N" to 467mph.

That being the case, I'm just finding it difficult to accept a lower climb rate for the "N" model vis a vis the "D" model.


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## syscom3 (Jun 7, 2005)

OK, both planes are at 30,000 ft. How much fuel is left in both aircraft and how many minutes of flying remains?

If you dont have much fuel left to fight with, you might as well as stay on the ground.


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## DAVIDICUS (Jun 7, 2005)

At 32,000 ft, I have read that the D-9 could only muster 397 mph. The "N" model P-47 could do 467 mph. 

Even the "D" model though could do 429mph at that altitude.


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## dinos7 (Jun 7, 2005)

fw 190


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## Soren (Jun 7, 2005)

DAVIDICUS said:


> The first and most obvious problem I see with the 3,100fpm initial climb rate for the P-47N is that is is below the widely accepted post paddle blade "D" model climb rate figure which you have cited.



It could be 3,150ft/min, that's a tiny bit more, I just said it would probably be 'around' the 3,100ft/min.

You must remember the -47N weighs about 2,000lbs more than the -47D, that's why I figure its climb rate was about equal or at most a tiny bit better than the -47D's.


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## Soren (Jun 7, 2005)

DAVIDICUS said:


> At 32,000 ft, I have read that the D-9 could only muster 397 mph. The "N" model P-47 could do 467 mph.
> 
> Even the "D" model though could do 429mph at that altitude.



The -47's straight out speed is highly thanks to its low drag wing-design.

But yes, at high alt the -47 is superior to the D-9 in all but maneuverability.


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## FLYBOYJ (Jun 7, 2005)

syscom3 said:


> OK, both planes are at 30,000 ft. How much fuel is left in both aircraft and how many minutes of flying remains?
> 
> If you dont have much fuel left to fight with, you might as well as stay on the ground.



9 or 10 minutes to 30,000 - fuel burn, say about 50-75 GPH full power average both planes, P-47 carries over 300 gallons, -190 D9, 138 gallons, do the math, there's plenty of fuel left!


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## DAVIDICUS (Jun 7, 2005)

The P-47M had the same wing as the P-47D. The only difference was that the "M" weighed 1,200lbs less and had the "C" series engine. Those two factors increased the top speed from 429 to over 470 miles per hour.

The "N" weighed about 2,000lbs more than the "D" but was still able to muster 467 miles per hour.

One thing we can all agree on is that the 2,800hp "C" series engine was a powerful performance enhancer.


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## Soren (Jun 7, 2005)

DAVIDICUS said:


> One thing we can all agree on is that the 2,800hp "C" series engine was a powerful performance enhancer.



Certainly.


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## Jank (Jun 7, 2005)

According to those tests with the captured 190, the P-47 would also out manuever a Fock Wulf at very low altitudes as well.


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## Soren (Jun 7, 2005)

Jank said:


> According to those tests with the captured 190, the P-47 would also out manuever a Fock Wulf at very low altitudes as well.



That was a Fw-190"A", with a not properly working engine.


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## DAVIDICUS (Jun 7, 2005)

Yes it was an "A" model. But for that matter, the the P-47 was a Razorback D-4 with the toothpick propeller.

The excerpt that people appear to sieze upon in asserting that the engine was not working properly is the following:

_The engine seems to run rough at all times and the vibration transmitted through the control column almost completely destroys any feel of the flying characteristics._

But let's also not forget this other gem of an excerpt:

_ The FW-190 was in exceptionally good condition for a captured airplane, and developed 42 inches on take-off which is believed to be slightly above normal maximum boost_ 

The fact that the engine "seemed" to run rough and vibrated may have been in part a reflection of the FW-190's engine's natural state of operation rather than an indication that the engine was not operating correctly. Radials were not as smooth as in-lines and the German radials were known to run rougher than the American radials.


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## DAVIDICUS (Jun 7, 2005)

Soren said:


> DAVIDICUS said:
> 
> 
> > Concerning the "M" model, that 4.75 minutes to 20K figure is at WEP.
> ...



Yes, 18lbs of boost. There was more boost available as I have seen 25lbs of boost on data before.


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## syscom3 (Jun 7, 2005)

FLYBOYJ said:


> syscom3 said:
> 
> 
> > OK, both planes are at 30,000 ft. How much fuel is left in both aircraft and how many minutes of flying remains?
> ...



OK.. so the P47 can enter combat with more fuel and can simply fly above the FW and wait untill the FW runs low on fuel and then pounce on it. If the FW manages to elude the P47, then the P47 dives away and zooms for altitude for another try.


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## FLYBOYJ (Jun 7, 2005)

syscom3 said:


> FLYBOYJ said:
> 
> 
> > syscom3 said:
> ...



Now think about this - that P-47 already flew a few hundred miles to get over Germany, and still has to fly home. I know there's been performancce charts shown here, you could probably calcualte how long each aircraft could stay and fight.


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## Sal Monella (Jun 8, 2005)

On the issue of the P-47-N's climb rate, I recall reading that in tests against the Hellcat, the P-47 showed a higher climb rate. The Hellcat's climb rate was 3,240 fpm.


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## evangilder (Jun 8, 2005)

I also show the Hellcat climb rate at 3,240 fpm. That is according to Encyclopedia of the World'd Combat Aircraft by Bill Gunston. According to that same book, the climb rate of a P-47 (typical) was 2,800 fpm. the weights and sizes of these airplanes are fairly similar as well.


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## DAVIDICUS (Jun 8, 2005)

The "tyical" P-47 was the toothpick propeller model that is usually referenced at 2,770 or 2,780 fpm (2,800 appears to be a rounded figure). The paddle blade on the "D" added another 400 fpm on to that.

I haven't read about tests between the "N" model and the Hellcat but it does seem reasonable that they would have been conducted as the petformance of the Hellcat against a variety of enemy fighters was well known. Thus, it seems that it would have been a valuable exercise to test the P-47N against the Hellcat since they would be facing the same opponents.


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## evangilder (Jun 8, 2005)

The book did not specify which type, and I do know the paddle blade do make a difference. I haven't seen the numbers documented, but the number you quote seem reasonable.

Perhaps they did not test the -47N and the Hellcat against one another as they are fairly equal in size, weight and performance. They were probably more focused on getting the planes out to the theater to put an end to thing, I would guess.


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## DAVIDICUS (Jun 8, 2005)

The "N" model was considerably heavier and had a much more powerful powerplant. As to performance, much of this thread is speculation and debate about the climb rate of the "N." It is clear though that the P-47N was about 90 miles per hour faster than the Hellcat and its engine could retain more horsepower way up high due to the turbosupercharger.


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## Soren (Jun 8, 2005)

> Yes it was an "A" model. But for that matter, the the P-47 was a Razorback D-4 with the toothpick propeller.



Sure, but the D-4 was afterall lighter.



> The excerpt that people appear to sieze upon in asserting that the engine was not working properly is the following:
> 
> _The engine seems to run rough at all times and the vibration transmitted through the control column almost completely destroys any feel of the flying characteristics._



And here's why that excerpt is so important:

The Fw-190 has been explained by its pilots as a dream to fly, with no vibrations and excellent controls with very good feel to them. so thats why that excerpt is so important.



> But let's also not forget this other gem of an excerpt:
> 
> _ The FW-190 was in exceptionally good condition for a captured airplane, and developed 42 inches on take-off which is believed to be slightly above normal maximum boost_



In exceptional good condition for a *captured* a/c  Something was wrong with it..



> The fact that the engine "seemed" to run rough and vibrated may have been in part a reflection of the FW-190's engine's natural state of operation rather than an indication that the engine was not operating correctly.



The BMW-801 ran very smoothly DAVID, as described by its pilots, and the 190's controls had excellent feel.



> Radials were not as smooth as in-lines



True, however that does not at all mean you can't make it run smooth.



> and the German radials were known to run rougher than the American radials.



 

Who ever told you that ?


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## Soren (Jun 8, 2005)

DAVIDICUS said:


> Yes, 18lbs of boost. There was more boost available as I have seen 25lbs of boost on data before.



Sure, but thats for the 5.1min time, with 25lbs of boost it could probably make it in 4.9min. So nothing has changed.


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## DAVIDICUS (Jun 8, 2005)

Yes the D-4 was lighter ... than a destroyer.  

You left out the "_... and developed 42 inches on take-off which is believed to be slightly above normal maximum boost._" from your critique of that excerpt.

I have never read about Fw-190 pilots reporting "no vibration" or that the controls had an excellent feel. I defer to you.

I have read that the German radials ran rough. I don't recall where I read it and am not going to vouch for its accuracy. Again, I defer to you.

I do not see the Mk. XIV climb data as fatal to the WEP P-47M data I presented.

If you look at the chart I presented for the climb of the Mk. XIV at 18lbs of boost, you will note that the initial climb rate is 4,700fpm! Obviously at 25lbs of boost, the initial climb rate would be even higher. The initial climb figure I estimated from the 4.75 minutes to 20K feet for the P-47M at WEP was about 4,500fpm based on the average of 4,200fpm over the entire climb.

You earlier claimed that the WEP P-47M data I presented indicated a higher climb rate than the Mk. XIV. You said, "_Seriously DAVID, that's faster than a Spit XIV...._" Obviously this isn't so.


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## Soren (Jun 8, 2005)

> Yes the D-4 was lighter ... than a destroyer.



It was lighter than most other -47's. 



> I do not see the Mk. XIV climb data as fatal to the WEP P-47M data I presented.
> 
> If you look at the chart I presented for the climb of the Mk. XIV at 18lbs of boost, you will note that the initial climb rate is 4,700fpm! Obviously at 25lbs of boost, the initial climb rate would be even higher. The initial climb figure I estimated from the 4.75 minutes to 20K feet for the P-47M at WEP was about 4,500fpm based on the average of 4,200fpm over the entire climb.



With 25lbs of boost, the Spit XIV's max initial climb rate was 5,040ft/min, and it would according to tests reach 20,000ft in 4.9min with this amount. 



> You earlier claimed that the WEP P-47M data I presented indicated a higher climb rate than the Mk. XIV. You said, "_Seriously DAVID, that's faster than a Spit XIV...._" Obviously this isn't so.



Whoops, there you seriously stumbled DAVID !  

I wasn't talking the initial climb rate, but the time to 20,000ft.  

The -47M is quoted as reaching 20,000ft in 4.75min, which is just not true ! The Spit XIV would reach 20,000ft in 5.1min, or 4.9min at best.

And clearly in reality the -47M wont be climbing faster than the Spit XIV ! It wont even be close.


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## DAVIDICUS (Jun 8, 2005)

First off, I find it hard to believe that the time would go from 5.1 to 4.9 when the boost goes from 18lbs to 25lbs.

As to my "serious stumble," this entire discussion has always been about the initial climb rate for the P-47N. The "M" and "J" figures were employed only to discern and estimate the intial climb rates. 

I have only listed time to altitude figures (because that's all I have to work with) in order to estimate the initial climb rate. Can you find anywhere where I have argued time to altitude figures except in response to your claims?

Lastly, I promise not to inject a smiley face at your "serious stumble" in citing my quoted WEP P-47"M" 0-20K flight time as 4.15minutes. It was 4.75 minutes Soren. As the altitude increased, the P-47"M" didn't suffer from as much loss of horsepower as the Mk. XIV due to the turbosupercharger. Remember that the P-47 was literally designed around the turbosupercharger to give it high altitude superiority.


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## DAVIDICUS (Jun 8, 2005)

I see you have corrected your stumble.


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## Soren (Jun 8, 2005)

> First off, I find it hard to believe that the time would go from 5.1 to 4.9 when the boost goes from 18lbs to 25lbs.



Why ? 



> As to my "serious stumble," this entire discussion has always been about the initial climb rate for the P-47N. The "M" and "J" figures were employed only to discern and estimate the intial climb rates.



Your "Serius stumble" was that you left out what I was actually saying, in effect you were putting words into my mouth.

Here's what I said:_ 20,000 feet in 4.75 min ! 

Seriously DAVID, that's faster than a Spit XIV.... _



> Lastly, I promise not to inject a smiley face at your "serious stumble" in citing my quoted WEP P-47"M" 0-20K flight time as 4.15minutes. It was 4.75 minutes Soren.



DAVID dont take offense that easely, I put that smiley there to indicate "NO offense is to be taken"



> As the altitude increased, the P-47"M" didn't suffer from as much loss of horsepower as the Mk. XIV due to the turbosupercharger. Remember that the P-47 was literally designed around the turbosupercharger to give it high altitude superiority.



DAVID that difference only really kicked in at 30,000ft, the Spit enjoyed a huge power-loading and wing-loading advantage all the way up to 20,000ft . Nontheless all the numbers are against the -47 making that time, even with full boost all the way.


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## DAVIDICUS (Jun 8, 2005)

Actually the emoticon you used after saying, "_Whoops, there you seriously stumbled DAVID !_" is called "Very Happy."

At any rate, misunderstandings aside and back to the topic at hand, the the "M" model's initial climb rate under the cited WEP figure would not exceed the Mk. XIV's under even 18lbs of boost let alone 25lbs of boost. I am only interested in initial climb rates for ther purpose of estimating the initial climb rate for the P-47N.

Oh, and the turbosupercharger on the P-47 did not initially kick in, or otherwise become effective, starting at at 30K. For example, at 25,000ft when other aircraft's engines were feeling the strain of the thin air, the P-47 was not similarly strained because it's turbosupercharger was not yet operating and making a difference.

Lastly, as you well know, there is more to the picture than simply wing area/weight and horsepower. Propeller efficiency plays a big role too as evidenced by the additional *400fpm* of climb that the paddle blade propeller afforded the "D" model under conditions where the wing area/weight and horsepower of the "D" remained the same.


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## Soren (Jun 8, 2005)

> Actually the emoticon you used after saying, "_Whoops, there you seriously stumbled DAVID !_" is called "Very Happy."



You read the emotions description rather than looking at it ? It was ment to represent a reassuring smiling face, which it did. I wanted to make it clear that I wasn't after you in any way.

Btw where is the reassuring smiley after you said I stumbled ? Thats not fair, I want one too !!    (Ok I'll stop now  )



> I am not prepared to verify your assertion of the 4.9 and 5.1 minutes to 20K ft. altitude.



You don't have to, I'll just give it to you instead: http://www.spitfireperformance.com/jf319.html



> I am only interested in initial climb rates for ther purspose of estimating the initial climb rate for the P-47N.



Ok.



> Oh, and the turbosupercharger on the P-47 did not initially kick in, or otherwise become effective starting at, at 30K. For example, at 25,000ft when other aircraft's engines were feeling the strain of the thin air, the P-47 was not similarly strained because it's turbosupercharger was not yet operating and making a difference.



I didnt mean the Turbocharger would initially kick in, I meant the difference would only initially begin to kick in at around 30,000ft.


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## DAVIDICUS (Jun 8, 2005)

_"I didnt mean the Turbocharger would initially kick in, I meant the difference would only initially begin to kick in at around 30,000ft._"

I said , " ... or otherwise become effective starting at 30K." I followed that up with the example that at 25K feet it was making a difference.

I just took a look at your data on the Mk. XIV. The climb rate at 1,700ft was *5,110fpm* for *18.3 lbs* of boost (remember there was the potential for 25lbs of boost which represents a 38% increase over 18lbs.). 

I speculated that the maximum initial climb rate of the P-47M at War Emergency Power might be as high as 4,500fpm which is *600 fpm less * than the Mk. XIV utilizing just 18.3lbs of boost. I also speculated that the climb rate for the heavier "N" might initially be around 3,500fpm (near the rate of the Fw-190D-9).


Why don't we just throw in the towel and agree to disagree Soren.


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## Sal Monella (Jun 8, 2005)

Whatever the time to altitude figures are, I think those estimates for initial climb sound pretty reasonable David.


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## lesofprimus (Jun 8, 2005)

Great stuff, but i dont really see how this applies to the -47 vs. the -190...


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## DAVIDICUS (Jun 8, 2005)

Cheddar Cheese raised the issue of a head to head match between the FW-190D-9 and the P-47N. Because no reliable climb data appears available for the "N" model, the "M" and "J" data was referenced which gave rise to a side discussion on the reliability of the "M" data.


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## lesofprimus (Jun 8, 2005)

I followed that much... But why is the initial climb data so topically important?? Thats just a small part of what the combat would evolve into...


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## DAVIDICUS (Jun 8, 2005)

Well Les, it could have been about armament, dive speed, roll rate, (you get the idea) or any of a host of other specific attributes that end up being hashed about on this forum that individually make up only a small part of what combat involves.

So in response to your question, and a response I might add that you have probably given your kid on more than one occasion, "Just because."


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## Soren (Jun 8, 2005)

> I said , " ... or otherwise become effective starting at 30K." I followed that up with the example that at 25K feet it was making a difference.



I wasnt talking the -47 alone, but the difference between the -47 and the Spit XIV. At 25,000ft the Spit XIV still climbs noticably better.



> I just took a look at your data on the Mk. XIV. The climb rate at 1,700ft was *5,110fpm* for *18.3 lbs* of boost (remember there was the potential for 25lbs of boost which represents a 38% increase over 18lbs.).



According to this doucment on the production model the climb rate was 4650-4700ft/min with 18lbs boost, which was the max allowable boost: http://www.spitfireperformance.com/spit14climbchart.jpg

With 25lbs boost, the max initial climb rate would likely have risen to 5200ft/min. (I don't know where you get 38% increase from)

In any case, 20,000ft was reached in 5.1min during that test, and with 25lbs boost it would most likely reach this in 4.9min. 

Can we agree that the -47M would never reach 20,000ft in 4.75min ?

Even the Spit 21 couldnt reach 20,000ft in under 5.2min, or 5min at best.



> I speculated that the maximum initial climb rate of the P-47M at War Emergency Power might be as high as 4,500fpm which is *600 fpm less * than the Mk. XIV utilizing just 18.3lbs of boost.



I could go along with 4,000 ft/min for the -47M as a max, but it would slow down very quickly, much more quickly than the Spit XIV.




> I also speculated that the climb rate for the heavier "N" might initially be around 3,500fpm (near the rate of the Fw-190D-9).



I speculate the -47N's climb rate to be around 3,150ft/min, but I could go along with 3,500ft/min souly because of its sheer starting speed, however it would slow down REAL quick.



> Why don't we just throw in the towel and agree to disagree Soren.



Lets see if we can't agree to agree with the above first


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## GrayWard (Jun 8, 2005)

Did anyone read the excellent article in the winter 2005 "Flight Journal" on German fighters that discussed a comparison of a FW190A-4 against a F6F-3 and F4U-1D. They compared rate of climb, horizontal speed, horizontal acceleration, rate of role, maneuverability, stability and control, angle of vision, general characteristics in mock combat and armament.This was done in 1944 with a captured 190. It gives a good indication of how it would stand against the P47. It was thought using the right tactics the American fighters would come out on top.

Gray.


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## Soren (Jun 8, 2005)

GrayWard said:


> Did anyone read the excellent article in the winter 2005 "Flight Journal" on German fighters that discussed a comparison of a FW190A-4 against a F6F-3 and F4U-1D. They compared rate of climb, horizontal speed, horizontal acceleration, rate of role, maneuverability, stability and control, angle of vision, general characteristics in mock combat and armament.This was done in 1944 with a captured 190. It gives a good indication of how it would stand against the P47. It was thought using the right tactics the American fighters would come out on top.
> 
> Gray.



Yeah I read it. 

You can read here aswell: http://www.geocities.com/slakergmb/id88.htm


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## marseille jr (Jun 8, 2005)

for escort duties I'd mount a p47 (range, dive, armor)
for dogfights a dora (or a ta-152) would be the byrd of preference here (cannons, more nimble, climb)


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## DAVIDICUS (Jun 8, 2005)

"_According to this doucment on the production model the climb rate was 4650-4700ft/min with 18lbs boost, which was the max allowable boost_" 

Yes, well I thought you would prefer the document that *you* cited. Just as I prefer the "M" data that I cited over that which you cited. Your data states 5,110fpm at 18.3lbs of boost at 1,700ft. http://www.spitfireperformance.com/jf319.html
Are you now claiming that your data, which we have been arguing about, should not be trusted? Is there any other data or figures that you would like to withdraw at this time?


25 is 38% more than 18. An increase in boost from 18lbs to 25lbs represents an increase in boost of 38%. I still find it hard to believe that such an increase would shave only 12 seconds off the entire climb almost four miles up to 20K feet. Think about that for a second (or twelve). You yourself said that going to 25lbs from 18lbs would mean a difference of 4.9 minutes as opposed to 5.1 minutes in a climb to 20K (that's 12 seconds).  

You also said, "_With 25lbs of boost, the Spit XIV's max initial climb rate was 5,040ft/min, and it would according to tests reach 20,000ft in 4.9min with this amount_." Where did this come from? The Mk. XIV data I presented only was for 18lbs of boost and indicated an initial climb rate of 4,700fpm. Your data, on the other hand, indicated 5,110 ft/min for just 18.3lbs as opposed to 25lbs of boost. Where did you get the 5,040fpm at 25lbs of boost figure from?

Earlier you estimated the "M" model's initial climb to be 3,500fpm. Now we're at 4,000fpm. You also estimated the initial climb of the XP-47J (the 504mph, 46,000ft ceiling fighter) to be but 3,900fpm.

At high altitude, the Spitfire doesn't have the advantage of P-47's turbosupercharger. That's why the P-47 was such a hot ship at high altitude. I don't really know how the climb performance between the Mk. XIV and "M" model would compare from say 30K to 40K ft. Perhaps fuel for another discussion.

I sense you are coming around, albeit slowly. If we go around for another 16 pages of posts I'm sure I can convince you but I think we've beat this one into the ground.


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## DAVIDICUS (Jun 8, 2005)

Thanks for posting the link Soren. I haven't read it.

So it really indicated that using the right tactics the P-47 would come out on top?

Interesting. Do you agree Soren?


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## lesofprimus (Jun 8, 2005)

> So in response to your question, and a response I might add that you have probably given your kid on more than one occasion, "Just because."
> _________________


OK, Ill buy that for a Dollar...


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## Sal Monella (Jun 8, 2005)

I bet you're a good lawyer. What kind of law do you do?


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## FLYBOYJ (Jun 8, 2005)

Soren, Davidicus, got a question for both of you.....

In your discussions, you guys keep talking about "boost" assuming you mean supercharger boost measured in inches of mercury at the intake manifold, and then relating this to climb perfomance. Are you gathering this data from flight manuals? I could tell you that at a given desired "boost" or manifold pressure you also have to consider RPM which is controlled by propeller setting, not the throttle. Comments?


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## Soren (Jun 8, 2005)

> Yes, well I thought you would prefer the document that *you* cited. Just as I prefer the "M" data that I cited over that which you cited. Your data states 5,110fpm at 18.3lbs of boost at 1,700ft. http://www.spitfireperformance.com/jf319.html
> Are you now claiming that your data, which we have been arguing about, should not be trusted? Is there any other data or figures that you would like to withdraw at this time?



Lets keep this friendly shall we ? 

If you read my posts more properly you will not missunderstand them so much, here's what I said: 
_According to this doucment on the *production model* the climb rate was 4650-4700ft/min with 18lbs boost, which was the max allowable boost: http://www.spitfireperformance.com/spit14climbchart.jpg _

The 5,110fpm at 18.3lbs of boost at 1,700ft figure, is for the prototype.  




> 25 is 38% more than 18. An increase in boost from 18lbs to 25lbs represents an increase in boost of 38%. I still find it hard to believe that such an increase would shave only 12 seconds off the entire climb almost four miles up to 20K feet. Think about that for a second (or twelve). You yourself said that going to 25lbs from 18lbs would mean a difference of 4.9 minutes as opposed to 5.1 minutes in a climb to 20K (that's 12 seconds).



Which is pretty much, DAVID. The 18lbs boost only lasted *5min*  



> You also said, "_With 25lbs of boost, the Spit XIV's max initial climb rate was 5,040ft/min, and it would according to tests reach 20,000ft in 4.9min with this amount_."



I was still talking the production model.



> Earlier you estimated the "M" model's initial climb to be 3,500fpm. Now we're at 4,000fpm.



Don't put words into my mouth DAVID ! I said I speculated it to be 3,500ft/min, but I was willing go up to 4,000ft/min to satisfy you DAVID. I still think 3,500ft/min is the most reasonable number.



> You also estimated the initial climb of the XP-47J (the 504mph, 46,000ft ceiling fighter) to be but 3,900fpm.



Which it most likely was, it wasnt 4,900ft/min for sure, thats faster than a Bf-109K-4.

DAVID this whole arguement started with me objecting to your crazy 20,000ft in 4.15min/4.75min figure, but somhow we got it twisted to initial climb rate. All im 'really' concerned about is the 20,000ft time. 



> At high altitude, the Spitfire doesn't have the advantage of P-47's turbosupercharger. That's why the P-47 was such a hot ship at high altitude.



True, and I never denied that. But at 25K feet the Spit XIV still climbs faster, as its powerloading and wingloading still gives it the edge. 



> I don't really know how the climb performance between the Mk. XIV and "M" model would compare from say 30K to 40K ft. Perhaps fuel for another discussion.



At that altitude the P-47 is superior, also in the climb I would suspect.



> I sense you are coming around, albeit slowly.



Not really, Im just tired of this discussion and want it finished. But hey, lets rock !   



> If we go around for another 16 pages of posts I'm sure I can convince you but I think we've beat this one into the ground.


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## Soren (Jun 8, 2005)

DAVIDICUS said:


> Thanks for posting the link Soren. I haven't read it.



No problem.



DAVIDICUS said:


> So it really indicated that using the right tactics the P-47 would come out on top?
> 
> Interesting. Do you agree Soren?



Against the Fw-190A-4, definitely.


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## DAVIDICUS (Jun 8, 2005)

The 5,110fpm at 18.3lbs of boost at 1,700ft. on Soren's chart is at 2,750rpm. http://www.spitfireperformance.com/jf319.html 


The chart I posted earlier in the thread which indicated an initial climb of 4,700fpm at 18lbs of boost was also at 2,750rpm.
http://www.spitfireperformance.com/spit14pt.html

Soren, you mentioned an A-4 but the Fw-190 in the tests referenced above by Gray Ward and linked by you were with an A-5.


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## FLYBOYJ (Jun 8, 2005)

OK - now I'm seeing RPM posted. Without that you're missing part of the equation.


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## Soren (Jun 8, 2005)

Guy's, I won't be able to answer for a few hours, as its hard concentrating when you've got the flu  So I need to rest a little, but "I'll be back" :robot:


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## lesofprimus (Jun 8, 2005)

> DAVIDICUS wrote:
> So it really indicated that using the right tactics the P-47 would come out on top?
> Interesting. Do you agree Soren?
> 
> ...


And its also indicated, that with the right tactics, the Fw-190A-4 would come out on top....Pilots didnt always have the chance to fly with the right tactics... If u get bounced outta the Sun, tactics dont mean shit... 

Survival does...


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## DAVIDICUS (Jun 8, 2005)

"_The 5,110fpm at 18.3lbs of boost at 1,700ft figure, is for the prototype. _"

Ah, I did not see that.  

"_DAVID this whole arguement started with me objecting to your crazy 20,000ft in 4.15min/4.75min figure, but somhow we got it twisted to initial climb rate. All im 'really' concerned about is the 20,000ft time. _"

I don't know how you got twisted around. This whole thing started as a search for the initial climb rate of the "N" for comparison purposes with the Fw-190-D-9. 

There did not appear to be reliable data (you yourself posted data that indicated that the "N" had a poorer initial climb rate than the pre-paddle blade "D" model) so I threw out "M" and "J" data and started to discuss the weight differences, engine similarities and wing differences/similarities for speculative purposes. 

Twice now you have quoted me as giving a 4.15min figure as time to 20K for the "M". Again, I have never posted or even eluded to any 4.15min figure for this aircraft. The info I offered for the "M" is below:

http://www.geocities.com/pentagon/quarters/9485/P-47M.html 

Climb, at max. gross weight (including three 75 gallon drop tanks): 4.9 minutes to 15,000 feet at 2,600 rpm (1700 hp). Reportedly, the "M" could reach 20,000 feet in 5.7 minutes at military power (2,100 hp @ 2,800 rpm). 20,000 feet in 4.75 minutes in WEP (2,800 hp @ 2,800 rpm). This is with full internal fuel and ammo. No external stores or drop tanks. In other words, normal load, clean configuration. 

Soren said, "_Don't put words into my mouth DAVID ! I said I speculated it to be 3,500ft/min, but I was willing go up to 4,000ft/min *to satisfy you DAVID*._"

OK, now you're starting to sound like my wife.  

And as with some of the fights with my wife, I'm growing weary of this discussion too. 

See you on another thread and again. 

Les, those tests are with an A-5.


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## DAVIDICUS (Jun 8, 2005)

On the issue of vibration and the Fw-190A-4, I found the following.

From: http://www.vectorsite.net/avfw190.html#m2

_The "FW-190A-4" went into production in late 1942, the primary improvement being the addition of an "MW-50" water-methanol power boost system for the BMW-801 engine. The MW-50 injected water into the engine's cylinders to raise the engine's redline limit for a short period of time. The methanol was mainly intended as anti-freeze. The A-4 also introduced a small but distinctive modification in the form of a short radio aerial mast mounted on top of the tailfin. This item would be retained in later production. The A-4 was the first FW-190 subvariant to see real service on the Eastern Front.

In April 1943, the production lines began turning out the next subvariant, the "FW-190A-5", which was almost indistinguishable from the A-4 but *added a longer engine mounting to increase strength and reduce vibration*. The new mounts stretched the aircraft by about 15 centimeters (six inches) and became production standard. _

So, according to the above, the longer engine mounting was for (1) increased strength and (2) a reduction in vibration.

Apparently, in the A-4, vibration was a problem that was large enought to be a cause for modification in order to bring about its reduction.

When I wrote earlier that, "The fact that the engine "seemed" to run rough and vibrated may have been in part a reflection of the FW-190's engine's natural state of operation rather than an indication that the engine was not operating correctly. Radials were not as smooth as in-lines and the German radials were known to run rougher than the American radials." I may not have been so far off.


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## Soren (Jun 9, 2005)

DAVIDICUS said:


> Ah, I did not see that.



No problem.



> I don't know how you got twisted around. This whole thing started as a search for the initial climb rate of the "N" for comparison purposes with the Fw-190-D-9.



I'm pretty convinced I wasn't alone twisting the argument, but that doesn't matter.



DAVIDICUS said:


> Twice now you have quoted me as giving a 4.15min figure as time to 20K for the "M". Again, I have never posted or even eluded to any 4.15min figure for this aircraft. The info I offered for the "M" is below:



Man you need glasses m8....  

DAVID I repeat: If you read my posts properly you wont misunderstand them so much, here's what I said: 
_DAVID this whole arguement started with me objecting to your crazy 20,000ft in 4.15min*/4.75min* figure, but somhow we got it twisted to initial climb rate. All im 'really' concerned about is the 20,000ft time. _

I was talking about both  



DAVIDICUS said:


> OK, now you're starting to sound like my wife.



Bad choice of words on my part !  



> And as with some of the fights with my wife, I'm growing weary of this discussion too.
> 
> See you on another thread.



Aaarh come on DAVID... don't get so easily offended. Especially since you took offense to something that wasn't there  

-----------------------------------------------

Anyway, lets start on a fresh one. This time we keep it clear what were talking about, so as to avoid any more confusion.

Your reference states:

P-47M time to 20,000ft 4.75min. But no Max. Initial climb rate.

XP-47J time to 20,000ft 4.15min. And a Max initial climb rate of 4,900ft/min.

My problem with these numbers:

*P-47M:*
Its time to 20,000ft is beyond reality, here's why:

P-47M: 
Power-loading= 4.74 lbs/hp (used WEP 2800hp figure for calc.)
Wing-loading= 43.1 lbs/sq.ft.

Spit XIV:
Power-loading= 4.09 lbs/hp (Used 18lbs boost 2050hp figure for calc.)
Wing-loading= 33.8 lbs/sq.ft.

Spit XIV time to 20,000ft= 5.1min.

*XP-47J:*
Its time to 20,000ft is beyond reality aswell, here's why:

ZP-47J:
Power-loading= 4.76 lbs/hp (Used 2800hp WEP figure, weight figure from http://aeroweb.brooklyn.cuny.edu/specs/republic/xp-47j.htm )
Wing-loading= 44.5lbs/sq.ft. (Used wing and weight figure from http://aeroweb.brooklyn.cuny.edu/specs/republic/xp-47j.htm )
Compare the this to the Spit XIV's data---

*Next XP-47J issue:*
Its initial climb figure is ridiculous, here's why:

Bf-109K-4:
Power-Loading= 3.41lbs/hp.
Wing-loading= 38.7 lbs/sq.ft.

K-4 Initial climb rate: 4,823ft/min (1,470m/min)

XP-47J:
Power-loading= 4.76 lbs/hp (Used 2800hp WEP figure, weight figure from http://aeroweb.brooklyn.cuny.edu/specs/republic/xp-47j.htm )
Wing-loading= 44.5lbs/sq.ft. (Used wing and weight figure from http://aeroweb.brooklyn.cuny.edu/specs/republic/xp-47j.htm )

XP-47J Initial climb rate: 4,900ft/min

*The XP-47J's time to 30,000ft is beyond reality aswell:*
Bf-109K-4 time to 30K feet= 6.7min
XP-47J time to 30K feet= 6min 45 sec


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## Soren (Jun 9, 2005)

DAVIDICUS said:


> On the issue of vibration and the Fw-190A-4, I found the following.
> 
> From: http://www.vectorsite.net/avfw190.html#m2
> 
> ...



You werent far off DAVID, as radials always vibrate more than in-line engines. However AFAIK there are no facts supporting that american radials ran smoother than German radials.

What I know from pilot accounts, is that the Fw-190 was praised for its excellent controls with good feel, and that no vibration has ever been mentioned as a problem. But maybe that only applied for the A-5 and onwards, and not the A-4. (It 'is' a possibility)

I am however convinced that the A-4 did not have any excessive vibrations that in any way destroyed the feel of the controls, as it has never been mentioned by any Fw-190 pilot.


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## DAVIDICUS (Jun 9, 2005)

"_ This time we keep it clear what were talking about, so as to avoid any more confusion._"

Since you want to keep clear what we're talking about, it's the initial climb rate of the P-47N. Alll the "M" and "J" data that we tossed about was for purposes of comparison and extrapolation.

Let's start out fresh. What do you think the initial climb rate of the "N" is? 

P-47N
Weight is 16,300lbs normal load

Wing area is 322sq. ft. / Wing loading is 50.62

Engine is 2,800hp / Power loading is 5.82

Top speed 467mph

Initial climb rate - Unknown.

P-47D
Weight is 14,600lbs normal load

Wing area is 300 sq. ft. / Wing loading is 48.67

Engine is 2,300hp. / Power loading is 6.35

Top speed 429mph

Initial climb rate - 3,180fpm.

We can start with the "D" as I gather from the thread that unlike with the "M" and "J", there is no disagreement that the pre-paddle blade initial climb rate was 2780fpm and the post paddle blade climb rate was 400fpm more or 3,180fpm. 

So, given the above figures for the "D", what do you think the "N" could pull in initial climb rate? I agree with Plan_D's suggestion that it would be close to the Fw-190 D-9 which you mentioned was 3,660fpm. (I'm actually thinking 3,500fpm.)

You said that the "N" model's initial climb rate might be as high as 3,150fpm.

The issue of wing loading and power loading, while helpful, doesn't present a necessarily accurate template in which to analyze this issue. For instance, merely changing the propeller on the "D" model yielded a 400fpm increase in climb rate with no change in horsepower, weight or wing area. If prior to the paddle blade's introduction, someone were to ask you to calculate what the increase in climb rate would be for the paddle blade model using horsepower, weight and wing area, you would be exactly 400fpm off.

If at all possible, I think it is helpful to use similar versions of the same aircraft because the significance of important variables like propeller efficiency, aerodynamics, wing design as it relates to lift/drag etc. are mitigated. I would prefer to use other P-47's as opposed to Spitfires or Me-109's which are really entirely different creatures.

We know that the "N" model had the same propeller as the post paddle blade 'D" model. We know that the "C" series engine of the "N" developed 500 more horsepower, and we know that the wing area of the "N" increased by 22sq.ft. Lastly, we know that the "N" had a normal loaded weight that was 1,700lbs more.

Using the post paddle blade "D" as a baseline then, what effect do you think that the interplay between the heavier weight, greater wing area and more powerful engine would have had?

I think the "M" data (whatever that may be) is helpful except that we can't agree on what it is. It had a similar top speed with the same powerplant but was significantly lighter. It also shared the "D" model's wing. 

The "J" data (also in contention) was thrown in by me to lend credence to the "M" data.

Why don't we just start with the "D" data that isn't in contention and discuss where that takes us?

If we must examine different aircraft, I propose that we then examine the F6F Hellcat and F4U Corsair for their more similar size/shape and weight before resorting to the very different Spitfires and Me-109's.

I think that's reasonable don't you?


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## DerAdlerIstGelandet (Jun 9, 2005)

It would depend on what I was using the aircraft for. For escort duties I would go with the P-47 however all other ways I would go with a Fw-190A-8 or a Fw-190D-9. 

Not to knock the P-47. She was a marvelous aircraft and to me one of the most underated allied aircraft (she is often overshadowed by the less capable P-51), but I think the later Fw-190's were a more superior aircraft. I think just like the Fw-190's (Ta-152) the P-47 was far from the end of its evolution and would have evolved even better then she was.


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## marseille jr (Jun 9, 2005)

Yeps adler. I couldn't agree more here.


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## the lancaster kicks ass (Jun 9, 2005)

does that seem out of context to anyone else??


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## Soren (Jun 9, 2005)

DAVIDICUS said:


> "_ This time we keep it clear what were talking about, so as to avoid any more confusion._"
> 
> Since you want to keep clear what we're talking about, it's the initial climb rate of the P-47N. Alll the "M" and "J" data that we tossed about was for purposes of comparison and extrapolation.
> 
> ...



First of all let me make two small corrections:

*P-47D* 

Max. Engine power is *2535 HP*. (Not 2300 HP)

Power-loading is therefore 5.75 lbs/hp.

----------------------------------------------------------

Now comes my opinion.

Since this debate started I've been searching my books and the internet for data on the P-47M,N,D and XP-47J. What I have found is that all the data is roughly similar to the data below, and that your presented site seems to be unique with its specifications, and therefore I find it slightly unreliable so far. (wouldn't you ?) 

However my #1 reason for doubting some of your presented site's data, is that they just don't add up with the rules of physics and aerodynamics. 

Anyways, on to the -47D and -47N issue....

The data below is roughly consistent with all five of my books, and at least 10 other websites, and AFAIK only your presented website's specifications arent consistent with these numbers:

*P-47M:*

P-47M-1-RE:
Initial climb rate: 3500 feet per minute at 5000 feet and 2650 feet per minute at 20,000 feet.

P-47M:
Initial rate of climb: 3500 ft per minute at 5000 ft and 2650 ft per minute at 20,000 ft

*P-47D:*

_P-47D-25-RE : 
Initial climb rate: 2780 ft/min at sea-level, 1575 ft/min at 30,000ft. 

Climb: 6.2 min to 15,000, 14 min to 30,000.

P-47D-35-RA: 
Max initial climb: 3120 ft/min._ 

*P-47N:*

_P-47N:
Rate of climb: 2770 ft per minute at 5000 ft and 2550 ft per minute at 20,000 ft

P-47N-5-RE:
Initial climb rate was 2770 feet per minute at 5000 feet and 2550 feet per minute at 20,000 feet.

Climb to 25,000 ft in 14.2 minutes._


Now here comes the part where I agree with you...

According to the -47N's overall specifications, it 'should' in theory be climbing slightly faster than the -47D or at least equal to it, but according to the data it doesn't. Now why is that ? Something seems to be wrong with the -47N's data....

I believe the -47N should be climbing with atleast 3,150ft/min+.

The rest of the specifications above on the -47D and -47M, all seem perfectly reasonable to me.


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## DAVIDICUS (Jun 9, 2005)

I am not comfortable with the P-47D's HP at 2,535 as quoted by you. You will find figures quoted from 2,000 to the 2,535 figure across the net and in books. It just doesn't pass the smell test for the following reason.

If the "C" series engine developed only 265 more hp, how could it have propelled the P-47's top speed so high. ("D" 429mph to "N" 467mph where the "N" weighs 1,700lbs more!) The 500hp increase of the "C" series engine over the earlier 2,300hp figure is more reasonable.

How is my presented data unique? I don't think it is and have been careful to source it for you so that you can verify that I am not making it up. 

I have also presented evidence that the paddle blade afforded an additional 400fpm climb rate which you are discounting.

From:http://home.att.net/~jbaugher1/p47_4.html 

_It added 400 feet per minute to the climb rate, but during landings and takeoffs there was only a scant six inches of clearance between blade tips and the ground. Takeoffs and landings must have both been hair-raising. _

At any rate, you are comfortable with the post-paddle blade "D" initial climb rate of 3,120fpm and an initial climb rate forthe "N" of 3,150fpm "plus". 

By "plus" do you mean possibly an additional 350fpm?  

I am just having a hard time swallowing a mere 30fpm increase for the "N" over the "D". And I frankly don't know what "plus" means. Why don't you just come out and say what the figure is that you have in mind?

Again, I do think your hp figure is off. We both have seen a range of hp values ascribed to the P-47D and I think we both can agree that the figure you have selected is the highest either of us has ever seen. To quote you, "... and therefore I find it slightly unreliable so far. (wouldn't you ?)"

How does my data not add up to the rules of physics and aerodynamics? It is you who have offered up a mere additional 265hp on a 1,700lb heavier aircraft as explaination for an increase in speed from 429mph to 467mph.  

Speaking of the rules of physics and aerodynamics, is there any other aircraft that you can think of that could realize such a large increase in performance with an increase of just 265hp even though it is also 1,700lbs heavier? Does this sound like its adding up to the rules of physics and aerodynamics as you say? Is it not more reasonable to accept the also widely cited 2,300hp figure for the "D"?

You saud, "_According to the -47N's overall specifications, it 'should' in theory be climbing slightly faster than the -47D or at least equal to it, but according to the data it doesn't. Now why is that ? Something seems to be wrong with the -47N's data...._" 

I think we have a breakthrough! I have only been arguing this for a while now Soren. I have pointed out time and again that your data shows the "N" model climbing literally slower than the pre-paddle blade "D" data.

Why don't you just tell me what you think the P-47N's initial climb rate would have been based on of your understanding of the post paddle balde "D" and "M" models. Please do not include a "plus". At this point, I really don't care to hash this about anymore so I agree to accept that you and I are not going to agree on this.


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## Soren (Jun 9, 2005)

> How is my presented data unique? I don't think it is and have been careful to source it for you so that you can verify that I am not making it up.
> 
> I have also presented evidence that the paddle blade afforded an additional 400fpm climb rate which you are discounting.



There you go again ! You totally missunderstood me !

I said I found _ your presented site's data to be unique_, in which I meant this site; http://home.att.net/~historyzone/Seversky-Republic7.html (Which you presented us) is unique with some of its data.

I am in no way questioning your credibility DAVID, and I have no reason to, I'm just saying your presented site is not very reliable. 

Geez, you sure have a nack of twisting things   

I'll address the rest later.


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## Soren (Jun 9, 2005)

> I am not comfortable with the P-47D's HP at 2,535 as quoted by you. You will find figures quoted from 2,000 to the 2,535 figure across
> the net and in books.



You won't find 2000 HP with WEP for the -47D in any book DAVID, only 2300HP for the D-20 and 2535HP for the D-35. 

I picked the D-35's WEP power for comparison as it was the D-35 which did 3,120fpm, opposed to the D-20's rate of 2,780fpm.



> It just doesn't pass the smell test for the following reason.



Neither does the P-47M or XP-47J's totally 'unreal' climb figure to 20,000ft !  



> If the "C" series engine developed only 265 more hp, how could it have propelled the P-47's top speed so high. ("D" 429mph to "N" 467mph where the "N" weighs 1,700lbs more!) The 500hp increase of the "C" series engine over the earlier 2,300hp figure is more reasonable.



The P-47 had a low drag wing, which meant that a new prop or a 250 increase in HP would result in a large boost in straight out speed. Prop and engine RPM is also an important factor in this, unfortunately we have no data on the various -47's prop and engine RPM. 



> At any rate, you are comfortable with the post-paddle blade "D" initial climb rate of 3,120fpm and an initial climb rate forthe "N" of 3,150fpm "plus".
> 
> By "plus" do you mean possibly an additional 350fpm?



The -47N's climb rate would offcourse be below the -47M's, but it is possible that it wasnt by that much. I wouldn't be all that surprised if the -47N could do 3,350fpm, but Im more confident it would be around 3,150-3,200fpm.



> I am just having a hard time swallowing a mere 30fpm increase for the "N" over the "D".



Why, it was a good deal heavier, which is more than enough reason.



> And I frankly don't know what "plus" means.



Come on, don't play dumb on me...

"+" means it most likely will not be below the presented figure.



> Why don't you just come out and say what the figure is that you have in mind?



This is all guesses and speculations, nothing more, so its impossible for me to set an exactly accurate figure on it. 



> Again, I do think your hp figure is off. We both have seen a range of hp values ascribed to the P-47D and I think we both can agree that the figure you have selected is the highest either of us has ever seen. To quote you, "... and therefore I find it slightly unreliable so far. (wouldn't you ?)"



The P-47D-20 had 2300HP with WEP, while the P-47D-35 had 2535HP with WEP.



> Speaking of the rules of physics and aerodynamics, is there any other aircraft that you can think of that could realize such a large increase in performance with an increase of just 265hp even though it is also 1,700lbs heavier? Does this sound like its adding up to the rules of physics and aerodynamics as you say? Is it not more reasonable to accept the also widely cited 2,300hp figure for the "D"?



Its not just about HP DAVID, its prop RPM and a variety of other factors aswell. And as I've already explained only the D-20 had 2300HP, the D-35 had 2535HP, and thats fact DAVID.



> You saud, "_According to the -47N's overall specifications, it 'should' in theory be climbing slightly faster than the -47D or at least equal to it, but according to the data it doesn't. Now why is that ? Something seems to be wrong with the -47N's data...._"
> 
> I think we have a breakthrough! I have only been arguing this for a while now Soren. I have pointed out time and again that your data shows the "N" model climbing literally slower than the pre-paddle blade "D" data.



Nope no breakthrough, that has basically been my opinion all the way, but the data available about the -47N kinda ruled it out.



> Why don't you just tell me what you think the P-47N's initial climb rate would have been based on of your understanding of the post paddle balde "D" and "M" models. Please do not include a "plus". At this point, I really don't care to hash this about anymore so I agree to accept that you and I are not going to agree on this.



It would be somewhere around 3,150-3,300fpm if you ask me, 3,300fpm being a very optimistic figure.

Can you agree with that ? 

I think we can both agree that it won't be as high as the -47M's figure, or what ?


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## Soren (Jun 9, 2005)

And a quote:

_The P-47B and C models were fine high altitude fighters. The P-47B had a top speed of 406 mph at 27,000 ft., an excellent rate of roll, and could dive like a stone. The Thunderbolt had great survivability; it could absorb a lot of punishment and still get home. The best climb rate was unimpressive, however, at only 1,650 ft./min at SL

By early 1943 the P-47D was coming off the production lines. The P-47D was produced in higher quantity than any other model, and in many variations. Early "D" models were similar to the previous "C" model, with only detail improvements, but as production progressed the "D" model continued to be improved. Republic built a total of 12,602 P-47D's. In addition, Curtis-Wright built 354 P-47D's under license as the P-47G. 

P47D-6-RE to P-47D-11-RE models came with an under fuselage shackle for a 500 lb. bomb or a drop tank. Subsequent models, up to the P-47D-20-RE, had strengthened wings with under wing pylons and were able to carry a 1,000-pound bomb under each wing. 

The "universal wing," which could carry a variety of stores, was introduced with the P-47D-20-RE. A large four-bladed "paddle" propeller was also fitted. This, along with the water-injection R-2800-21 engine, which had a war emergency rating of 2,300 hp, markedly improved the maximum rate of climb, which was now up to 2,750 ft./min. at 5,000 ft. 

The P-47D-25-RE and subsequent models had a cut down rear fuselage and a teardrop canopy, adapted from the British Typhoon fighter. Internal fuel capacity was also increased. The R-2800-59 engine had a war emergency rating of 2,535 hp. Climb rate was now up to 3,120 ft./min., and top speed was 426 mph at 30,000 ft. The Thunderbolt had basically reached full flower.

The next variant to achieve series production was the P-47M. This was called the "sprint" model, and it was a response to the jet powered German V-1 "Buzz Bomb" cruise missile, and the German jet fighters. It had an up-rated R-2800-57(C) engine and CH-5 turbocharger system, which gave a top speed of 470 mph at 30,000 ft. Initial climb was 3,500 ft./min. Delivered beginning in December 1944, 130 were produced.

The last P-47 variant to achieve series production was the P-47N. This model was designed specifically for the pacific theatre, where very long range was a requirement. The "N" used the same engine as the "M"; late production models received the P-2800-77 engine. A new, stronger, wing with squared tips was designed, which incorporated eight internal fuel cells. The landing gear was strengthened to deal with the increased weight of the aircraft. From the P-47N-5-RE model on, zero length rocket launchers were added beneath the wings. 

Habitability improvements included an automatic pilot, an armchair seat, and folding rudder pedals to give the pilot increased leg room. These improvements were intended to increase the pilot's comfort on long escort missions. 

Maximum speed was 467 mph at 32,500 ft. Initial climb was 2,770 ft./min., and the range on maximum internal fuel was 2,350 miles. The P-47N saw extensive use in the last months of the Pacific War, and had the range to escort the B-29's all the way from Saipan to Japan. Between December 1944 and December 1945 a total of 1,816 P-47N's were manufactured. _


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## DAVIDICUS (Jun 9, 2005)

You have posted some really interesting data out on the D-25. 

_The P-47D-25-RE and subsequent models had a cut down rear fuselage and a teardrop canopy, adapted from the British Typhoon fighter. Internal fuel capacity was also increased. The R-2800-59 engine had a war emergency rating of 2,535 hp. Climb rate was now up to 3,120 ft./min., and top speed was 426 mph at 30,000 ft. The Thunderbolt had basically reached full flower.

The "N" was tested in mock combat against the D-25.

From: http://home.att.net/~historyzone/Seversky-Republic8.html 

Test comparisons were made with a P-47D-30-RE throughout the early portion of the evaluation period. Much to everyone’s surprise, the XP-47N, with its greater wingspan and higher weight actually proved to have better roll performance than the D model. At 250 mph TAS, the N attained a maximum roll rate just over 100 degrees/second. The P-47D-30-RE could manage but 85 degrees/second at the same speed. At higher speeds, the N widened the gap further.

*In mock combat with a P-47D-25-RE, the new fighter proved to be notably superior in every category of performance*. In short, the XP-47 waxed the venerable D model regardless of who was piloting the older fighter. The new wing was part of this newfound dogfighting ability, however, the more powerful C series engine played a role too. The additional horsepower allowed the N to retain its energy better than the older Thunderbolt.

Perhaps the greatest performance increase was in maximum speed. Though not as fast as the stunning P-47M, the heavier N was fully 40 mph faster than the P-47D-25-RE and could generate speeds 30 mph greater than its principal rival, the Mustang. Scorching along at 467 mph @ 32,000 ft., the N could not be caught by any fighter in regular service with any air force on earth with the single exception of its M model sibling. This combination of wing and engine had pushed the N model up to the top rank of the superlative prop driven fighters then in existence.

I assume that by, "... the new fighter proved to be notably superior in every category of performance." it was meant that the climb rate was superior as well._


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## DAVIDICUS (Jun 9, 2005)

Soren, I don't know what books you have at home regarding the P-47M. That data I presented from: http://www.geocities.com/pentagon/quarters/9485/P-47M.html was cited from the following publications:

Warren M. Bodie, Republic's P-47 Thunderbolt

Roger Freeman, Republic Thunderbolt

Enzo Angelucci and Peter Bowers, The American Fighter

David R. McLaren, Beware The Thunderbolt: The 56th FG in WWII


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## Soren (Jun 9, 2005)

DAVIDICUS said:


> Soren, I don't know what books you have at home regarding the P-47M. That data I presented from: http://www.geocities.com/pentagon/quarters/9485/P-47M.html was cited from the following publications:
> 
> Warren M. Bodie, Republic's P-47 Thunderbolt
> 
> ...



It wasnt cited from Warren M.Bodie's book thats for sure !


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## DAVIDICUS (Jun 9, 2005)

Why do you say that?

I don't have the book myself. I am just relaying what the website states at the bottom.


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## Soren (Jun 9, 2005)

DAVIDICUS said:


> Why do you say that?



Cause much of my presented data is from that book.


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## Soren (Jun 10, 2005)

Anyway lets get on with the discussion...

Since you asked me I will ask you; DAVID what do you speculate the -47N's climb rate to be ? Can you agree with my result ?


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## DAVIDICUS (Jun 10, 2005)

I think your data on the horsepower may be correct after all. 

I'm not really sure what to make of the climb rate. I'm inclined to believe that the performance of the "N" model was "notably superior in every category of performance" to the D-25 per my cited passage.

I'll give it some thought.


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## DerAdlerIstGelandet (Jun 10, 2005)

Wow that is a lot of info to take in at one time. I am going to have to compare it to some info that I have in my books.


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## FLYBOYJ (Jun 10, 2005)

Great stuff, it was fun trying to follow it all. Constructive criticism - just remember, if you show performance data try to show MP, RPM HP, or at least MP and RPM. In performance charts I've dealt with its hard to grasp real performance with one of those parameters missing.


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## DerAdlerIstGelandet (Jun 10, 2005)

Very true.


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## DAVIDICUS (Jun 10, 2005)

I found some rpm data on the "N" model. The data comes literally from the Pilot Training Manual itself.

Maximum continuous (Normal rated power) 2,600rpm @ 43.5"

Takeoff (military power) 2,800rpm @ 54"

War emergency power 2,800rpm @ 72"

The engine can be overspeeded to 3,120rpm for up to 30 seconds without damaging the engine.

I also found some other interesting imformation.

Weight: empty - 10,998lbs. Useful load varies from 2,824 to 10,199.9lbs.  

Wing Area: 322.2 sq. ft. giving a *wing loading of approximately 43 lbs sq. ft. with normal gross weight 13,854lbs*.

The manual I am citing to above, by the way, can be downloaded at:
http://www.lanpartyworld.com/ww2/files/air-manuals/usaaf/

I think we have been laboring under an erroneous assumption about the weight of the "N" model. We have assumed that the "N" model was necessarily heavier under all loading conditions than the "D" model. I think this assumption came about because the maximum loaded weight that the P-47N could take off at was in excess of 20,000lbs.

With respect to the "D" model (all versions, in fact) I am seeing referenced normal loaded weights in excess of the "N" model's normal gross weight iof 13,854lbs. 

I would suggest (pursuant to the Pilot Training Manual) that the more powerful engine, larger wing and lighter weight of the "N" allowed for the greater fuel and armament loadings of the "N" model and that the "N" model was not, in fact, heavier in normal gross weight than the "D".

Following this line of thought, the "N" model's more powerful "C" series engine, lighter weight and larger wing area would have put the climb rate significantly (what "significantly" means is still in question) above the D-25RE as well as explain how the top speed rocketed to 467mph. 

On a related note, this also coincides with the "M" model having a similar normal loaded weight of 13,275lbs and similar top speed that was achieved with the same "C" series powerplant.


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## DAVIDICUS (Jun 10, 2005)

The P-47M was a modified D-27 model. The wing area for all the "D" models was 300sq. ft. as there was no alteration of the wingspan or wing area throughout the evolution of the "D" series.

In light of the data from the actual Pilot Training Manual itself which constitutes a primary data source, the following comparison emerges vis a vis the "M" and "D" data.

------------------------------------------------------------

P-47N

Wing area - 322.2 sq.ft.

Normal gross weight - 13,854 (Wing loading - 43lbs)

Horsepower - 2,800 (Power loading - 4.94lbs)

Initial climb rate - ?

P-47M

Wing area - 300 sq.ft.

Normal loaded weight - 13,275 (Wing loading - 44.25lbs)

Horsepower - 2,800 (Power loading - 4.74lbs)

Climb rate at 5,000ft is 3,500fpm (I am assuming this for the purposes of furthering the discussion. In addition, even accepting the 3,500fpm figure at 5,000ft would mean a higher initial climb rate)

P-47D-25

Wing area - 300 sq.ft.

Normal Loaded weight - 14,600lbs (Wing loading - 48.67lbs)

Horsepower - 2,535 (Power loading - 5.76lbs)

Initial climb rate is 3,120fpm.

----------------------------------------------------

I think that if the "D" climb rate is correct (I always thought it was 2,780 + 400fpm which would be 3,180fpm but I will not contest over 60fpm), then the "M" figure would have to be higher than 3,500fpm for initial climb rate. It is in any event because the 3,500fpm figure is for 5,000ft and not an initial figure.

Correspondingly, the "N" model would be very close to the "M" and certainly well in excess of 3,150fpm. I also believe it would be in excess of the 3,300fpm figure that was offered to make me happy as well.  

To recap:

The power loading of the "D" vs. "N" is 5.76lbs vs. 4.94lbs (14.2% decrease in lbs. per hp.)

The wing loading of the "D" vs. "N" is 48.67lbs vs. 43lbs. (11.6% decrease in lbs. per sq.ft.)

Accepting 3,500fpm as an initial climb rate for the "M", we can extrapolate how such differences in power and wing loadings would affect climb rate.

The power loading of the "D" vs. "M" is 5.76lbs vs. 4.74lbs (17.7% decrease in lbs. per hp.)

The wing loading of the "D" vs. the "M" is 48.67lbs vs. 44.25lbs (9% decrease in lbs. per sq.ft.)

Even under the data you offered Soren, the "M" would have an initial climb rate in excess of 3,500fpm and the "N" would be very, very close. Of course, if the "M" has a greater than 3,500+fpm climb rate, then the "N" follows accordingly.


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## Soren (Jun 11, 2005)

If we suppose the -47M's climb figure is correct , which it should be according to its power and wing-loading, and we suppose that DAVID's newly found weight figure is correct aswell, then I would actually rate the -45N's climb rate either very close to, or as 3,500fpm. (=equal to the the -47M)

If the -47N uses the same prop and engine, and is only slightly heavier than the -47M, but additionally has a larger wing, then the -47N 'should' be climbing either very close or equal to the -47M. (Maybe 3,450-3,500fpm) 

However what I'm questioning most at the moment, is why should the data from several books about the P-47 be wrong about the -47N's normal loaded weight figure ? Seems strange...

The -47N's normal loaded weight is quoted as being 16,300 pounds by every single one of my sources. That's allot more than 13,850lbs !

------------------------------

So my conclusion is:

If we use the DAVID's newly acquired weight figure for the -47N, then it should be climbing at very close to 3,500ft/min. 

But if we use what is the most common weight figure for the -47N, then I would guess the climb rate as being somewhere between 3,150-3,200ft/min.


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## DerAdlerIstGelandet (Jun 11, 2005)

Id typically go with the most common figures for anything. Simple strenght in numbers.


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## DAVIDICUS (Jun 11, 2005)

Often, the most common figures cited in published sources are derived from the same "other sources." (We've all seen erroneous figures relied on and published in multiple venues.)

That' why primary source documents are so important. The chance that the Army Air Force's own flight manuals would be based on erroneous data is mitigated as the Army Air Force is the primary and direct source repository of the data itself. 

There is no chain of custody issue to deal with where a figure is based on a source that is cited from another source that purports to be based on official primary source data. The Army Air Force doesn't have to search the "web" and books for data to base performance figures on. They merely consult the original data that was collected.

The Army Air Force is also in the best position to catch and correct mistakes either clerical or substantive in nature. Manuals aren't released without creful editing for errors and substantively erroneous data is caught because it is the Army Air Force that uses that same primary source data in determining and checking performance data in other tests. For instance, a substantive error that places a wing loading at 40lbs is more likely to raise eyebrows when actual performance tests indicate that it ought to be 35lbs.


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## DerAdlerIstGelandet (Jun 11, 2005)

I will agree with you here, the best souce is the direct manual itself.


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## wmaxt (Jun 11, 2005)

Of course the data in the flight manuals is also "Hedged" or conservitive so that an average pilot in an average plane with average maintenance and flight hours can expect. For example in the P-38 manual the highest power setting shown for a L model is 1,600hp @ 60"hg, even though at 64"hg it could pull 1,725hp.
Two profiles are shown for climb performance, Ferry and Combat climb. Combat Climb is only 1,100hp (CORRECTION 54"hg is 1,425hp) @ 54"hg and 3,000 rpm (METO power not normal) the climb is at optium climb angle for 3,200ft/mn initial. these numbers are not even close to the maximum available.
Also all, time, numbers are rounded for simplicity

So yes the manuals are great sources but may not be difinitive either.

wmaxt


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## DerAdlerIstGelandet (Jun 11, 2005)

The manuals normally show the safe operating limits.


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## wmaxt (Jun 11, 2005)

DerAdlerIstGelandet said:


> The manuals normally show the safe operating limits.



Thats true. It's also true that performance figures are "averaged" to fit aircraft in normal (not new) condition. The limits are also fudged for purposes of economy in peace time as well. I have a 1954 t-1 flight manual for the P-51 and there are a number of perameters that are lower than combat conditions would even consider. 

If a pilot jumps in his plane and can exceed the flight manual a bit he's going to be very happy with his aircraft. If he jumps in and can't achieve his expectations you will have a pilot who detests his aircraft and the maintenance crew he bets his life on. As you point out the safe operating envelope is listed but it must also fit the average age and maintenance of the aircraft. Last the data must be reliable enough to allow mission profile and planning to be acceptable for all the aircraft involved, even the one in the poorest condition. Things like range can be dependant the pilot/outside influences.

All I'm really saying is that the flight manual is a good place to start defining the normal performance envelope of an aircraft but it will not give you the maximum performance envelope. It's dependent on too many things.

One thing we all do here is use new/optimum figures to compare aircraft. There are to many variables to compare anything else but we need to keep that in mind.

wmaxt


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## DerAdlerIstGelandet (Jun 11, 2005)

You also have to remember that the aircraft could exceed the normal limits anyhow, well atleast if the aircraft was maintained properly.


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## wmaxt (Jun 11, 2005)

DerAdlerIstGelandet said:


> You also have to remember that the aircraft could exceed the normal limits anyhow, well atleast if the aircraft was maintained properly.



Exactly  

wmaxt


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## DerAdlerIstGelandet (Jun 11, 2005)

wmaxt said:


> One thing we all do here is use new/optimum figures to compare aircraft. There are to many variables to compare anything else but we need to keep that in mind.
> 
> wmaxt



True to this also.


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## Jank (Jun 11, 2005)

flight manuals are the holy grail No disrespect intended.

Hard to argue with the owners manual when it comes from the owner himself.!


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## DerAdlerIstGelandet (Jun 11, 2005)

Yes but what we are saying is the Owners Manual only tells you the safe operating procedures. Normally there is an appendix that will tell you the max limits of your aircraft but the normal performance values and limits are for safe operation.

Atleast thats the way it is with my aircraft and the other aircraft I have delt with.


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## Sal Monella (Jun 11, 2005)

I'm not sure I understand. Are you saying that actual test data for maximum figures would be higher than performance figures in a manual?


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## Nonskimmer (Jun 11, 2005)

Quite possibly. Manuals will normally list nominal performance characteristics only. This hopefully keeps the operator from doing something foolish, but it's good to have the added capability that comes from a well built, well maintained machine.


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## Soren (Jun 12, 2005)

While it is true that performance figures in pilot flight manuals can be "underrated", the weight figures in such manuals shouldn't be rated lower or higher than usual.


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## the lancaster kicks ass (Jun 12, 2005)

but remeber as well that it was uncommon for planes to fly at full power for any realy length of time, we talk about planes speeds using their top speeds when they would very rarely hit this........


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## DAVIDICUS (Jun 12, 2005)

To reiterate, "While it is true that performance figures in pilot flight manuals can be "underrated", the weight figures in such manuals shouldn't be rated lower or higher than usual."

To the extent that they should not be lower or higher, they would be accurate. And following this, should be accepted as accurate.


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## Soren (Jun 12, 2005)

DAVIDICUS said:


> To reiterate, "While it is true that performance figures in pilot flight manuals can be "underrated", the weight figures in such manuals shouldn't be rated lower or higher than usual."
> 
> To the extent that they should not be lower or higher, they would be accurate. And following this, should be accepted as accurate.



Yes it would seem that way, but its hard to believe that so many researchers got it so horribly wrong though. Something is fishy about that manual....

Anyway, if the manual's weight figures are correct then the -47N 'should' be climbing at something like 3,450-3,500 ft/min, the same as the -47M. And if the figures aren't correct, well then it would most likely be climbing at something like 3,150-3,200 ft/min.


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## FLYBOYJ (Jun 12, 2005)

Soren said:


> Yes it would seem that way, but its hard to believe that so many researchers got it so horribly wrong though. Something is fishy about that manual.....



This was discussed in another thread. Sometimes engineers place between 2-5% "governor" factor in some aircraft performance numbers, just so if there is an expedience, the plane isn't being readily destroyed.


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## Soren (Jun 12, 2005)

FLYBOYJ said:


> Soren said:
> 
> 
> > Yes it would seem that way, but its hard to believe that so many researchers got it so horribly wrong though. Something is fishy about that manual.....
> ...



Which has what to do with "weight" figures ?  

We're talking weight figures here, not engine performance figures


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## FLYBOYJ (Jun 12, 2005)

Soren said:


> FLYBOYJ said:
> 
> 
> > Soren said:
> ...



 Sorry my mistake, but I would also add weight to that factor. Look at aircraft weights and maneuving speeds. The heavier the aircraft is, the more it rough air penatration and Gs it could take. This is shown in the -1s. I would think that engineers would factor these numbers in so a pilot won't takke a lightly loaded aircraft and start putting excessive Gs on the airframe.


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## Soren (Jun 12, 2005)

But how does this explain a 3,000lbs drop in the "normal" loaded weight figure ?

Engineers might add limiting factors for whatever weight-configuration, but they wouldnt alter the "Normal loaded" weight figure, as thats impossible.


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## FLYBOYJ (Jun 12, 2005)

Soren said:


> But how does this explain a 3,000lbs drop in the "normal" loaded weight figure ?
> 
> Engineers might add limiting factors for whatever weight-configuration, but they wouldnt alter the "Normal loaded" weight figure, as thats impossible.



Yea, that does sound a bit funny. You might want to double check these manuals and figures and make sure there isn't a caveat for armor or equipment removed. I've seen empty weights shown in some aircraft with armament, armor, all fluids and radios removed.


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## Soren (Jun 12, 2005)

FLYBOYJ said:


> Soren said:
> 
> 
> > But how does this explain a 3,000lbs drop in the "normal" loaded weight figure ?
> ...



You have a very good point there FLYBOYJ !


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## DAVIDICUS (Jun 12, 2005)

Soren said, "_Something is fishy about that manual.... _"

In light of the manual, I think the other data is fishy. It is the manual after all. For one thing, we don't know where where the other data came from. 

Soren said, "_But how does this explain a 3,000lbs drop in the "normal" loaded weight figure ?_"

Soren, it isn't 3,000lbs. We're talking 16,300 as opposed to 13,854lbs. (That's about 2,500lbs but I guess it helps your position if you round up.)

Flyboy said, "_Yea, that does sound a bit funny.  You might want to double check these manuals and figures and make sure there isn't a caveat for armor or equipment removed. I've seen empty weights shown in some aircraft with armament, armor, all fluids and radios removed_."

Done. Double checked for any such caveat. None. Speaking of checking the manual, you can check it for yourself as I posted the web link to the actual manual itself. On another note, why would they present data in the pilots manual for a different configuration than would be used? The operative figure here is *normal gross weight* and in any event, the figure for "normal gross weight" would not be subject to conditions where the armor, armament, fluids and radio are removed.

Moreover, if the empty weight is sans armor, armament, fluids and radio, it would make the "normal gross weight" figure stand out as clearly incorrect because the normal gross weight would include these items in addition to a normal fuel and armament loading.

As Soren himself said, "_Engineers might add limiting factors for whatever weight-configuration, but they wouldnt alter the "Normal loaded" weight figure, as thats impossible_."

Soren said, "_Anyway, if the manual's weight figures are correct then the -47N 'should' be climbing at something like 3,450-3,500 ft/min, the same as the -47M. And if the figures aren't correct, well then it would most likely be climbing at something like 3,150-3,200 ft/min_."

Well Soren, if the P-47M has an initial climb rate of 3,500fpm (which it does not as that figure is for 5,000ft.) than I would say you are correct but:

If the 3,500fpm figure at 5,000ft is correct, then the initial climb rate would be more like 3,600-3,650fpm (maybe as high as 3,700fpm) puting the "N" model's at 3,550-3,600fpm (maybe as high as 3,650fpm). (Please revisit the correct power and wing loading figures for the "M" and "N" below)
--------------------

P-47M

Wing area - 300 sq.ft.

Normal loaded weight - 13,275 (Wing loading - 44.25lbs)

Horsepower - 2,800 (Power loading - 4.74lbs) 

P-47N

Wing area - 322.2 sq.ft.

Normal gross weight - 13,854 (Wing loading - 43lbs)

Horsepower - 2,800 (Power loading - 4.94lbs) 
--------------------

As you may recall, you said you were getting us back on the subject by citing the following data for the "M" in your post on page nine of this thread:

_P-47M:

P-47M-1-RE:
Initial climb rate: *3500 feet per minute at 5000 feet* and 2650 feet per minute at 20,000 feet.

P-47M:
Initial rate of climb: *3500 ft per minute at 5000 ft* and 2650 ft per minute at 20,000 ft_

If the initial climb rate of the "M" is higher, which I believe to be the case, then the P-47N's initial climb rate will follow accordingly. I have located someone who supposedly has some documented performance data from Republic Aviation concerning the performance of the "M" and "N" models. He said that he recalls that the "M" model's climb rate was about 3,750fpm. (he did not recall the altitude). If and when I obtain this performance data from Republic Aviation, I will share it on the forum. I will not represent his memory of data to be fact.

Stay tuned.


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## Soren (Jun 13, 2005)

> Soren said, "_But how does this explain a 3,000lbs drop in the "normal" loaded weight figure ?_"
> 
> Soren, it isn't 3,000lbs. We're talking 16,300 as opposed to 13,854lbs. (*That's about 2,500lbs but I guess it helps your position if you round up*.)



This is a case of; "I remembered the manual's figure as 13,300lbs but it wasnt." Big deal, get over it DAVID, and don't start accusing people right away. 

A 2,500lbs drop in weight is equally unrealistic...



> If the 3,500fpm figure at 5,000ft is correct, then the initial climb rate would be more like 3,600-3,650fpm



Oh really, please explain why ? 

Just remember before you say anything, it says "Initial" climb rate at 5,000ft


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## DAVIDICUS (Jun 13, 2005)

"_A 2,500lbs drop in weight is equally unrealistic..._"

I have provided you with the pilot's manual itself Soren. It is what it is and that is a primary source of reliable data. That being the case, we can now assume that the 2,554lb (aka 2,500lb) drop in weight is not "unrealistic" but fact. If you want to continue to profess doubts in order to to assuage your ego in light of the erosion of your position, that is up to you. I will certainly not stand in the way of your maintaining an "unrealistic" position. 

"_Oh really, please explain why?_"

Because that could very well be the rate of climb at 5,000 feet which would not be the rate of climb at 500 or 1,000 feet. It doesn't matter if you call it "initial" or "starting" or "beginning." Whatever modifier you place before "at 5,000 feet" doesn't change the fact that it is a figure, and I quote, *at 5,000 feet*.

From: http://www.spitfireperformance.com/spit9.html

_Spitfire Mk. IX @ 25lbs of boost

Climb rate at 0ft - 5,740ft.

Climb rate at 5,000ft - 5,080ft._

Do you notice the drop in the rate of climb between 0ft and 5,000ft? If we didn't have the 0ft figure and started with the 5,000ft figure, and called it "initial," that would not change the fact that the climb rate has already dropped significantly between 0ft and 5,000ft.

Now, if on the other hand, we were to take the average of the climb rate from 0ft to 5,000ft and then call that "initial," my point would still hold fast. The averaged rate of climb from 0ft to 5,000ft would still be lower than the actual climb rate at 0ft.

At best, you could hope for the latter example as an explaination of the "initial" climb rate "at 5,000ft." I gave the data for the Spitfire Mk. IX only to drive home my point. I think that the actual increase in the "M" model's initlal climb rate, assuming your 3,500fpm figure, would be less as evidenced by the estimates I provided.


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## Soren (Jun 13, 2005)

> "_A 2,500lbs drop in weight is equally unrealistic..._"
> 
> I have provided you with the pilot's manual itself Soren. It is what it is and that is a primary source of reliable data. That being the case, we can now assume that the 2,554lb (aka 2,500lb) drop in weight is not "unrealistic" but fact.



DAVID didnt you read what I said earlier ? I said: _Engineers might add limiting factors for whatever weight-configuration, but they wouldn't alter the "Normal loaded" weight figure, as thats impossible._

Now what part of this did you miss ?



> If you want to continue to profess doubts in order to to assuage your ego in light of the erosion of your position, that is up to you. I will certainly not stand in the way of your maintaining an "unrealistic" position.



DAVID I don't need those insults, they're good for nothing. Why would you say something like this ? Can't you stand that someone doubts the highest performance figure of your precious P-47, is that it ? well then sorry, it won't happen again  

No seriously DAVID, you don't need to be so aggressive, I've never insulted you, so I don't need such remarks.



> Because that could very well be the rate of climb at 5,000 feet which would not be the rate of climb at 500 or 1,000 feet. It doesn't matter if you call it "initial" or "starting" or "beginning." Whatever modifier you place before "at 5,000 feet" doesn't change the fact that it is a figure, and I quote, *at 5,000 feet*.



The word "Initial" is put there for a reason DAVID, and aswell is left out for a reason on the presented Spit IX data.  



> From: http://www.spitfireperformance.com/spit9.html
> 
> _Spitfire Mk. IX @ 25lbs of boost
> 
> ...



You will note from the same site: 
_Max. rate of climb at full throttle height in M.S. supercharger gear 4470 ft/min. (*at 11,200 ft*.) 
Max. rate of climb at full throttle height in F.S. supercharger gear 3400 ft/min. (*at 22,700 ft*.) _
=Initial climb rate.


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## DAVIDICUS (Jun 13, 2005)

I'm not sure what your point is with respect to your saying, "_Now what part of this did you miss?_"

As a reminder, you said, "_But how does this explain a 3,000lbs drop in the "normal" loaded weight figure?_" 

I pointed out that the reduction in weight was really about 2,500lbs (2,554lbs to be exact) to which you replied that even that reduction was, "... _equally unrealistic_... "

I then responded that, "I have provided you with the pilot's manual itself Soren. It is what it is and that is a primary source of reliable data. That being the case, we can now assume that the 2,554lb (aka 2,500lb) drop in weight is not "unrealistic" but fact."

Thus, I was under the impression that you found the 2,554lb (which you had represented to be 3,000lb) reduction of weight "unrealistic" per your own statement. If that is not the case and you no longer or otherwise do not find the reduction in weight "unrealistic," in light of the data presented directly from the pilot's manual, then I apologize and am pleased that we are now in agreement.

Now, when I quoted you as saying, ""Engineers might add limiting factors for whatever weight-configuration, but they wouldnt alter the "Normal loaded" weight figure, as thats impossible.", I was responding to Flyboy. So to quote you again, "What part of this did you miss?"

I think my point about degradation of climb rate from 0ft to 5,000ft still stands. As I clearly pointed out, "I gave the data for the Spitfire Mk. IX only to drive home my point." Thus it was just an illustrative example.

Your quoted specifications appear on the website as: 

*Max rate of climb at full throttle in M.S. supercharger gear 4,470 ft/min. (at 11,200ft.)

Max rate of climb at full throttle in F.S. supercharger gear 3,400 ft/min. (at 22,700ft.)*

I do not understand your reference to "=_Initial climb rate_." I'm not sure how this relates to my point concerning the degradation of climb rate from 0ft to 5,000ft which again was:

_Spitfire Mk. IX @ 25lbs of boost 

Climb rate at 0ft - 5,740ft. 

Climb rate at 5,000ft - 5,080ft._

At any rate, if my point, as opposed to my example, is flawed, please explain. Otherwise, it is the point as opposed to the example that would apply to the "M" model's actual initial vs. "initial at 5,000ft" climb rate.


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## DerAdlerIstGelandet (Jun 13, 2005)

Sal Monella said:


> I'm not sure I understand. Are you saying that actual test data for maximum figures would be higher than performance figures in a manual?



Yes the manufacturer and in some cases the military (normally after something bad happens) places limits on the aircrafts performance. The aircraft can perform better than these limits if need be but the limits are placed there to keep the pilot from doing something stupid. 

Now in combat limits being exceeded is not uncommon. Many times the pilot exceeding the limits gets the kill.


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## DAVIDICUS (Jun 13, 2005)

Or alternatively, gets to keep from being killed.


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## DerAdlerIstGelandet (Jun 13, 2005)

Yeap that is another way of putting it.


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## Soren (Jun 13, 2005)

I can see we missunderstood each other, "Again".  



> I'm not sure what your point is with respect to your saying, "_Now what part of this did you miss?_"
> 
> As a reminder, you said, "_But how does this explain a 3,000lbs drop in the "normal" loaded weight figure?_"



Which was pointed at the official books about the P-47, not the manual. What I couldnt understand was how so many serious researchers got it so horribly wrong, and I still don't understand how.



> I pointed out that the reduction in weight was really about 2,500lbs (2,554lbs to be exact) to which you replied that even that reduction was, "... _equally unrealistic_... "



It is unrealistic, as engineers would never reduce or add to the normal loaded weight figures in flight manuals. (Performance figures is another matter)



> I then responded that, "I have provided you with the pilot's manual itself Soren. It is what it is and that is a primary source of reliable data. *That being the case, we can now assume that the 2,554lb (aka 2,500lb) drop in weight is not "unrealistic" but fact."*



Presumably yes, but I'm just abit puzzled by the fact that so many researchers got it so horribly wrong, thats all. 



> Thus, I was under the impression that you found the 2,554lb (which you had represented to be 3,000lb) reduction of weight "unrealistic" per your own statement.



I do find it unrealistic, as that manual 'should' be correct. The engineers would never play with the weight figures, however with authors your just never 100% sure. But that 'so many' serious researchers should be wrong about the weight figures, seems quite strange to me, and makes the manual seem a little fishy, as the researchers presumably relied on manuals to get their figures themselves.



> If that is not the case and you no longer or otherwise do not find the reduction in weight "unrealistic," in light of the data presented directly from the pilot's manual, then I apologize and am pleased that we are now in agreement.



Apology accepted. Now I will apologize for not making myself perfectly clear on what really meant.



> Now, when I quoted you as saying, ""Engineers might add limiting factors for whatever weight-configuration, but they wouldnt alter the "Normal loaded" weight figure, as thats impossible.", I was responding to Flyboy. So to quote you again, "What part of this did you miss?"



Probably all of it, I was in quite a hurry when I read it.  



> I think my point about degradation of climb rate from 0ft to 5,000ft still stands. As I clearly pointed out, "I gave the data for the Spitfire Mk. IX only to drive home my point." Thus it was just an illustrative example.



Ok, I'll explain why not below.  



> Your quoted specifications appear on the website as:
> 
> *Max rate of climb at full throttle in M.S. supercharger gear 4,470 ft/min. (at 11,200ft.)
> 
> ...



Look at my presented figures and then look at yours, then you will see that mine are presented as Max climb rate's at certain altitudes, yours are not. And as we both know an a/c has different speeds and climb rates at different altitudes. 

Now the word "Initial" virtually means "beginning" or "Start of", and at 5,000ft the -47M will have a climb rate of 3,500ft/min in the beginning or at "the start of" the climb = the max climb rate at that altitude.

Also you will note the alt difference between my figures is 10,500ft(11,200-22,700ft) but only 970ft/min in climb rate, while the difference between your figures is much higher considering its a lower alt difference "5,000ft".

Take for example this quote from the same site:

_Rate of climb at Sea level: 
Spitfire IX BS. 543 Merlin 66= *4620 ft/min. *
Spitfire IX BS. 551 Merlin 70= *4390 ft/min. *

Spit IX Merlin 66: Rate of climb at full throttle height in M.S. supercharger gear= *4700 ft/min at 7000 ft. *
Spit IX Merlin 70: Rate of climb at full throttle height in M.S. supercharger gear= *4530 ft/min. at 11,900 ft.* 
Spit IX Merlin 66: Rate of climb at full throttle height in F.S. supercharger gear= *3860 ft/min. at 18,000 ft.* 
Spit IX Merlin 70: Rate of climb at full throttle height in F.S. supercharger gear= *3480 ft/min. at 24,700 ft.*_

Now the if we were to follow your example/point the Spit IX would suddenly be climbing faster than from sea level when it reaches 7000ft, which we both know isn't the case.

---------------------------------

Well this is all I have time for right now, but I'll be back later. 
And please excuse any mess in the writing, as I was in quite a hurry writing this.


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## DAVIDICUS (Jun 13, 2005)

"_Look at my presented figures and then look at yours, then you will see that mine are presented as Max climb rate's at certain altitudes, yours are not._"

I do see this but am not sure what the consequence is. Under what circumstances would you present "climb rate" if not intending to, present "maximum climb rate?" Isn't that just understood? What value would it be to have a chart that lists the "climb rate" at say 5,000ft at a lower speed and angle of climb and a "climb rate" at say 10,000ft at a higher speed and angle of climb? Or for that matter, why would anyone be interested in a climb rate that reflects a slow leisurely climb? I believe this is why we can assume that the data I provided was in fact for maximum climb rate (or are you saying that a Mk. IX at 25lbs of boost could do better?)

In keeping with this, the data I provided was in fact for maximum climb rate even though it didn't expressly say "maximum.":

*Spitfire Mk. IX @ 25lbs of boost 

Climb rate at 0ft - 5,740ft. 

Climb rate at 5,000ft - 5,080ft. *

I agree with you that, "_Now the word "Initial" virtually means "beginning" or "Start of", and at 5,000ft the -47M will have a climb rate of 3,500ft/min in the beginning or at "the start of" the climb = the max climb rate at that altitude._"

That being the case, when you presented P-47M climb data as "_initial climb at 5,000ft_" you were indeed presenting the "_maximum climb rate at that (5,000ft) altitude_."

Therein lies my point. I am concerned that if we compare the initial climb rate of the "N" model at a far lower altitude than 5,000ft, say sea level, we would be comparing apples to oranges. If the P-47M can start a climb at 5,000ft at a rate of climb of 3,500fpm (again, I am just assuming this figure for purposes of this discussion), then the P-47N, to be fair, would need to be tested in its start of its climb at 5,000ft as well. 

If we assume a 3,500fpm maximum initial climb rate at 5,000ft for the "M" model, it stands to reason that that same "M" model aircraft could deliver a higher maximum initial rate of climb at sea level and a lower maximum initial rate of climb at 10,000ft and still lower at 20,000ft. Had you presented a maximum initial climb rate at 10,000ft or 20,000ft, I would thus be making the same argument. 

*To further the point of this example, it should be quite obvious to see that the "M" would have a higher "initial climb rate" at 5,000ft than at 20,000ft and that it would not be helpful to use the 20,000ft figure simply in order to depress the estimates of the "M" model's initial climb rate so that the "N" model's initial climb rate would be similarly depressed in a debate where you have taken the position that the climb rates are lower. Likewise, the 5,000ft figure you are in fact using is lower than the figure would be at sea level.*

Hence, when I speak of "maximum initial climb rate" I want to be comparing apples to apples by comparing "maximum initial climb rates" at the same altitude in which the maximum climb rate can be achieved.

If the "M" model can pull 3,500fpm at 5,000ft, it could pull better than that at sea level. If we compare the "M" model at 5,000ft and the "N" model at sea level, we could very well see the "N" model's climb rate exceed the "M" model's 5,000ft maximum climb rate.


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## Soren (Jun 14, 2005)

I see what you mean DAVID, but not all a/c will have better climb rates down low though, but thats another matter. 

However since the -47N and -47M used the same C engine, their engine performance curve at altitude should be the same. So 'if' the C engine has better performance down at sea-level than at 5,000ft, then I agree the climb rate should be slightly better at sea-level than at 5,000ft.

So what we need is a performance curve for the R-2800-57 "C" at different altitudes.


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## FLYBOYJ (Jun 14, 2005)

R-2800 INFO!

Here are the FAA Type Certificate Data Sheets (TCDS) for the civilian versions of the P&W R-2800. I think you might be able to extract some information from these:

http://www.airweb.faa.gov/Regulatory_and_Guidance_Library/rgMakeModel.nsf/0/137c165bea6c0fae8525670d0060671b/$FILE/E-264.pdf

http://www.airweb.faa.gov/Regulatory_and_Guidance_Library/rgMakeModel.nsf/0/28543f501b3e3cee8525670d0060471a/$FILE/E-231.pdf


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## DAVIDICUS (Jun 14, 2005)

I recall that the climb rates for the F6F and F4U are linear in inverse proportion to the increase in altitude and thus believe that the P-47 would follow in kind.

I guess we can argue about what "slightly better" means. 

As I stated earlier, "If the 3,500fpm figure at 5,000ft is correct, then the initial climb rate would be more like 3,600-3,650fpm (maybe as high as 3,700fpm) ..."

When I said "initial climb rate" above, I was indeed talking about the increase in climb rate that would be realized at sea level which is why I pointed out that the 3,500fpm initial climb rate would be incorrect as it is at 5,000ft. (Admittedly I could have been clearer.  ) 

When you first represented the FW-190-D-9's climb rate, you said," _The Fw-190D-9's climb rate was 3,660ft/min._" That's it. No altitude specified. Naturally, I assumed that that was the highest numerical climb rate figure attainable by the Focke Wulf and since we were comparing against the P-47N, wished to use the highest numerical climb rate figure achievable as well, which I just assumed to be sea level for both planes.

Since we were extrapolating from the "M" model data to better understand the "N" model data, the "at 5,000ft" issue was of concern for me.

At any rate, I am still hopeful that I can obtain that Republic Aviation documentation on the "M" and "N" performance.


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## FLYBOYJ (Jun 14, 2005)

DAVIDICUS said:


> I recall that the climb rates for the F6F and F4U are linear in inverse proportion to the increase in altitude and thus believe that the P-47 would follow in kind.



That's true for any recip aircraft.


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## DAVIDICUS (Jun 14, 2005)

Maybe you could help us (or at least me) with that task Flyboy. 

What are the fifferences between the "C" series 57 engine and the version of the engines presented in that data?

What conclusions do you infer from the presented data?


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## FLYBOYJ (Jun 14, 2005)

DAVIDICUS said:


> Maybe you could help us (or at least me) with that task Flyboy.
> 
> What are the fifferences between the "C" series 57 engine and the version of the engines presented in that data?
> 
> What conclusions do you infer from the presented data?



As you folks been discussing this, I've been trying to find that out. In those 2 links I gave you it gives a break down of the 2800 civilian versions, but the -97 is shown on the 2nd TCDS. Usually a letter after an engine model designator has to do with an accessory, like a generator or supercharger. The -57 seems to be exclusive to the P-47, the "C" might designate clockwise for either the engine or for an engine accessory.

I think when comparing the climb performance of different aircraft you have to factor in a given altitude, rpm, mp and fpm. As stated, climb performance is usually inversely linear (supercharging may change this a bit, but the bottom line eventually climb perfomance will go to hell at altitude, supercharger or not). Just to say that an aircraft will climb at 3700 fpm doesn't mean much unless you could determine at what altitude that's at. To make it more complicated, that climb performance will change as density altitude changes(altitude with temp factored in). Max climb performance should be shown starting at SL, 59F at 29.92hg - that's standard temp and pressure and usually performance charts are built around that base.


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## Soren (Jun 14, 2005)

I have this for the P-47D-35 which clearly states the "Max" initial climb rate:

P-47D-35-RA
Max. initial climb: 3,120 ft./min.

And it seems perfectly reasonable that the -47M was about 400fpm faster than the D-35.


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## FLYBOYJ (Jun 14, 2005)

I would assume that's at SL


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## DAVIDICUS (Jun 14, 2005)

Thanks Flyboy.

Let me ask for your input as you have some insight here. If we were to assume that the "M" model could climb at a rate of 3,500fpm at 5,000ft, what do you think the climb rate would be at sea level? 

I know that we are just estimating or even guesstimating.


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## FLYBOYJ (Jun 14, 2005)

I would "guess" about 3800 fpm, 59F, 29.92" I know its supposed to reach 15,000 in 4.9 seconds, so that would average about right!


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## Soren (Jun 14, 2005)

So we can all agree that the -47M wont reach 20,000ft in 4.75min now ?


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## DAVIDICUS (Jun 14, 2005)

Interesting.

The 4.9 min figure you are using as a backdrop is, I assume, the data I presented from: http://www.geocities.com/pentagon/quarters/9485/P-47M.html 

_Climb, at max. gross weight (including three 75 gallon drop tanks): *4.9 minutes to 15,000 feet* at 2,600 rpm (1700 hp). Reportedly, the "M" could reach 20,000 feet in 5.7 minutes at military power (2,100 hp @ 2,800 rpm). 20,000 feet in 4.75 minutes in WEP (2,800 hp @ 2,800 rpm). This is with full internal fuel and ammo. No external stores or drop tanks. In other words, normal load, clean configuration. _

That data has been the subject of the great debate (of epic proportions really  ) between Soren and myself on this thread. 

While we are on the subject, what do you think of the 4.75min to 20,000ft at WEP figure?

Does it appear plausible or does it strike you, as Soren would say, as "_an insane number_"?


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## Soren (Jun 14, 2005)

20,000ft in 4.75min by a P-47 !  Lets keep logical here...

You've already seen the power and wing-loading stats


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## FLYBOYJ (Jun 14, 2005)

I'd guess 20,000 by 5.5 min. Does anyone have a P-47M flight manual?


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## DAVIDICUS (Jun 14, 2005)

Thanks for your insight.

I may have a line on some Republic Aviation performance specs for the "M" and "N" model and will know more later this week.

The flight manual for the "N" model, however, can be downloaded at:

http://www.lanpartyworld.com/ww2/files/air-manuals/usaaf/


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## FLYBOYJ (Jun 14, 2005)

Thanks David, I'm downloading it!


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## Soren (Jun 14, 2005)

A sidenote: The P-47D-25 could reach 15,000 ft in 5 min 36 sec.


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## DAVIDICUS (Jun 14, 2005)

The only interesting information I saw was:

Maximum continuous (Normal rated power) 2,600rpm @ 43.5" 

Takeoff (military power) 2,800rpm @ 54" 

War emergency power 2,800rpm @ 72" 

The engine can be overspeeded to 3,120rpm for up to 30 seconds without damaging the engine. 

Weight: empty - 10,998lbs. Useful load varies from 2,824 to 10,199.9lbs. 

Wing Area: 322.2 sq. ft. giving a wing loading of approximately 43 lbs sq. ft. with normal gross weight 13,854lbs.


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## FLYBOYJ (Jun 14, 2005)

Again, thanks for the download David - 

In the -47N POH it states the "C" model 2800 has larger cooling fin area than the B which tell me the cylinder heads are different. From what I could see right now there are no performance charts, although those may be listed in another TO. I'm gonna print this puppy and read through it!


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## DerAdlerIstGelandet (Jun 15, 2005)

Good download very interesting.


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## Nonskimmer (Jun 15, 2005)

I too thank you for the link.


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## DerAdlerIstGelandet (Jun 15, 2005)

Where can you find more manuals online.


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## FLYBOYJ (Jun 15, 2005)

I went through the P-47N manual and there are no performance charts. This tells me that this data is either listed in another TO or you have calculate it using a performance calculator (it looks like a slide rule). This would be used when carrying a load (ordinance) to calculate climb, speed and fuel burn performance, especially important on hot days and when operating from high elevation airports.

In going back to those FAA documents I posted yesterday, I suspect that the data for the C17 engine is similar if not the same as the R-2800-57 based on the use of 100-130 fuel, which was the most common fuel used during the WW2 period.


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## DerAdlerIstGelandet (Jun 16, 2005)

FLYBOYJ said:


> (it looks like a slide rule). This would be used when carrying a load (ordinance) to calculate climb, speed and fuel burn performance, especially important on hot days and when operating from high elevation airports.



Is it like the Whiz Wheels that we use today. You can calculate lots of things with it including fuel burn rate which really beats doing it out by hand on a piece of paper, epecially as you said on hot days like today was.


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## mario29811 (Jan 24, 2016)

Do you people know the story of Robert S. Johnson, the first ace in World War 2 to surpass Eddie Rickenbacker's score of 26 kills? On June 26, 1943 when he was on an escort mission for B-17s, a group of FW-190s jumped the group and poured 21 20 millimeter cannon shells into his plane, causing the engine to catch on fire and the P-47 to spin out of control. It left Johnson partially blinded and burnt (and an easy target). He leveled off the plane and tried to bail, but his canopy was jammed. He noticed that the fire was out, and he maintained a heading for home. Shortly after, German Ace Egon Meyer (flying in a FW-190) spotted the damaged P-47 and opened fire. The P-47 was built so robustly that Meyer exhausted all of his ammunition attempting to shoot it down. When Johnston landed the plane, he started to count all the bullet holes in his airplane. When he reached 200 without moving around the airplane he gave up. Clearly, the P-47 is able to defeat the FW-190.


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## grampi (Jan 25, 2016)

DerAdlerIstGelandet said:


> Not to knock the P-47. She was a marvelous aircraft and to me one of the most underated allied aircraft (she is often overshadowed by the less capable P-51)



The less capable P-51? In what regard was the P-51 less capable?


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## Clayton Magnet (Jan 25, 2016)

You are asking him to clarify an 11 year old comment?


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## pbehn (Jan 25, 2016)

Clayton Magnet said:


> You are asking him to clarify an 11 year old comment?


The P51 has improved a lot in the last 11 years, since we fixed the oil leaks on Merlins.

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## DerAdlerIstGelandet (Jan 25, 2016)

grampi said:


> The less capable P-51? In what regard was the P-51 less capable?



Less capable is probably not the the best choice of words I could have used.

I however was referring to the fact that the P-47 was more multi-role than the P-51. Not only was it a good escort fighter, but was better suited than the P-51 for ground support roles for instance.

Most of all I was referring to the fact that I believe it is overshadowed by everyone doing the "Oh, Ah P-51...".

I understand you are a die hard P-51 "freak" (self proclaimed), but there where many great aircraft used in the second world war.

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## DerAdlerIstGelandet (Jan 27, 2016)

Well since 
G
 grampi
quoted a post of mine from a decade ago, I think the courtasy of a response to my response would be nice...

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## GregP (Jan 29, 2016)

My posts from when I was unemployed are best forgotten. 10 years ago? I'm sure most of us don't even think the same way as we did 10 years ago.

Well, maybe Bill Cosby ... nah, not even him. I bet he doesn't buy the same drugs today or use them the same way.

Could be wrong there ...

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## DerAdlerIstGelandet (Feb 22, 2016)

Bump...

Still waiting for 
G
 grampi
...


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## grampi (Feb 23, 2016)

DerAdlerIstGelandet said:


> Bump...
> 
> Still waiting for
> G
> ...



You're waiting for me to do what? I didn't see a question in your last post....I don't disagree with what you said about the P-47...


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## DerAdlerIstGelandet (Feb 23, 2016)

grampi said:


> You're waiting for me to do what? I didn't see a question in your last post....I don't disagree with what you said about the P-47...



Seemed like you did, since you felt the need to ask me about it. I answered, and was looking forward to a response.

It's called conversation. It's why the forum exists...

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## grampi (Feb 23, 2016)

DerAdlerIstGelandet said:


> Seemed like you did, since you felt the need to ask me about it. I answered, and was looking forward to a response.
> 
> It's called conversation. It's why the forum exists...



Fair enough. I agree the P-47 was better than the P-51 in certain respects. It was much tougher and could carry more, making it a much better choice for ground support roles. However, in air to air combat rolls the P-51 was superior...


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## DerAdlerIstGelandet (Feb 23, 2016)

grampi said:


> Fair enough. I agree the P-47 was better than the P-51 in certain respects. It was much tougher and could carry more, making it a much better choice for ground support roles. However, in air to air combat rolls the P-51 was superior...



At what altitude? Under what conditions. 

All of the top fighters had advantages and disadvantages over the others. That includes the P-51...

Some turned better. Some climbed better. Some rolled better. The pilot who knew how to use his aircrafts advantage over the other was going to win.

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## pbehn (Feb 23, 2016)

grampi said:


> Fair enough. I agree the P-47 was better than the P-51 in certain respects. It was much tougher and could carry more, making it a much better choice for ground support roles. However, in air to air combat rolls the P-51 was superior...


Over 15,000 feet the P 47 wins hands down until the P51B/C is introduced.


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## grampi (Feb 24, 2016)

DerAdlerIstGelandet said:


> At what altitude? Under what conditions.
> 
> All of the top fighters had advantages and disadvantages over the others. That includes the P-51...
> 
> Some turned better. Some climbed better. Some rolled better. The pilot who knew how to use his aircrafts advantage over the other was going to win.



If we're talking about the P-51B or later models, any altitude or conditions...I can't think of any situation where the 47 would outclimb or outturn the 51...the 47 may roll faster, and it dives faster (as It should, it was as heavy as a tank!)


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## grampi (Feb 24, 2016)

pbehn said:


> Over 15,000 feet the P 47 wins hands down until the P51B/C is introduced.



When I refer to the 51, I'm generally speaking about the Merlin powered ones...the "A" models were only good at low level and generally weren't intended to be used in air to air combat rolls....


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## pbehn (Feb 24, 2016)

grampi said:


> When I refer to the 51, I'm generally speaking about the Merlin powered ones...the "A" models were only good at low level and generally weren't intended to be used in air to air combat rolls....


I know, but the US and German bombing raids created a specific need, most air to air combat was conducted a short distance from where the plane took off and was at low level.


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## DerAdlerIstGelandet (Feb 24, 2016)

grampi said:


> If we're talking about the P-51B or later models, any altitude or conditions...I can't think of any situation where the 47 would outclimb or outturn the 51...the 47 may roll faster, and it dives faster (as It should, it was as heavy as a tank!)



In those regards you are probably correct, when I think about it...


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## GrauGeist (Feb 24, 2016)

grampi said:


> When I refer to the 51, I'm generally speaking about the Merlin powered ones...the "A" models were only good at low level and *generally weren't intended to be used in air to air combat rolls*....


The NA-73 was conceived and designed as a fighter (air to air combat) from the beginning.



grampi said:


> If we're talking about the P-51B or later models, any altitude or conditions...I can't think of any situation where the 47 would outclimb or outturn the 51...the 47 may roll faster, and it dives faster (as It should, it was as heavy as a tank!)


The P-47D-22 saw the introduction of the larger prop and put the P-47's RoC very close to that of the P-51D and that change also came as a huge surprise to the Luftwaffe, who, up to that point, were accustomed to climbing away from the P-47 in a fight.


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## grampi (Feb 24, 2016)

GrauGeist said:


> The NA-73 was conceived and designed as a fighter (air to air combat) from the beginning.
> 
> 
> The P-47D-22 saw the introduction of the larger prop and put the P-47's RoC very close to that of the P-51D and that change also came as a huge surprise to the Luftwaffe, who, up to that point, were accustomed to climbing away from the P-47 in a fight.



That's true about the original 51 being designed as an air to air fighter, but due to the Allison's poor high altitude performance, the "A" model was relegated to low level missions...


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## tomo pauk (Feb 24, 2016)

The low level mission and air-to-air fighting are not mutualy exclusive things 
Of course we know (do we?) that there was a P-51 before P-51A (and P-51A was better at altitude), along with A-36, indeed. And even A-36 was used as escort fighter.


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## Shortround6 (Feb 24, 2016)

And there were 620 Mustang Is before the first "P-51". two became XP-51s. 

Mustang I being a _better_ P-40 D-E/ Kittihawk. deliveries starting about the same month Aug-Sept of 1941 although Kittihawk production was much, much higher in early months. 
May 29th 1940 was when the British ordered the first 320 Mustang Is (off the drawing board) so a questions as to altitude performance or air to air combat intentions are pretty vague at this point. First Tomahawks (ex french contract) won't show up in England until Aug or Sept of 1940.


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## AlfaKiloSierra (Aug 18, 2019)

And in fact after that was introduced. The only altitude at which a 67" P-51B (which is faster than P-51D) can outrun a 70" P-47D is around the first stage supercharger crit alt of the P-51. See wwiiaircraftperformance.org, I compared the two before


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## AlfaKiloSierra (Aug 18, 2019)

Depends on the year. After July 24, 1944 no Fw 190 A could outrun, out-climb any P-47D except at very low altitude near 750m. The Fw 190 A-8 was cleared for operation at 1.65ata boost, 2700rpm in July 1944 [1]. As such, it can reach 651 kph at 5500m, and 591 kph at 750m, and significantly worse anywhere else [2]. The P-47 was cleared for operation at 70" boost, 2700rpm on June 24, 1944 [3]. As such, it reaches 430 mph at 18000ft, and 360 mph at 2460ft, and consistently everywhere else up to 23100ft [4]. Now, 360 mph is less than 591 kph, and 430 mph is much more than 651 kph. This is the speed. For climb, Fw 190 reaches 14m/s at 4900m, and 18m/s at sea level, and significantly worse elsewhere [1], and P-47 reaches 3200ft/min at 16000ft, and slightly less than 3200ft/min at sea level, and around that at all altitudes up to 18000ft [5]. 3200ft/min is significantly more than 14m/s, but less than 18m/s.

[1] http://www.wwiiaircraftperformance.org/fw190/td284.pdf Pg 3, Pg 5
[2] http://www.wwiiaircraftperformance.org/fw190/Fw_190_A-8_15-3-44.pdf Pg 7
[3] http://www.wwiiaircraftperformance.org/p-47/24june44-progress-report.pdf
[4] http://www.wwiiaircraftperformance.org/p-47/p47d-44-1-level.jpg
[5] http://www.wwiiaircraftperformance.org/p-47/p47d-44-1-climb.jpg

That's the case after July 1944. Before the P-47 had the 70" boost clearance, however, the situation is drastically different, especially with the P-47s that lacked the Hamilton Standard propeller, which the one tested above has. I don't have enough time to explain that though.

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## michael rauls (Aug 18, 2019)

I think that the answer to the title of the thread," which is better the FW190 or the P47" is that there is no right answer. As with so many comparisons of planes with drastically different qualities it depends on the mission and the oponent which is better.
In this comparison I would say each side had the plane that better suited there needs.

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## BiffF15 (Aug 19, 2019)

DerAdlerIstGelandet said:


> Yes the manufacturer and in some cases the military (normally after something bad happens) places limits on the aircrafts performance. The aircraft can perform better than these limits if need be but the limits are placed there to keep the pilot from doing something stupid.
> 
> Now in combat limits being exceeded is not uncommon. Many times the pilot exceeding the limits gets the kill.



Here is an example of exceeding limits to successfully get a kill...

Chasing a Mig, well above max tank jettison speed when he punches off his external wing tanks. Dash-1 (flight manual) warns this could happen. Notice missing portion of wing tip.

Squadron Commander: I heard you hurt one of my jets?

Pilot: Yes sir.

Squadron Commander: Did you get a kill?

Pilot: Yes sir.

Squadron Commander: Well done!

Cheers,
Biff

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## Greyman (Aug 21, 2019)

BiffF15 said:


> Here is an example of exceeding limits to successfully get a kill...



Not really analogous but reminded me of this anecdote:

_Sitting on the grass in the warm sunshine beside my aircraft waiting to be refueled, I found my attention drawn to a lone Spitfire making a circuit. As he turned into the wind, I noticed that his wheels weren't down. A red flare arched in the air from the Watch Office. Oblivious to the warning, the aircraft ground in on its belly in a cloud of dust. I recognized the Squadron letters to be the same as those of the Polish Squadron Leader and his two mates who, like me, were waiting to be refueled._

_As the pilot in the aircraft stood up in the cockpit, the three Poles ran to assist him. From a distance, the pilot appeared to be unhurt, and from the way he was moving his hands he was evidently recounting an engagement. His three Squadron mates gave a synchronous shout of triumph and threw up their hands. With his arm over the shoulder of the pilot the Squadron Leader led his men back to dispersal jabbering in Polish. As he passed me I asked:_

_'Was he shot up badly, Sir?'_​_'No,' he replied, in a tone as if I'd asked a stupid question._​_'Why didn't he put down his wheels?'_​_'Oh dat, he just forgot! What matter, he killed two German.'_​
_With a wide toothy grin and a convulsive grunt, he stomped his foot emphatically. I was very envious._

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## tomo pauk (Sep 8, 2019)

AlfaKiloSierra said:


> And in fact after that was introduced. The only altitude at which a 67" P-51B (which is faster than P-51D) can outrun a 70" P-47D is around the first stage supercharger crit alt of the P-51. See wwiiaircraftperformance.org, I compared the two before



Several things that need to be accounted for:
- Merlin Mustang will run at up to 75" Hg boost with 150 grade fuel; P-47D will run at up to 64-65" Hg with 130 grade fuel + ADI, it will need 150 grade fuel + ADI for 70" Hg boost
- when both aircraft were outfitted with racks, P-51D/K is no slower than P-51B/C, due to racks being of new, less draggy design 
- how fast was P-47D with wing racks?
- there is no such thing as 'the 1st stage supercharger crit alt', what can be is '1st speed S/C critical alt' - on 2-stage Merlins, both stages were always operating

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