# Hurricane IIc vs. B-17s B-24s



## Jerry W. Loper (May 7, 2010)

If the Hawker Hurricane IIc (armed with four 20-mm. cannon) had been a Luftwaffe instead of RAF fighter, how would it have done against USAAF B-17s and B-24s?


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## T Bolt (May 7, 2010)

I think it would have been more a question of how the Hurricane would have done against the escorting fighters as even with 10 fifty cal. brownings those bombers were pretty vulnerable to any fighter unless they had fighter escort.


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## timshatz (May 7, 2010)

Good point about the escort fighters. Wouldn't have lasted long against them. 

Hurricane 2 would have the firepower but not the speed or the climb to get ahead and above of bombers up that high. It could do it, but not as fast as the late war Luftwaffe fighters. Hurri was a prewar design and something of a throwback. The airframe did not lend itself to the development that the 109 (born about the same time) allowed. 

Given that, it would've done average against unescorted bombers, as long as it had a good vectoring. The cannons would've helped, effective against 4 engined bombers (it essentially the same armament as the FW190), But once the escorts show up, it has about the same chance of success as a 109E would've in the same situation. Not a lot.


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## T Bolt (May 7, 2010)

Probably the best way to use it would be the way it was used in the Battle of Britain. Let a fighter with better performance drive off the escort and have the Hurricanes go in after the bombers.


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## drgondog (May 7, 2010)

T Bolt said:


> Probably the best way to use it would be the way it was used in the Battle of Britain. Let a fighter with better performance drive off the escort and have the Hurricanes go in after the bombers.



The problem is that only the Me 262 and/or Ta 152 were 'superior' to the escorting Mustangs.

Prior to P-51 the Hurricane IIc with the Merlin geared for high blower in 22-25K would have been at least as effective as the Fw 190 (IMO) at 25,000 feet - maybe not as fast but still good performance at 25K when the Fw was falling off from 20+K.


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## Vincenzo (May 7, 2010)

drgondog said:


> The problem is that only the Me 262 and/or Ta 152 were 'superior' to the escorting Mustangs.
> 
> Prior to P-51 the Hurricane IIc with the Merlin geared for high blower in 22-25K would have been at least as effective as the Fw 190 (IMO) at 25,000 feet - maybe not as fast but still good performance at 25K when the Fw was falling off from 20+K.



afaik actual fth for hurricane IIc and 190 it's near the same


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## Colin1 (May 7, 2010)

The IIC's (clean aircraft, temperate) best altitude was around 20,000ft where it offered approx 340mph, so even if the bomber streams did oblige them and fly at that height, they'd still be no match for the escorts. At 25,000ft the IIC was barely managing 320mph; a fly-though of the bomber stream is going to be followed by a laboured catch-up phase, especially protracted if the bombers are B-24s. With a protracted catch-up being flown necessarily in a straight line at the P-51's best altitude, I wouldn't want to be a IIC pilot.

There is little performance margin allowing the IIC to go wheeling through the formation ad hoc, as soon as the IIC pilot takes evasive action against an escort, it's just ground he's got to make up again, assuming he's survived the escort. The IIC pilot will be struggling to avoid finding himself (quickly) at the rear of the bomber stream, trying to catch up again; so it's the bombers' guns to the fore (and considerably more than the IIC's Battle of Britain forebears had to endure) and the escorts' guns to the rear.

The IIC pilot's struggle to hold on to some/any kind of initiative vs the bombers is what will probably get him gunned down by the escorts.

I'll take the Fw190, the Hurricane's got too much up front that can get chewed, inline engine, ventral cooling and oil reservoir in the port wing leading edge; that upright windshield might take two strikes from a .50 cal if the pilot's having a good day, even if it is armoured.


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## pinsog (May 7, 2010)

The Zero had 2 20mm cannon, but B17's did quite well defending themselves from them. What would the top speed of the Hurricane been at B17 bombing altitude? If it didn't have a large speed advantage over the bombers, it could have found itself struggling to overtake them while being hammered by defensive fire. Didn't the 50 outrange the 20mm?


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## Glider (May 8, 2010)

I am sure that most will agree that without an escort the Hurricane IIc stands a good chance of doing significant damage as long as its vectored correctly, but once the escort turns up, then its day is done.

The same would apply to a number of RAF aircraft of 1943 Typhoons, Beaufighters, Spitfires Vc, Mossies you name it, they were all well armed and able to catch a cruising B17. When the escort turns up then its a different ball game.


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## riacrato (May 8, 2010)

pinsog said:


> The Zero had 2 20mm cannon, but B17's did quite well defending themselves from them. What would the top speed of the Hurricane been at B17 bombing altitude? If it didn't have a large speed advantage over the bombers, it could have found itself struggling to overtake them while being hammered by defensive fire. Didn't the 50 outrange the 20mm?



Type 99 has much lower MV than Hispano Mk.II. So the latter is more powerful and has more range.


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## pinsog (May 8, 2010)

What was the Hurricanes and B17's speed at 25 to 30 thousand feet? I think the one allied fighter that we should be glad the Germans didn't have would be the P47. Fast, high flying, very difficult to shoot down, even had good range, arm it with 4 20mm and a huge load of ammo, or 4 30mm and still a decent load of ammo. Dive through the formations, zoom climb, repeat. Scary to think about.


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## riacrato (May 8, 2010)

P-47 has sub-par climb, so no, it is not a good interceptor imo.


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## tomo pauk (May 8, 2010)

How about some numbers to back up that claim about P-47?


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## fastmongrel (May 8, 2010)

Depends which model of P 47 your talking about and whether it had the Curtiss paddle blade prop. Early versions of the Jug were not very good at climbing. Jug ace Don Blakeslee said about his early P47 C referring to the P-47's vaunted ability to dive on its prey, "_It ought to be able to dive. It certainly can't climb_." Blakeslee's early-model P-47C had not been fitted with the new paddle-blade propeller.

Luftwaffe pilots learnt not to try and manouver with the early Jug models but to climb hard and got a nasty shock when the 13 foot diameter Curtiss prop came into service


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## drgondog (May 8, 2010)

The pre 47D-10 also did not have WI although the -2 and -5 were retrofitted with WI along w/Paddle Prop.. still could not touch a 109 in any climb but a zoom climb (as an example). The 47C in all dash numbers were sluggish in climb.


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## Glider (May 8, 2010)

At the end of the day the P47 only had the 0.50 and this would have struggled against the US 4 engined bombers. All nations that faced them upgunned their fighters to have cannons.


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## pinsog (May 8, 2010)

Which model P47? Use the exact same timeline as the US P47 with the same upgrades. Can't climb? Germans had plenty of time to climb to altitude since they had radar to warn them well in advance. Once engaged, dive on bombers, make a pass, blow through, full power convert speed back into altitude in a zoom climb. Repeat. When the paddle prop comes along, the climbing problem is resolved, P47 becomes even more dangerous. P47 had longer range than 109 and 190, it wouldn't have been as critical to know the exact target the allies were going to hit as it was with the 109 and 190.


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## pinsog (May 8, 2010)

We are assuming the Germans had developed the P47 so it would have had cannon. Yes the 50 would have struggled against 4 engines heavies


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## Glider (May 8, 2010)

Interesting. I thought we were looking at how the Hurricane a well armed but obsolete fighter would manage against the B17 and B24.
Now we are looking at the germans developing the P47 which they didn't do and arming it with guns it never had against the B17 and B24 which were on the same side ie American.


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## tomo pauk (May 8, 2010)

While I'll agree that P-47s (before water injection paddle blade prop were introduced) were not such good climbers, when compared with 109, P-51 Spit, that was not rendering them being inefficient interceptors.

Sorry for helping skewing the thread :\


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## pinsog (May 8, 2010)

Sorry GLIDER, we can move back to reality, a British plane, flown by Germans, shooting down Americans.


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## Colin1 (May 8, 2010)

pinsog said:


> Sorry GLIDER, we can move back to reality, a British plane, flown by Germans, shooting down Americans.


Well no
but we can move back to the OP's what-if, which was as you say


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## drgondog (May 8, 2010)

Glider said:


> At the end of the day the P47 only had the 0.50 and this would have struggled against the US 4 engined bombers. All nations that faced them upgunned their fighters to have cannons.



I can not think of any reason why the 20mm could not be designed into a P-47 wing, each one replacing 2 x .50s..


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## pinsog (May 8, 2010)

Anyone have a guess how many rounds per gun you could carry with 2 20mm in each P47 wing? I would think it would be ALOT.

No one ever answered how fast a Hurricane and B17 are at 25 to 30 thousand feet. Anyone know?


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## Vincenzo (May 8, 2010)

pinsog said:


> Anyone have a guess how many rounds per gun you could carry with 2 20mm in each P47 wing? I would think it would be ALOT.
> 
> No one ever answered how fast a Hurricane and B17 are at 25 to 30 thousand feet. Anyone know?



around 315 and 295 mph

for clear i'm talking of hurry iic to 25 30k


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## Colin1 (May 8, 2010)

pinsog said:


> No-one ever answered how fast a Hurricane and B-17 are at 25 to 30 thousand feet


I did in post #7 but I interpreted some figures wrongly, my apologies

Hurricane IIC (clean aircraft, temperate)
330mph @ 18,000ft 
326mph @ 20,000ft 
320mph @ 25,000ft 
300mph @ 30,000ft 

The Hawker Hurricane by Francis K Mason ARAeS
The graph itself is not fine graticule so figures are a good approximation at best

I don't have any figures for the B-17 but a quick scan on the 'net revealed

274mph @ 25,000ft with a 6,000lb bombload and an AUW of 64,200lbs
278mph @ 25,000ft with a 6,000lb bombload and an AUW of 57,700lbs

http://www.zenoswarbirdvideos.com/Images/B-17/17TRC.pdf
http://www.zenoswarbirdvideos.com/Images/B-17/17FOIC.pdf

Unfortunately, one's in Indicated Airspeed and the other's in Average True Airspeed, not sure what the difference is.


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## pinsog (May 8, 2010)

I don't think a 300 mph fighter could effectively intercept a heavily armed 278 mph aircraft. If you make one pass from the front your done, you'll never catch them again. You come creeping up behind them with a 20 mph advantage, I think you would get your tail shot off.


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## Glider (May 8, 2010)

pinsog said:


> I don't think a 300 mph fighter could effectively intercept a heavily armed 278 mph aircraft. If you make one pass from the front your done, you'll never catch them again. You come creeping up behind them with a 20 mph advantage, I think you would get your tail shot off.



I would agree with this but the B17 would be at cruising speed which would be a lot closer to 200mph giving the Hurricane sufficient advantage for multiple attacks.


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## riacrato (May 9, 2010)

> Can't climb? Germans had plenty of time to climb to altitude since they had radar to warn them well in advance. Once engaged, dive on bombers, make a pass, blow through, full power convert speed back into altitude in a zoom climb.


Bf 109s were often still climbing when intercepting the bombers. Depending on situation, location and skill of ground crews. You'd only make that worse with a P-47.

When is P-47 with WI and paddle bladed propeller available in any numbers? And how big is the increase in roc really?


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## timshatz (May 9, 2010)

pinsog said:


> I don't think a 300 mph fighter could effectively intercept a heavily armed 278 mph aircraft. If you make one pass from the front your done, you'll never catch them again. You come creeping up behind them with a 20 mph advantage, I think you would get your tail shot off.



Gotta keep in mind that the Top Speed and the Cruise Speed are two different things. The B17 cruised around 150Mph. Top speed in a formation would be about that. You need to keep the formation intact. To do that, You need to keep the speed down.

As for the Hurricane, the same thing applies but not to as great an extent. The numbers north of 300Mph are for a new airplane, running solo. Put a formation of 4 or 12 together and the speed drops quickly. Think in terms of a formation speed in the 230 to250Mph range for the Hurricanes. Maybe even 200mph as the formation gets over 12 airplanes. 

Once the Hurricanes attack, then the individual airplanes speed becomes more important. Most likely, the Hurricanes will be attacking in groups or singly. As such, the top speed of each airplane, on full power but not with boost, comes into play. And that is very variable. An airplane 6 months old that's been flown a lot might have a top speed of only 275mph while one that came out of the factory only two days before may make close to 320. 

Had the experience myself of flying two different airplanes of the same exact type and had one fly 10-15% slower than the other. Why? Engine wear putting out lower horsepower than the other, rigging of the flight controls, wear and tear on the airframe will screw with the performance in a big way. Especially top speed and climb. Those two are easily affected by changes in the airplane. 

Just a little food for thought.


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## Timppa (May 9, 2010)

drgondog said:


> The pre 47D-10 also did not have WI although the -2 and -5 were retrofitted with WI along w/Paddle Prop.. still could not touch a 109 in any climb but a zoom climb (as an example).



Gabreski (in his bio) disagrees.
"Previously, we found the fastest way to gain altitude in combat was to dive and zoom, and the German pilots were well aware of it. Now we could pull the P-47's nose up and keep on going after them."
The US term for water injection was ADI ("Anti-Detonant Injection")


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## drgondog (May 9, 2010)

Timppa said:


> Gabreski (in his bio) disagrees.
> "Previously, we found the fastest way to gain altitude in combat was to dive and zoom, and the German pilots were well aware of it. Now we could pull the P-47's nose up and keep on going after them."
> The US term for water injection was ADI ("Anti-Detonant Injection")



Timppa - USAAF test pilots did not achieve superior rates of climb in the P47D-10 over a P-51 or a P-38. 

Both Gabreski and Johnson were very enthusiastic about its 'new' ROC but, as Johnson claimed, a 47D outclimbing a Spit in his book was also stretching the realities a tad. 

In addition to the above points, Gabreski didn't identify the German a/c that the 47D could continue pursuing in a climb - but I suspect that it was a 190?

I have sat and listened through many many discussions between air force aces that fought in MTO and ETO and there was never one statement that either a P-47 or a Mustang could outclimb a 109. Ditto for outclimbing or out turning a contemporary Spit

Never.


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## pinsog (May 9, 2010)

The reason German aircraft were sometimes still climbing when they were meeting the bombers was because they were so short ranged that they had to wait until the last possible minute to launch them or they might run out of fuel. A P47 employed by Germany would have plenty of fuel to launch before the bombers arrived and climb above them and loiter for a bit. In fact, if Germany had P47's, couldn't they have brought more units in from farther away to help intercept bomber formations? The Allies would often zigzag bomber formations so the Germans would launch fighters from the wrong area and then turn away so those fighters would land due to low fuel and then turn the formation back again, catching German fighters in that area on the ground refueling. That wouldn't have been an issue if the Germans would have had longer legged fighters.


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## Glider (May 9, 2010)

timshatz said:


> Gotta keep in mind that the Top Speed and the Cruise Speed are two different things. The B17 cruised around 150Mph. Top speed in a formation would be about that. You need to keep the formation intact. To do that, You need to keep the speed down.
> 
> As for the Hurricane, the same thing applies but not to as great an extent. The numbers north of 300Mph are for a new airplane, running solo. Put a formation of 4 or 12 together and the speed drops quickly. Think in terms of a formation speed in the 230 to250Mph range for the Hurricanes. Maybe even 200mph as the formation gets over 12 airplanes.
> 
> ...



All good and valid points and at the end of the day the Hurricane will still have a 100+ mph advantage over the cruising B17/B24.

More than sufficient for the task in hand.


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## Vincenzo (May 9, 2010)

timshatz said:


> The B17 cruised around 150Mph..



afaik this cruising speed it's IAS and not TAS


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## pinsog (May 9, 2010)

Please define difference between IAS and TAS.


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## Shortround6 (May 9, 2010)

pinsog said:


> Please define difference between IAS and TAS.



See: True Airspeed Calculator


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## timmo (May 9, 2010)

Nobody seems to have mentioned the ability of the pilot to shoot to kill, no matter what weapon?

I certainly couldn't!!

= Tim


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## CharlesBronson (May 9, 2010)

Not well, too slow rate of climb.


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## Colin1 (May 9, 2010)

timmo said:


> Nobody seems to have mentioned the ability of the pilot to shoot to kill, no matter what weapon?
> 
> I certainly couldn't!!
> 
> = Tim


Tim
did you fly the later versions of the Hurricane? How rapidly did the Hurricane airframe bleed off energy in turns?


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## drgondog (May 9, 2010)

Vincenzo said:


> afaik this cruising speed it's IAS and not TAS



absolutely correct - at 25K that would be 200-210 TAS. When a B-17 unloaded, it could fly faster home bound.


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## riacrato (May 9, 2010)

pinsog said:


> The reason German aircraft were sometimes still climbing when they were meeting the bombers was because they were so short ranged that they had to wait until the last possible minute to launch them or they might run out of fuel.



Never heard that reasoning anywhere before. Your source for that? Max. endurance of the Bf 109 G was over 3 hours. At cruise speed around 1.5 hours iirc. Surely not the best in this regard, but easily enough to time to climb to altitude and linger for quite some time.

Depending on situation vectoring in the defensive forces ranged from good to very poor. Sometimes LW units would need to scramble simply because Allied air forces were detected too late or the true target was not known.


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## timshatz (May 9, 2010)

Vincenzo said:


> afaik this cruising speed it's IAS and not TAS



Agreed Vincenzo, but the affect is the same with the Hurricane. So, if the TAS for the B17 is 150 and the Hurris is running at 250, they both have the correction factor in their speeds. Kinda like the Altimeter being set without taking the local conditions (hence the reason why the tower always tells you the altimeter setting, so everyone has the same correction in).

In short, everybody is playing with the same localy based correction.


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## timshatz (May 9, 2010)

timmo said:


> Nobody seems to have mentioned the ability of the pilot to shoot to kill, no matter what weapon?
> 
> I certainly couldn't!!
> 
> = Tim



A really, really good point.


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## timshatz (May 9, 2010)

Glider said:


> All good and valid points and at the end of the day the Hurricane will still have a 100+ mph advantage over the cruising B17/B24.
> 
> More than sufficient for the task in hand.



Yeah, that should do it. Goes back to the ability to get ahead and attack from the most vulnerable spot on both 4 engined bombers. Need to climb and go fast enough. Climb, your speed goes done. Level full power, you are not getting up to the bomber's level. Think the Hurricane would've been up against it to get ahead and above the formation. But, it has the speed. Maybe they adapt the tactics to not go below the formation after attacking.

Maybe the Luftwaffe did that anyway. 

I think Timmo had the best point out there that nobody seems to bother with. That a lot of people just couldn't do it when it came down to attacking another airplane, regardless of the circumstances. Most people don't have the instinct to kill that is neccesary to attack another airplane, regardless of the aircraft performance. It's not an easy thing to develop. Most military training is geared to supress that desire not to hurt somebody else. Only 10%, roughly, are going to press in for the kill. Most are going to pull off early, evade or let themselves be pulled off to the side in a distraction. And a head on attack, on a heavy bomber formation, is the definition of hairy. Upwards of 70 machine guns firing tracer at you, man, that has got to make you flinch. 

I don't know specifically where to go with it, but it seems it should be a factor to consider. If you have an airplane that is not good at getting ahead of the formation, and you donn't want to get ahead of the formation you should attack....


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## pinsog (May 9, 2010)

TIMSHATZ, I never heard of pilots having trouble shooting at each other unless they were just afraid of getting killed themselves. Everyone has heard of soldiers having trouble pulling the trigger, but that was a human being in the sights of a rifle, not a piece of machinery surrounding a pilot. I have always read that pilots detatched themselves from what was happening and convinced themselves that they were shooting at machinery and not trying to kill the pilot, except of course those that hated the enemy badly enough that they WERE trying to kill the other pilot.


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## Vincenzo (May 10, 2010)

timshatz said:


> Agreed Vincenzo, but the affect is the same with the Hurricane. So, if the TAS for the B17 is 150 and the Hurris is running at 250, they both have the correction factor in their speeds. Kinda like the Altimeter being set without taking the local conditions (hence the reason why the tower always tells you the altimeter setting, so everyone has the same correction in).
> 
> In short, everybody is playing with the same localy based correction.



no the hurry can't go 250 mph ias at 25k'


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## timshatz (May 10, 2010)

pinsog said:


> TIMSHATZ, I never heard of pilots having trouble shooting at each other unless they were just afraid of getting killed themselves. Everyone has heard of soldiers having trouble pulling the trigger, but that was a human being in the sights of a rifle, not a piece of machinery surrounding a pilot. I have always read that pilots detatched themselves from what was happening and convinced themselves that they were shooting at machinery and not trying to kill the pilot, except of course those that hated the enemy badly enough that they WERE trying to kill the other pilot.



There is a good segment in a show called "Piece of Cake" about British fighter pilots during the Battle of Britian that pretty much covers it. The scene is where the Squadron Leader (a guy named Fanny, believe it or not) is talking to his intelliegence officer and one other guy about the pilots in the squadron. He says, and I'm going on memory but it was a well done scene so I kinda remember it, "We've got two good pilots, 3-4 average pilots and the rest aren't worth anything". The scene is composed right after gun camera shows one of the pilots in the squadron shooting down another RAF fighter (thought it was an ME109).

Only 5% of fighter pilots become aces. There are a multitude of reasons why. First, opportunity. A lot of pilots will fly a full tour without ever seeing an enemy aircraft. Second, (and this is a very rough list) determination. A pilot who sets out to shoot down another airplane is taking a pretty good risk that he himself will be shotdown himself. Most guys get shot down without knowing anyone else is there. There are a lot of reasons for it but the two most common are having a low SA (situational awareness, or not knowing what is going on and who's around) and they are committed to an attack when they themselves are attacked. The last point is very important as the determination to make a kill is difference between an ace and a good pilot. When you make an attack on somebody, you know the odds of getting shot down are increasing as you make your run. So, the old rule of get in, hit and get out is the standard. 

A lot of pilots don't want to take that risk. 99% of the time, if you see the guy making a run on you, you can avoid him fairly easily. Most guys work from that perspective and spend as much time as possible covering their own and their buddies ass. Dogfights, while somewhat famous, are relatively rare. If one or the other guy doesn't want to fight and they both see each other from far enough away, there won't be a long fight. The one who doesn't want to take the chance will clear out. It's not cowardice, it's smart. It's the way to survive. And plenty of people did it and nobody though any less of them for it. For every ace, there have to be a couple of guys up there watching their tails. 

Kind of a long and meandering post but I hope I covered some of the perspective.


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## renrich (May 10, 2010)

Tim, I think your post makes some good points. Two other factors which fit in with what you said is that most successful fighter pilots had very good eyesight and many of them were very good gunners. An example was Joe Foss who had a lot of experience hunting, especially wing shooting. Of course the good eyesight contributes to the good SA.


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## timshatz (May 10, 2010)

renrich said:


> Tim, I think your post makes some good points. Two other factors which fit in with what you said is that most successful fighter pilots had very good eyesight and many of them were very good gunners. An example was Joe Foss who had a lot of experience hunting, especially wing shooting. Of course the good eyesight contributes to the good SA.



Thanks Ren. Hope it was helpful. 

Good gunners and great eyesight are a must. Well, the great eyesight anyway. Hartman used to say the guy who sees the other first has won half the battle. Very true. And gunnery was hugely important. As the old saying goes, good flying never shot anyone down. You could be a great pilot but not get anything done while an average pilot who was a very good shot could produce. And if all else fails, do what Zempke used to say and get so close you can't miss. Then, there isn't any question of gunnery. 

An interesting point that I read about from the Pacific war. I think it was an Intelligence Officer in one of the P38 groups who looked at the film from the gun cameras off all the pilots. He found that the aces tended to shoot at other airplanes about 2x more often than other pilots. Also, they tended to shoot in all sorts of odd attitudes (upside down, turning, ect) whiereas the average pilot was usually pretty close to straight and level. 

Probably somewhere in the reasoning that basketball players have of 100% of the shots you don't take, won't go in.


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## pinsog (May 10, 2010)

TIMSHATZ, I agree with your whole paragraph. Everything you put in there I have read somewhere at sometime. One other thing that I have read, supposedly most WW2 American aces were farm boys, country boys, rural raised young men. Evidently they had learned wing shooting and shooting small game and deer on the run so they already understood the concept of leading the target.


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## Timppa (May 10, 2010)

drgondog said:


> Timppa - USAAF test pilots did not achieve superior rates of climb in the P47D-10 over a P-51 or a P-38.



Hmm.. I did not make any claim about the climbrates between American planes (let alone Spitfires)
But since you brought it up: P-47D w/ paddle blade propeller and ADI outclimbs P-51D above 25,000ft.
Also the climb rate is at least equal, if not better, than Bf109-G6 ( again above 25,000ft).
Bf109-K4 climbs better than P-47D through the whole height range. But compared to P-47M it is again inferior above 25,000ft.


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## timshatz (May 10, 2010)

pinsog said:


> TIMSHATZ, I agree with your whole paragraph. Everything you put in there I have read somewhere at sometime. One other thing that I have read, supposedly most WW2 American aces were farm boys, country boys, rural raised young men. Evidently they had learned wing shooting and shooting small game and deer on the run so they already understood the concept of leading the target.



Agreed wholeheartedly. Familiarity with guns is very useful. Helps you think the right way to take the shot. Further, familiarity with hunting is very important. Stalking, shooting, angles, all that stuff comes into play when hunting. Getting the right shot at the right time. Also, something that doesn't come up, is the familarity with making a kill shot that hunting alows. First time I shot at a buck, I got a serious dose of buck fever. Couldn't believe it. My mind was clear but all the sudden I started to shake. Very, very odd, caught me totally offguard. Getting that first one is probably as important for fighter pilots, if not more. After that, you probably have that "I can do that" momment. 

Breaking through a mental wall, so to speak.


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## renrich (May 10, 2010)

I do think I read that Erich Hartmann was not a particularly good gunner but that he waited until the target filled his windscreen until opening fire. Undoubtedly he had superior eyesight.


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## drgondog (May 10, 2010)

Timppa said:


> Hmm.. I did not make any claim about the climbrates between American planes.
> But since you brought it up: P-47D w/ paddle blade propeller and ADI outclimbs P-51D above 25,000ft.
> Also the climb rate is at least equal, if not better, than Bf109-G6 ( again above 25,000ft).
> Bf109-K4 climbs better than P-47D through the whole height range. But compared to P-47M it is again inferior above 25,000ft.




Nearly true Timppa. Both the 51B/C and D with 1650-7 outclimbed the P-47D-10 and subsequent variants of the D up to ~ 30,000 feet - and combat between German fighters and most USAAF fighters was from 25,000 feet to the deck.. where the P-47 increasingly was at a disadvantage in both the horizontal and vertical with the contemporary German fighters as the altitude decreased after the initial contact.. as well as the P-51B/C and D.

P-47 Performance Tests
P-51 Mustang Performance

I need to check but IIRC the 109G6-A/S outclimbed both the P-51 and P-47 at 30K.

The Luftwaffe (as well as all of Germany) never saw more than 60 P-47M's on any given day after Christmas 1944 as only the 56th FG had them. Further, the wiring harness issues with the M largely rendered it ineffective compared to its target performance until March 1945. So what might the point be to bring up the P-47M?

The point of my challenge to the Gabreski recollection (and Robert Johnson's) is that while they marvelled at the performance boost of the paddle prop ad WI - that combination did not close the gap enough between the P-47D and the 109G to match it in climb - I should have stipulated that was true only for the first 30,000 feet above sea level to make my statement clearer.

The P-47D was an excellent fighter but, until the M, it was never a world beater in the positive vertical at any useful combat altitudes.


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## drgondog (May 10, 2010)

timshatz said:


> There is a good segment in a show called "Piece of Cake" about British fighter pilots during the Battle of Britian that pretty much covers it. The scene is where the Squadron Leader (a guy named Fanny, believe it or not) is talking to his intelliegence officer and one other guy about the pilots in the squadron. He says, and I'm going on memory but it was a well done scene so I kinda remember it, "We've got two good pilots, 3-4 average pilots and the rest aren't worth anything". The scene is composed right after gun camera shows one of the pilots in the squadron shooting down another RAF fighter (thought it was an ME109).
> 
> Only 5% of fighter pilots become aces. There are a multitude of reasons why. First, opportunity. A lot of pilots will fly a full tour without ever seeing an enemy aircraft. Second, (and this is a very rough list) determination. A pilot who sets out to shoot down another airplane is taking a pretty good risk that he himself will be shotdown himself. Most guys get shot down without knowing anyone else is there. There are a lot of reasons for it but the two most common are having a low SA (situational awareness, or not knowing what is going on and who's around) and they are committed to an attack when they themselves are attacked. The last point is very important as the determination to make a kill is difference between an ace and a good pilot. When you make an attack on somebody, you know the odds of getting shot down are increasing as you make your run. So, the old rule of get in, hit and get out is the standard.
> 
> ...



I was at a Fighter Aces reunion in Dalls (~1967) with my father when WFAA (Channel 8) reporter questioned several aces including Rall and Olds and Foss and Yeager, etc, including my father - all of them gave the stock answers to 'what makes a fighter pilot'?? Except for one ace, Billy Hovde, all of them gave the same general answers. "know the capability of your airplane as well as the enemy a/c, have situational awareness, close until you are in range to shoot, keep your airspeed up, be aggressive,etc, etc"

When the reporter stuck his mic in front of Hovde, (who was feeling little pain), he thought for a couple of seconds and said'..

Well, the first god_______ed thing you have to have is a reminder that no one lives forever"

Hovde took 12 ships of the 358FS/355FG into a gaggle of 75+ Fw 190s with some escorting 109s on December 5, 1944 and personally shot down 5, shared a sixth while the squadron nailed 12 and completely broke up the attack over Berlin - with no losses. Distinguished Service Cross. He walked his talk.


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## riacrato (May 10, 2010)

drgondog said:


> Nearly true Timppa. Both the 51B/C and D with 1650-7 outclimbed the P-47D-10 and subsequent variants of the D up to ~ 30,000 feet - and combat between German fighters and most USAAF fighters was from 25,000 feet to the deck.. where the P-47 increasingly was at a disadvantage in both the horizontal and vertical with the contemporary German fighters as the altitude decreased after the initial contact.. as well as the P-51B/C and D.
> 
> P-47 Performance Tests
> P-51 Mustang Performance
> ...


The trials conducted with the G-6/U2 by the RAF performed concluded the Bf 109 was slightly superior in climb to the Mustang III with 18 lbs boost until around 20,000 feet. So that is in line with your observations.

I would be surprised if any contemporary P-47 was a faster climber than a Mustang III. Or that the advantages probably both held at anything beyond say 22,000 over a Bf 109 G would turn into a shorter time to climb to that altitude, which is what I was getting at. 

And that is a Bf 109 G version with two underwing gondolas, so a version arguably already at least as good at bomber killing as the standard P-47. A later G with Mk 108 should be a bit faster in the vertical too.

As noone answered my question I searched a bit and found the Curtiss paddle blade propeller and WI to be used on most P-47s starting November-December '43. Right?


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## Vincenzo (May 10, 2010)

riacrato said:


> ''
> 
> As noone answered my question I searched a bit and found the Curtiss paddle blade propeller and WI to be used on most P-47s starting November-December '43. Right?



for the WI i'm agree for the paddle blade propeller i remember late


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## DAVIDICUS (May 10, 2010)

Paddle Blade, Water Injection and 150 octane fuel:

P 47D Performance Test

Looks like about 2,375fpm at 25,000ft and 1,650fpm at 30,000ft.


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## timshatz (May 10, 2010)

drgondog said:


> I was at a Fighter Aces reunion in Dalls (~1967) with my father when WFAA (Channel 8) reporter questioned several aces including Rall and Olds and Foss and Yeager, etc, including my father - all of them gave the stock answers to 'what makes a fighter pilot'?? Except for one ace, Billy Hovde, all of them gave the same general answers. "know the capability of your airplane as well as the enemy a/c, have situational awareness, close until you are in range to shoot, keep your airspeed up, be aggressive,etc, etc"
> 
> When the reporter stuck his mic in front of Hovde, (who was feeling little pain), he thought for a couple of seconds and said'..
> 
> ...



OUTSTANDING! Great post.


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## pinsog (May 10, 2010)

TIMSHATZ, got a good laugh at your buck fever tale. I hadn't had it in years until last year when I saw a HUGE buck in Kansas while rifle hunting, I started shaking so bad I couldn't have shot my own foot! Felt good after it was over. And to think, we were in no danger at all. Imagine some poor fighter pilot with barely enough training to fly the bucket he's in, probably already puked a time or two that morning, running into a flight of enemy aircraft flown by veterans. 
It's a wonder 
1. they could get anyone to do it
2. anyone would try again after the 1st time
3. anybody ever actually got shot down
I bet alot of those "dogfights" looked like those toughman competitions where both fighters are so afraid of getting hit that they dont get close enough to ever connect with a punch, they just stand out there out of range and punch each others gloves.
Then of course you get the 1% that are professionals and they are the ones that end up with all those kids painted on the side of there cockpits.


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## timshatz (May 10, 2010)

Yeah Pin, that probably happened a lot more than people think. Two sides show up, one side really doesn't want to bother with a brawl (for whatever reason) and nothing happens. Thinking situations like that probably were more common during the British offensive into France in 1941/42 where the Luftwaffe didn't HAVE to fight. Could pick it's place and time to go at it. 

I remember reading "No Parachute" by A.G. Lee. It was a WW1 fighter book but he talks about the same thing happening. A bunch of Albatross show up, both they (in Sopwith Pups) and the Albatross manuver to get in the best position but neither likes the spot there are in versus the other side. Finally, one side (usually the Germans as they had fewer aircraft and had to pick their fights better) would turn around and dive for home leaving the other side stoodging around with nobody to play with. 

I guess it wasn't all blood and guts all the time.


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## renrich (May 10, 2010)

One man's account of P47 prowess in ACM and this was undoubtedly not at the P47s best altitude. Ralph Linnekin, "80 knots To Mach 2" " That useful altitude reference is in honor of the P47, which is difficult to categorise. The N version is credited with something on the order of 469 mph, but at 32000 feet. What reciprocating engine airplanes actually fought at 32000 feet? It may be useful to fly that high, but at what cost. The P47 was a very good airplane with a fine combat record. It was not, however lauded as a sterling performer. I contrast that high-altitude performance with contemporary reports that some versions of the P47 were dogs below 10000 feet. The airplane had a huge turbo supercharger that, by a combination of drag and mechanical power bleed off must have caused a substantial performance degradation at other than optimum altitudes. I know a couple of people in a Bearcat squadron who had an inadvertant encounter with four late model P47s one day in 1947. ( Inadvertant, hell. The Bearcats jumped them. What did you expect. The P47s were there.) It was no contest- partly because the Bearcat, below 10000 feet, could do absolutely everything better than anything else with a propeller and at low altitudes could out accelerate most contemporary jets. Nonetheless, our guys said that AD Skyraiders and even SB2C Helldivers flown aggressively had at other times given them as much trouble as the P47s."


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## Nikademus (May 11, 2010)

renrich said:


> The N version is credited with something on the order of 469 mph, but at 32000 feet. What reciprocating engine airplanes actually fought at 32000 feet? It may be useful to fly that high, but at what cost. "



A good point.


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## Timppa (May 11, 2010)

drgondog said:


> Nearly true Timppa. Both the 51B/C and D with 1650-7 outclimbed the P-47D-10 and subsequent variants of the D up to ~ 30,000 feet - and combat between German fighters and most USAAF fighters was from 25,000 feet to the deck.. where the P-47 increasingly was at a disadvantage in both the horizontal and vertical with the contemporary German fighters as the altitude decreased after the initial contact.. as well as the P-51B/C and D.
> 
> P-47 Performance Tests
> P-51 Mustang Performance



Nearly true drgondog
I think the above sources you gave show that P-47D beats P-51D (V-1650-7) above 25,000ft.
I even checked a couple of sim charts. Any difference between P-47D (again w/ high activity prop and ADI) and German fighters was not big even at lower altitudes. (considering models Bf109-G6 and Fw190A-5/8, early 1944 timeframe).
Gabreski gave one account where he outclimbed 190's from practically stall speed.


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## T Bolt (May 11, 2010)

renrich said:


> One man's account of P47 prowess in ACM and this was undoubtedly not at the P47s best altitude. Ralph Linnekin, "80 knots To Mach 2" " That useful altitude reference is in honor of the P47, which is difficult to categorise. The N version is credited with something on the order of 469 mph, but at 32000 feet. What reciprocating engine airplanes actually fought at 32000 feet? It may be useful to fly that high, but at what cost. The P47 was a very good airplane with a fine combat record. It was not, however lauded as a sterling performer. I contrast that high-altitude performance with contemporary reports that some versions of the P47 were dogs below 10000 feet. The airplane had a huge turbo supercharger that, by a combination of drag and mechanical power bleed off must have caused a substantial performance degradation at other than optimum altitudes. I know a couple of people in a Bearcat squadron who had an inadvertant encounter with four late model P47s one day in 1947. ( Inadvertant, hell. The Bearcats jumped them. What did you expect. The P47s were there.) It was no contest- partly because the Bearcat, below 10000 feet, could do absolutely everything better than anything else with a propeller and at low altitudes could out accelerate most contemporary jets. Nonetheless, our guys said that AD Skyraiders and even SB2C Helldivers flown aggressively had at other times given them as much trouble as the P47s."



I don’t think it’s fair to compare the P-47 to the F8F. The Thunderbolt was a very large high altitude turbo supercharged fighter which first flew in 1940. The Bearcat was a small fighter –the size of a Wildcat- with the same engine as the Thunderbolt. Of course it would out fly a Thunder bolt at low altitude. The P-47 was out of its element and the Bearcat was in its, as a sprinter meant to catch and shoot down Kamikazes. The F8F didn’t see service until 1945. It was part of that next generation of piston engine fighters that were made essentially useless when still new due to the advent of jets.


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## drgondog (May 11, 2010)

Timppa said:


> Nearly true drgondog
> I think the above sources you gave show that P-47D beats P-51D (V-1650-7) above 25,000ft.
> I even checked a couple of sim charts. Any difference between P-47D (again w/ high activity prop and ADI) and German fighters was not big even at lower altitudes. (considering models Bf109-G6 and Fw190A-5/8, early 1944 timeframe).
> Gabreski gave one account where he outclimbed 190's from practically stall speed.



P 51D Performance Test
Table C. gives 30,000 ROC for P-51D-15 = 1700fpm, 2400fpm @ 25K using regular 130 octane. 
3000 RPM at 67"

http://www.wwiiaircraftperformance.org/p-47/p47d-44-1-climb.jpg for July 1944 tests w/44-1 fuel
Table 7. ROC for P47D-10 = 1650fpm @ 30K, 2360fpm @ 25K using 44-1 fuel
2700 RPM at 70"

I haven't been able to dig up comparable 51D performance for 3000 RPM and 72" boost but it will clearly show better performance than the above P-47D w/150 octane.

I'll have to look at Gabby's anecdote fro context - outclimbing a 190 at 25K is different from 10K


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## tomo pauk (May 11, 2010)

renrich said:


> ...
> The airplane [P-47]had a huge turbo supercharger that, by a combination of drag and mechanical power bleed off must have caused a substantial performance degradation at other than optimum altitudes.
> ...


(Sorry for P-47-ing the thread, again)

Hi, ren,
Would you please further elaborate the excerpt?


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## Colin1 (May 11, 2010)

Nikademus said:


> A good point


Why?
Paradoxically, in-theatre commanders would much rather their fighters didn't have to fight, it's just that that's invariably what happened. They'd have been quite happy not to have seen a single enemy fighter on the way in and out. Air forces exist to destroy enemy assets at minimum cost to themselves, not (necessarily) to engage other's air forces in a silly war of attacking each other's products.

There is of course a case for drawing an enemy air force directly into confrontation in order to wear him down but such a strategy is normally cognisant of the home team's advantage in numbers, technical superiority or scales of production. Or all three.

32,000ft is so many more thousands of feet that the enemy have to attain before he can consider intercepting you and so many more miles of penetration into his territory before he does. 32,000ft, like any altitude advantage, is a great perch for 'boom and zoom' despatching interceptors on their way up to do just that. What is the difference between turbocharged P-47s boom'n'zooming Ta152s on their way up to 32,000ft and what supercharged P-51s did to Fw190Ds on their way up to 25,000ft?

WWII was a fierce technology race and altitude performance was one of the markers underpinning that race, the ability to jab your enemy while staying out of reach of his jabs.

If the war had continued there is little doubt (in my opinion) that it would have been pushed higher, the war would have reached 32,000ft eventually; P-47Ns escorting B-32s in the ETO being intercepted by Ta152s at those altitudes is not an unrealistic scenario.


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## renrich (May 11, 2010)

TP, this quote came from a chapter in the book devoted to the Hellcat, which Linnekin flew early in his career. In this chapter Linnekin devotes a number of paragraphs to what he calls the myth that the Pacific War was fought mainly by aircraft that would not have been effective in the ETO. He makes the statement that "there were not that many legitimate 400 mph plus airplanes around, and it is questionable whether top speed, as such, ever got utilized in a fight. Certainly the ability to accelerate, as opposed to simply go fast, either to catch somebody or to escape, is valuable." He goes on to say that "The Corsair, at most "useful" altitudes was as fast as any and had substantial range and substantial load carrying ability. If you could figure some measurement scale that people would agree to, you could find support for the idea that the Corsair may have been the best/most effective fighter in all of WW2-until you factored in how many Corsairs were wrecked operationally by their own pilots. Oh well, nobody's perfect!"

From there he segues into the part about the P47 and it's performance at very high altitudes. Linnekin's book, IMO, is a gem. He began his career training in the Stearman and wound up flying high performance airplains like the F4 and he devotes chapters to how all the various planes he flew, actually flew. He is a graduate of the Naval Academy and the Navy Test Pilots school and is a aeronautical engineer and flew combat in Korea. At the end, he has a chapter about the "Little Guys" Mooneys, Citabrias, Pipers, etc.


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## DAVIDICUS (May 11, 2010)

"_If you could figure some measurement scale that people would agree to, you could find support for the idea that the Corsair may have been the best/most effective fighter in all of WW2-until you factored in how many Corsairs were wrecked operationally by their own pilots. Oh well, nobody's perfect!"_

As long as the measurement scale doesn't include how they fared in the role of fighter-bomber / fighter-ground attack that all fighters were pressed into. In mid 1946, with the benefit of hindsight through examining data from more than 22,000 sorties, the USN found that Corsairs were about 60% more likely to be lost from anti-aircraft fire than Hellcats when actually hit by anti-aircraft fire during the same time period, flying from the same carriers against the same targets on missions under the "same conditions" in "comparable operations" where the two aircraft received "about the same number of hits per sortie."

The Navy report stated, "The F6F appears to have had considerable advantage over the F4U when flown under the same conditions." Elsewhere in the report it tentatively stated the conclusion that, "The F6F was slightly superior to the F4U in combat, apparently chiefly because of its greater ability to survive damage." 

On another note, I don't think the P-47D had a climb advantage over the P-51D at 25,000 feet and 30,000 feet. It's performance was close enough though to prohibit the claim that it was an inferior mount though. (Speed, climb, dive, zoom climb and roll were all excellent.) At the Joint Fighter Conference in mid 1944, the voting evaluators (weighted 5:3 Navy pilots over Army pilots) voted the P-47D the best fighter over 25,000ft edging out the P-51D by 6 votes and the F4U-1D by 38 votes.

Below 25,000ft the P-47D didn't even register a single vote with the order going F8F, P-51D, F4U-1D all relatively close within 3 votes of each other. (As with the P-47D below 25,000ft, the F8F did not register a single vote for best fighter above 25,000ft.)


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## Shortround6 (May 11, 2010)

renrich said:


> The airplane had a huge turbo supercharger that, by a combination of drag and mechanical power bleed off must have caused a substantial performance degradation at other than optimum altitudes. I know a couple of people in a Bearcat squadron who had an inadvertant encounter with four late model P47s one day in 1947. ( Inadvertant, hell. The Bearcats jumped them. What did you expect. The P47s were there.) It was no contest- partly because the Bearcat, below 10000 feet, could do absolutely everything better than anything else with a propeller and at low altitudes could out accelerate most contemporary jets.



Kind of comparing Apples to Oranges here aren't we?

And I would like to know just what "mechanical power bleed off" you are referring to for the P-47.

That was the whole point of the turbo charger, use the power of the exhaust to run the supercharger rather than powering the the first stage of the supercharger using crankshaft power. 

F8F also carried a bit less internal fuel than the P-47. One source giving 185 US gallons vs 370 gallons for most of the P-47Ds let alone the tankage in a "N". Cutting the guns from 8 to four didn't hurt and dropping over 50 sq ft of wing didn't hurt either. 

Trying the combat at even 20,000-25,000 ft might have given rather different results also. 

One reason the F8F was so small was that they "lost" the two stage mechanical supercharger of the F6F and F4U with its associated inter-cooler and were fitted with either a mechanical 2 speed drive on the F8F-1 or a variable speed hydraulic drive on the F8F-2 for the single stage supercharger. 

While all the R-2800s in the P-47, F4U, and the F6F were rated at either 2000 or 2100hp for take-off (by the factory and without water injection) the altitudes at which they would maintain "military power" are rather informative. 
The 2000hp engine of the P-47Ds was good for 2000hp military power to 25,000ft
The 2100hp engine of the P-47Ns was good for 2100hp military power to 28,500ft.
The 2000hp engine of the F6F and F4U was good for 1800hp at 15,500ft and 1650hp at 22,000ft.
Later F4U engines could do better
The 2100hp engine in the F8F-1s was good for 1700hp at 16,000ft. 
The 2250hp engine in the F8F-2s was good for 1600hp at 22,000ft but the first F8F-2 with this engine wasn't delivered until 1947. 

The Non-turbo engines will, of course, have some measure of exhaust thrust to add to their mechanical HP but their longer exhaust passages compared to the V-12 engines cuts that a bit and since exhaust thrust works better the higher you go it may not have been a really big difference below 10,000ft although helping to even things up at higher altitudes. Exhaust thrust is also highly speed dependentant so that while it helps a lot in a high speed dash it doesn't work so well for climb performance. 

It is amazing what 2-3 years of aeronautical knowledge would buy you in the WW II era let alone what 3-5 years would buy in engine and supercharger design. The -30 engines used in the F8F-2s were almost identical to the -32 engines used in the F4U-5 Corsairs except for the deletion of the sidewinder 1st stage superchargers and the intercooler setup.


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## T Bolt (May 11, 2010)

double post


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## T Bolt (May 11, 2010)

I totally agree with Shortround's above post.


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## DAVIDICUS (May 11, 2010)

_"[T]he altitudes at which they would maintain "military power" are rather informative." _

The late war P-47D could pull its maximum 2,600hp in WEP up to close to 26,000ft.


* EDITED to correct from 24,000ft to 26,000ft


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## Shortround6 (May 11, 2010)

DAVIDICUS said:


> The late war P-47D could pull its maximum 2,600hp in WEP up to close to 24,000ft. Does someone know the WEP ratings for the other aircraft at that altitude?



I was trying to show a basis for comparison

once you get into which planes had water injection and when or try to use WEP both with and without water injection things get real complicated real quick.

The navy planes are going to be 350hp or more behind the P-47 from about 22,000ft on up even with water injection and the higher you go the worse it is going to get. In fact the Navy planes aren't going to get much benefit from water injection once they go over the critical altitude because the supercharger just doesn't have any excess capacity.


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## DAVIDICUS (May 11, 2010)

"_I was trying to show a basis for comparison_"

I know. I'm interested in figuring out the maximum HP of the other types at WEP regardless of whether they have water injection.

"_The navy planes are going to be 350hp or more behind the P-47 from about 22,000ft on up even with water injection_"

The August 1945 Final Report - Evaluation of Maximum Practical Combat Power Rating For The F4U-1 Airplane indicates 1,650hp at 23,500ft. That's with water injection.

I have data for the Hellcat but it is an early model. I don't have anything for the Bearcat.


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## tomo pauk (May 12, 2010)

Shortround6 said:


> Kind of comparing Apples to Oranges here aren't we?
> 
> And I would like to know just what "mechanical power bleed off" you are referring to for the P-47.
> 
> ...



That's why I've asked about turbo allegedly 'stealing' the power from engine - not true, as we know it


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## Nikademus (May 12, 2010)

Colin1 said:


> Why?




Because highlighting a plane's alleged performance advantage at a height where very little actual combat took place while either downplaying or not mentioning at all those lower altitudes where combat did take place tends to give a skewed picture. Same goes for situations where a plane subtype that saw little or no combat gets used in place of a more common sub-model.


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## DAVIDICUS (May 12, 2010)

* CORRECTION * 

I think I was mistaken in asserting that the late war P-47D could hold it's power up to about 24,000ft. I believe it is actually about 26,000ft.


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## Colin1 (May 12, 2010)

Nikademus said:


> Because highlighting a plane's alleged performance advantage at a height where very little actual combat took place...


There's an explanation in there somewhere
why do you suppose very little actual combat took place at 32,000ft? Because pilots found it disagreeable? Or because one side couldn't actually get to 32,000ft or at least not in any numbers? If you are penetrating enemy territory in large, strategically significant numbers escorting bombers capable of tremendous damage and notwithstanding this, there's still 'very little actual combat taking place' then your performance advantage isn't alleged, it's real.

The performance margin between the P-51 and its principal Luftwaffe rivals closed beneath its 'performance advantage height' of 25,000ft.


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## Shortround6 (May 12, 2010)

Nikademus said:


> Because highlighting a plane's alleged performance advantage at a height where very little actual combat took place while either downplaying or not mentioning at all those lower altitudes where combat did take place tends to give a skewed picture. Same goes for situations where a plane subtype that saw little or no combat gets used in place of a more common sub-model.



No single piston powered aircraft could be optimized for peak performance at all altitudes. Compromises had to made. The question is wither the compromises were so sever as to seriously limit the planes combat ability at the altitudes it was not designed for. 

The Americans spent a lot of time and money trying to develop and deploy bombers that would operate at 30,000ft and above. The British had several high altitude projects going including high altitude interceptors (see Westland Welken). Germans had a number of high altitude projects and some operational recon planes (JU 86). 
Even the French had a prototype bomber with a third engine in the fuselage driving a supercharger for the wing mounted engines in 1939-40. 
It turned out that high altitude operations were harder than it was first thought but without 20/20 hindsight who would have neglected or written off combat over 30,000ft when planning aircraft in WW II? With 2-4 years from issuing the requirement to getting operational aircraft in squadron service waiting until the enemy is overflying you at 35,000-45,000 ft is a little late to be placing orders.


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## renrich (May 12, 2010)

Shortround, in my earlier post I was using a direct quote from a book written by an experienced pilot, test pilot and aero-engineer. I won't try to argue any points about drag caused by super chargers or turbo super chargers because I don't know that much about it. Linnekin flew operationally, Hellcats, Bearcats, Corsairs, Panthers, Crusaders, et al. and his opinions seem worthy of consideration. I have mentioned this before, also, one of my many uncles was an IP during WW2 and flew P39s and P47s among others. He told me that when he flew P47s and they went to gunnery ranges they would often be bounced by F4Us and that they could not compete with them. I doubt the Corsair could compete with a P47 much above 25000 feet so those mock dogfights must have occurred at lower altitudes. In Blackburn's book about the Jolly Rogers, I seem to remember mention of the Corsairs superiority over P47s and the P47 pilots trying to get them to go upstairs which the Corsair pilots sensibly declined.

The interesting thing about the 1944 fighter conference which Davidicus mentioned is that the F4U4 was at that conference and was included in some of the voting but not all. In some of the votes the F4U4 came in BEHIND the F4U1D. I don't get that because the F4U4 was a much better performer than the F4U1D and I have read in many places that it was the nicest flying Corsair of all. I guess we will never know.


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## renrich (May 12, 2010)

Shortround, in my earlier post I was using a direct quote from a book written by an experienced pilot, test pilot and aero-engineer. I won't try to argue any points about drag caused by super chargers or turbo super chargers because I don't know that much about it. Linnekin flew operationally, Hellcats, Bearcats, Corsairs, Panthers, Crusaders, et al. and his opinions seem worthy of consideration. I have mentioned this before, also, one of my many uncles was an IP during WW2 and flew P39s and P47s among others. He told me that when he flew P47s and they went to gunnery ranges they would often be bounced by F4Us and that they could not compete with them. I doubt the Corsair could compete with a P47 much above 25000 feet so those mock dogfights must have occurred at lower altitudes. In Blackburn's book about the Jolly Rogers, I seem to remember mention of the Corsairs superiority over P47s and the P47 pilots trying to get them to go upstairs which the Corsair pilots sensibly declined.

The interesting thing about the 1944 fighter conference which Davidicus mentioned is that the F4U4 was at that conference and was included in some of the voting but not all. In some of the votes the F4U4 came in BEHIND the F4U1D. I don't get that because the F4U4 was a much better performer than the F4U1D and I have read in many places that it was the nicest flying Corsair of all. I guess we will never know.


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## DAVIDICUS (May 12, 2010)

"_The interesting thing about the 1944 fighter conference which Davidicus mentioned is that the F4U4 was at that conference and was included in some of the voting but not all. In some of the votes the F4U4 came in BEHIND the F4U1D. I don't get that because the F4U4 was a much better performer than the F4U1D and I have read in many places that it was the nicest flying Corsair of all. I guess we will never know._"

The reason the rank for the F4U-4 was so low may be that relatively few pilots at the conference actually flew the aircraft. The Report lists the breakdown of comment cards turned in by pilots who flew the aircraft. Only three were turned in for the F4U-4. 

The P-47D had 29 comment cards.

The P-51D had 38 comment cards.

The F4U-1D had 28 comment cards.

The P-47M also didn't place in the rankings even though it had a clear performance advantage over the P-47D. I suspect that the reason for its rank in relation to the P-47D is the same as the reason for the F4U-4's rank in relation to the F4U-1D. (It also had few comment cards)

Related to Shortround6's comment, I recall that Robert Johnson, in his book, said that German fighters sometimes would try to sneak in at over 35,000ft. I'm frankly not sure what weight to assign to all the conflicting anecdotal accounts of pilots engaging in mock combat. Renrich's post that the Helldiver, aggressively flown, presented as much trouble as a late model P-47D was interesting. There is a person here on this forum (I don't recall his name) who recounted his father's experience flying mock combat in P-47N's against F4U-4's. He stated that the Thunderbolt pilots would try to get the Corsairs to come up over 15,000ft and the Corsair pilots would try to get the Thunderbolts to engage below 15,000ft. Each knew where their strengths and the other's weaknesses were. He also said that the P-47N would out roll and out zoom the F4U-4.

His father also flew P-51's and his father's opinion was that the P-51 was better than the P-47D under 30,000ft and that while the P-51 did most things better than the P-47, the P-47s most important advantage was that it would bring you home. There is a post I put up with pictures of damage that P-47's have absorbed and still managed to bring their pilots home.

http://www.ww2aircraft.net/forum/aviation/tree-trimming-army-air-force-style-24161.html

.
.


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## Nikademus (May 12, 2010)

Shortround6 said:


> No single piston powered aircraft could be optimized for peak performance at all altitudes. Compromises had to made. The question is wither the compromises were so sever as to seriously limit the planes combat ability at the altitudes it was not designed for.
> 
> <snip>
> It turned out that high altitude operations were harder than it was first thought but without 20/20 hindsight who would have neglected or written off combat over 30,000ft when planning aircraft in WW II?



I think you understand my point and I agree with both billets above. On the former, that was why i agreed with the Renrich's caution and expansion regarding the P-47's overall performance , who's attributes tend to get caught up in black and white comparisons, in part because much of it is speculation as there was very little fighter combat above 30,000 feet. Having seen may declarative posts (on other boards) about P-47's dancing all over the heads of Axis aircraft as if they were WWI relics at such altitudes was what led me to ask the basic question....how much actual combat supports such notions? I found there to be little to none which ties in to the 2nd billet. Indeed it was alot harder to fight at such altitudes. Even simply chasing down high flying recon planes proved challenging in terms of getting there and the aerodynamics involved in controlling one's plane.


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## davparlr (May 12, 2010)

renrich said:


> One man's account of P47 prowess in ACM and this was undoubtedly not at the P47s best altitude. Ralph Linnekin, "80 knots To Mach 2" " That useful altitude reference is in honor of the P47, which is difficult to categorise. The N version is credited with something on the order of 469 mph, but at 32000 feet. What reciprocating engine airplanes actually fought at 32000 feet?



Quite helpful if you had to deal with a Ta-152, which, by the way, it was as fast or faster from 15k ft to 35k ft.




> It may be useful to fly that high, but at what cost. The P47 was a very good airplane with a fine combat record. It was not, however lauded as a sterling performer.



Actually it was lauded by the Joint Fighter Conference as the best fighter above 25k ft, which is important in that the B-17 and B-29 flew at that altitude or higher. It certainly held the high ground in Europe.




> The airplane had a huge turbo supercharger that, by a combination of drag and mechanical power bleed off must have caused a substantial performance degradation at other than optimum altitudes.



I don’t know. The P-47M/N generated 2600 hp at SL and 2800 hp form 5k to 33k. I know of no other single engine aircraft that comes close to this power. 




> I know a couple of people in a Bearcat squadron who had an inadvertant encounter with four late model P47s one day in 1947. ( Inadvertant, hell. The Bearcats jumped them. What did you expect. The P47s were there.) It was no contest- partly because the Bearcat, below 10000 feet, could do absolutely everything better than anything else with a propeller



Well, bragging about jumping someone in you own back yard and winning is no big thing, kinda like a Zero pilot bragging about beating an F4U in a turning fight.

Lets look at some comparisons of the F8F-1, P-47D-25 with 44-1 fuel (post May, ’44), and P-47M/N, with equal loads (using F8F loaded weight minus empty weight or 2316lbs),

Loaded weight
F8F-1 9368 lbs
P-47D-25 12515 lbs
P-47M 12739 lbs
5k
HP available-power to weight-airspeed – rate of climb
F8F-1 1900 hp (est based on F4U pwr profile) -.203 hp/lb – 400 mph (est) – 4150 ft/min 
P-47D-25 2700 hp – .216 hp/lb – 372 mph – 3510 ft/min
P-47M 2800 hp - .220 hp/lb – 385 mph – 3880 ft/min

15k
F8F-1 1850 hp - .197 hp/lb – 415 mph (est) – 3850 ft/min (est)
P-47D-25 2700 hp – .216 hp/lb – 417 mph - 3500 ft/min
P-47M 2800 hp - .22 hp/lbs – 418 mph – 3560 ft/min

20k
F8F-1 unk hp – unk – 421 mph (max speed) – 3650 ft/min
P-47D-25 2700 hp - .216 hp/lb – 435 mph – 3300 ft/min
P-47M 2800 hp - .22 hp/lb – 437 mph – 3300 ft/min

Just looking at the comparison numbers, it is apparent that the late model P-47s were extremely powerful aircraft with even the equally loaded P-47D-25 having a better power to weight ratio, thus acceleration, than the F8F-1. An equally loaded P-47M would easily out accelerate the F8F-1 and had very similar performance above 10k ft and at 20k ft, would not only out accelerate the F8F-1 but also leave it behind. The F8F-1 was certainly a maneuverable hot rod and the P-47 pilot would have to make sure he had a significant advantage in attacking below 15ft or go somewhere else, like they always had to do. However, they could always pounce from above.

P-47D data was taken from 44-1 fuel test with corrections for weight. 

P-47M data was from various official sources, either military flight test or supplier data.

F8F-1 data was based on fixed point data of, 2100 hp and 382 mph at SL, max speed of 421 mph at 19,700 ft, and 1850 hp at 15,500 ft. Estimates beyond this were based on fixed point data modified by typical F4U-4 performance in hp, climb and speed. This is sometimes dangerous, but is probably a reasonable rule of thumb. 




> and at low altitudes could out accelerate most contemporary jets.



I kind of feel that the SNJ would out accelerate a contemporary jet.



> Nonetheless, our guys said that AD Skyraiders and even SB2C Helldivers flown aggressively had at other times given them as much trouble as the P47s.



A lightly loaded attack bomber, especially an AD with 2500 hp and low wing loading could certainly be a formidable adversary in turning fight, same too with the SB2C only not as much so, but again, you don’t want to turn with one.


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## renrich (May 12, 2010)

Thanks, Davidicus, for clearing up the issue about the F4U4. I have always wondered about that. An amusing story about F4Us in Guyton's book. On May1, 1945, three land based Marine pilots in F4Us on a 30000 foot patrol from Okinawa wandered too far at sea and ran low on fuel. They were almost out of fuel when CV Yorktown heard their distress calls and directed them to land aboard. None had ever made a carrier landing. " One, after a perfect landing asked: What was that man doing waving those paddles back there?" " Brother,' he was told, " he was the landing signal officer and he was giving you a wave off."


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## renrich (May 12, 2010)

Thanks, Davidicus, for clearing up the issue about the F4U4. I have always wondered about that. An amusing story about F4Us in Guyton's book. On May1, 1945, three land based Marine pilots in F4Us on a 30000 foot patrol from Okinawa wandered too far at sea and ran low on fuel. They were almost out of fuel when CV Yorktown heard their distress calls and directed them to land aboard. None had ever made a carrier landing. " One, after a perfect landing asked: What was that man doing waving those paddles back there?" " Brother,' he was told, " he was the landing signal officer and he was giving you a wave off."


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## renrich (May 12, 2010)

Dav, my reading on B17 missions in the ETO indicates that they seldom flew missions as high as 30000 feet. More like low twenties to twenty five thousand feet. Loaded B24s even lower.


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## renrich (May 12, 2010)

Dav, my reading on B17 missions in the ETO indicates that they seldom flew missions as high as 30000 feet. More like low twenties to twenty five thousand feet. Loaded B24s even lower.


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## drgondog (May 12, 2010)

renrich said:


> Dav, my reading on B17 missions in the ETO indicates that they seldom flew missions as high as 30000 feet. More like low twenties to twenty five thousand feet. Loaded B24s even lower.



That would correct. The Early Days with the Brits were the only missions really flown at 30,000 feet.

SOP was for the Forts to fly 22K to 26+K with most missions flown at 24-26,000 feet (low to high boxes) and the B-24s at 20-22K..


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## Colin1 (May 12, 2010)

renrich said:


> Dav, my reading on B17 missions in the ETO indicates that they seldom flew missions as high as 30000 feet. More like low twenties to twenty five thousand feet. Loaded B24s even lower.


Would this be a command preference, or down to platform limitations (esp the ability of the crew to operate at 30,000ft) and bombing accuracy?


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## Nikademus (May 12, 2010)

Ceiling limits while loaded, balancing bomber accuracy with the threat from flak (and fighters) and impact on crews and equipment.


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## Colin1 (May 12, 2010)

Nikademus said:


> Ceiling limits while loaded, balancing bomber accuracy with the threat from flak (and fighters) and impact on crews and equipment.


...is pretty much the perfect answer
So we're coming to the close of the war and we're learning. We now know what it takes to get a platform up there and this know-how is manifested in aircraft like the P-47N, the B-29 and from Germany, the Ta152.

The problem with the end of the war (for Germany) is that she has precious few resources to see off the B-17/B-24 and incumbent escort raids, let alone develop and build for a fight at a new altitude; the Ta152 was good enough, just not numerous enough (or in-time enough). The lack of combat at 30,000ft, for me, can be attributed to a lack of opposition rather than any lack of plausibility.


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## davparlr (May 12, 2010)

renrich said:


> Dav, my reading on B17 missions in the ETO indicates that they seldom flew missions as high as 30000 feet. More like low twenties to twenty five thousand feet. Loaded B24s even lower.



I worded that poorly. I meant that the B-17 flew at 25k, but B-29 flew higher. P-47Ns were active in the Pacific.


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## Shortround6 (May 12, 2010)

renrich said:


> Dav, my reading on B17 missions in the ETO indicates that they seldom flew missions as high as 30000 feet. More like low twenties to twenty five thousand feet. Loaded B24s even lower.



This may be quite true but what altitude were they designed to fly at?

And how much higher should the escorting fighters be able to fly/fight?

Germans were fitting Nitrous oxide systems for use at what altitudes?

Germans were fitting pressure cabins to some 109Gs

Germans had been working on two stage superchargers in addition to turbos and had tried the central auxiliary engine on both the Henschel 130 and the Do 217

And I guess the Navy had it wrong when they ordered the F4U-5 with the sidewinder supercharger set up to act as high altitude planes over the Bearcats?


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## DAVIDICUS (May 12, 2010)

While not a rule of thumb, it was not rare at all to have enemy aircraft approaching at 28,000ft and higher. I pulled these in about 15 minutes.

P-51's

http://www.spitfireperformance.com/mustang/combat-reports/4-fiedler-29march44.jpg

http://www.spitfireperformance.com/mustang/combat-reports/4-grounds-19july44.jpg

http://www.spitfireperformance.com/mustang/combat-reports/4-hofer-24may44.jpg

http://www.spitfireperformance.com/mustang/combat-reports/4-lajeunesse-30may44.jpg

http://www.spitfireperformance.com/mustang/combat-reports/20-black-14jan45.jpg

http://www.spitfireperformance.com/mustang/combat-reports/20-fiebelkorn-28sept44.jpg

http://www.spitfireperformance.com/mustang/combat-reports/20-jones-d-14jan45.jpg

http://www.spitfireperformance.com/mustang/combat-reports/20-kelso-14jan45.jpg

http://www.spitfireperformance.com/mustang/combat-reports/20-nichols-14jan45.jpg

P-47's

http://www.wwiiaircraftperformance.org/p-47/er/353-kinkade-14oct43.jpg

http://www.wwiiaircraftperformance.org/p-47/er/353-newman-14oct43.jpg

http://www.wwiiaircraftperformance.org/p-47/er/361-webb-30jan44.jpg

http://www.wwiiaircraftperformance.org/p-47/er/353-maguire-27sept43.jpg

http://www.wwiiaircraftperformance.org/p-47/er/361-sedman-30jan44.jpg

http://www.wwiiaircraftperformance.org/p-47/er/361-lederer-30jan44.jpg

http://www.wwiiaircraftperformance.org/p-47/er/361-latimer-30jan44.jpg

http://www.wwiiaircraftperformance.org/p-47/er/353-lefebre-22dec43.jpg

http://www.wwiiaircraftperformance.org/p-47/er/355-woertz-29nov43.jpg

http://www.wwiiaircraftperformance.org/p-47/er/355-olson-21feb44.jpg

http://www.wwiiaircraftperformance.org/p-47/er/353-rimerman-27sept43.jpg


This one made me laugh out loud:

"*After this I called for a join up of the Squadron at 18,000 on the bombers. My No. 3 and I flew about 70 degrees for a few minutes and came up on the B-17's again. I saw 4 P-51's chasing something so flew over to investigate and took a left turn over them. I had just about found out that it was an ME-109 but too late. Another one came from behind me and laid in several nice close 20mm. Two in the right wing root knocking out the flap, wheel, which burned out, and aileron. Two in the right elevator and several in the fuselage and prop. Those things give you a start for a while but you can usually bring a P-47 home. P.S. This is in no way to be used as an advertisement for the thing though. Well we got home to learn that two of the boys had shot the Jerry ---- so and so down. They didn't even let him jump out.

I claim one FW-190 destroyed because I saw him strike up and go down burning --- two FW-190's damaged as I saw the strikes. -- I also claim one P-47 to be repaired.*"

http://www.wwiiaircraftperformance.org/p-47/er/353-duncan-12may44.jpg

.


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## renrich (May 12, 2010)

SR, the F4U4 had a service ceiling in excess of 41000 feet. The F4U5 the same except it developed more HP. Please enlighten me as to what a "sidewinder supercharger" is.


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## Shortround6 (May 12, 2010)

For those who are interested there are several charts over on the Spitfire performance website. 

One for the P-47 that is rather interesting: scroll down to the Oct 11 1943 test for the P-47D.

P-47 Performance Tests

This test lists altitude, manifold pressure, horsepower, turbo RPM, exhaust back pressure, and carb temperature in addition to speed. 

This gives a pretty good idea of the operation of the turbo charger. It was basically idling at sea level with just about all pressure coming from the engine driven supercharger. The work a supercharger does goes up with the square of it's speed so at sea level the turbo was doing about 1/9 the work it would be doing at 31,000ft when it hit 22,000rpm.
Please note also the difference between critical altitudes in high speed flight and while climbing. The speed of the air entering the intake duct (speed of the aircraft) means that there is a higher pressure going into the turbo during high speed flight than while climbing so you get more pressure out. 

This effect can also be seen in the Charts for the F4U:
F4U Performance Trials

Where the different altitudes for engine critical hight (no ram effect) and aircraft critical hight (with ram effect) are given.

Please also note the progressively lower altitudes going from normal power (max continuous) to military power power and, in later tests, War Emergency Power. The supercharger couldn't supply enough air to maintain the higher power ratings at the higher altitudes.


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## renrich (May 12, 2010)

SR, I had forgotten that the P47 had an engine driven supercharger in tandem with the turbo supercharger. That must have been what Linnekin was talking about " the combination of drag and mechanical power bleed-off" at low altiudes.


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## renrich (May 12, 2010)

SR, I had forgotten that the P47 had an engine driven supercharger in tandem with the turbo supercharger. That must have been what Linnekin was talking about " the combination of drag and mechanical power bleed-off" at low altiudes.


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## Shortround6 (May 12, 2010)

renrich said:


> SR, the F4U4 had a service ceiling in excess of 41000 feet. The F4U5 the same except it developed more HP. Please enlighten me as to what a "sidewinder supercharger" is.



The F4U-5 used the R-2800-32W engine.

See patent drawing:
http://www.ww2aircraft.net/forum/engines/radial-engine-2-stage-superchargers-r-2800-etc-17593.html

The two sideways (to american thinking) superchargers were run in parallel as the first stage and after the air went through the intercooler it was feed into the second stage impeller mounted in the usual place at the back of the engine. You can see the induction pipes leading from the supercharger casing to the cylinders in the drawing. 

This set up was rated at 1800hp at 30,000ft Military power compared to the 1800hp at 23,000ft military rating of the R-2800-18W used in the F4U-4. Or the 1500hp at 30,000 normal compared to the 1550hp at 26,000 normal rating of the R-2800-18W.


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## Shortround6 (May 12, 2010)

renrich said:


> SR, I had forgotten that the P47 had an engine driven supercharger in tandem with the turbo supercharger. That must have been what Linnekin was talking about " the combination of drag and mechanical power bleed-off" at low altiudes.



Except that the R-2800 in the F4U had an almost identical supercharger as it's second stage to supply boost at low altitude. The Navy two stage superchargers disconnected the 1st stage at low level to save power.

Without some sort of supercharger there is no way on god's green earth (or in his blue sky  ) that you are going to get over 30in of manifold pressure in an engine.


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## drgondog (May 12, 2010)

Shortround6 said:


> For those who are interested there are several charts over on the Spitfire performance website.
> 
> One for the P-47 that is rather interesting: scroll down to the Oct 11 1943 test for the P-47D.
> 
> ...



SR - that test was performed with a D-10 w/WI but it was unclear whether the paddle prop was installed


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## drgondog (May 12, 2010)

DAVIDICUS said:


> While not a rule of thumb, it was not rare at all to have enemy aircraft approaching at 28,000ft and higher. I pulled these in about 15 minutes.
> 
> 
> .



It was common to see the 'escort' 109s come from 30-32000 feet and for 51s (or 47s) to spot them and climb to that altitude to engage. My father met one at 30K and chased him to the deck before he got it..


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## DAVIDICUS (May 12, 2010)

Then it was more common than I thought. 

I also noticed that ME-109's would fly top cover for FW-190's.


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## Shortround6 (May 13, 2010)

drgondog said:


> SR - that test was performed with a D-10 w/WI but it was unclear whether the paddle prop was installed



I was more interested in the relationship between altitude and the manifold pressure/power of the engine and how it related to the exhaust turbine speed and exhaust back pressure than in the actual performance. For instance you may have noted that at a steady manifold pressure of 56 in the power output varies in relation to the exhaust back pressure.

It illustrates how the turbo allowed a steady hp output instead of the saw tooth profile of a multi speed geared supercharger. It also illustrates the the higher altitudes the turbo allowed compared to even very good mechanical 2 stage engines. 

Later aircraft with improved propellers and and later model engines and with improved turbines/compressors using higher manifold pressures can, of course do much better


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## Vincenzo (May 13, 2010)

drgondog said:


> SR - that test was performed with a D-10 w/WI but it was unclear whether the paddle prop was installed



there is the name of propelelr in the test need only know what are i think they are the not paddle (i'm talking of 11th ocotber '43 test of 43-75035 if you talking an other test sorry)


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## Nikademus (May 13, 2010)

dup post. server issues.


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## Nikademus (May 13, 2010)

Colin1 said:


> ...is pretty much the perfect answer
> The lack of combat at 30,000ft, for me, can be attributed to a lack of opposition rather than any lack of plausibility.




I disagree. It appears to me that the prime determinant of chosen altitude was driven primary by the German ground defenses, (aka "flak") balanced against the need for accuracy, particularily in the case of the Eighth AF with it's stated goal of "precision" bombing. The average altitude settled upon for this was around 21,000 feet. (RAF had started bombing in 39 at 9-11,000 but quickly got schooled)

Despite this lofty height, German Flak defenses took a terrible toll on the Eighth over the course of the campaign in terms of damage, casualties and outright losses. Additionally the defenses had a measurable impact on accuracy. In spite of this, the USAAF continued to attack around this altitude band. If accuracy could have been mainained at much higher altitudes while reducing losses and damage vs. said defenses, I think Eaker and company would have done so.


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## drgondog (May 13, 2010)

DAVIDICUS said:


> Then it was more common than I thought.
> 
> I also noticed that ME-109's would fly top cover for FW-190's.



I haven't found an 'exact date' for the LW changes to tactics but the 8th (particularly the Target Escorts) began seeing the 'top cover' Me 109s in the April 1944 timeframe when it became clear the pre-Sturm Fw 190s were struggling against the Mustangs at bomber altitudes - and nearly mandatory when the Sturm Fw 190A8's reached combat levels of deployment. It was quite common in June/July and then the rest of the war.

Later, when there was enough warning to assemble and form up, the Fw 190s would try to stage at 28-27,000 feet and go slightly 'downhill' (still with top cover w/109G A/S) to try to make one company front attack and then head for the deck.


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## drgondog (May 13, 2010)

Nikademus said:


> I disagree. It appears to me that the prime determinant of chosen altitude was driven primary by the German ground defenses, (aka "flak") balanced against the need for accuracy, particularily in the case of the Eighth AF with it's stated goal of "precision" bombing. The average altitude settled upon for this was around 21,000 feet. (RAF had started bombing in 39 at 9-11,000 but quickly got schooled)
> 
> Despite this lofty height, German Flak defenses took a terrible toll on the Eighth over the course of the campaign in terms of damage, casualties and outright losses. Additionally the defenses had a measurable impact on accuracy. In spite of this, the USAAF continued to attack around this altitude band. If accuracy could have been mainained at much higher altitudes while reducing losses and damage vs. said defenses, I think Eaker and company would have done so.



In 1945 there were far more missions flown at 18-20K, particularly when cloud cover was 10/10 over the continent, than 1944. Radar directed blind bombing was more effective and the optical tracking AA was ineffective.

However the prime altitude for the lead groups in the middle of the stack was ~ 24-25,000 feet for B-17s and was SOP for clear days even in 1945... lower for the B-24s.


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## Colin1 (May 13, 2010)

Nikademus said:


> ...the average altitude settled upon for this was around 21,000 feet
> 
> Despite this lofty height, German Flak defenses took a terrible toll on the Eighth... ...If accuracy could have been mainained at much higher altitudes while reducing losses and damage vs. said defenses, I think Eaker and company would have done so.


Someone got their sums wrong, the 88mm could range between 32 and 35,000ft.

Maybe Arnold thought so too, he relieved Eaker for Doolittle in 1943.

The next round of aircraft design was being built, among other things, to fly higher. I'm not even sure if the B-29 was next round or next generation. The air war was being pushed upwards as a natural reflex in avoiding the defences of the enemy. I don't really understand why you can't envisage combat at 30,000ft+ just because the war didn't last long enough for that to happen.

Lauding the P-47N for its high altitude performance whilst ignoring its shortfalls at altitudes lower, no more gives a 'skewed picture' than would pushing an F8F up to 30,000ft to expose its shortfalls; horses for courses.


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## DAVIDICUS (May 13, 2010)

In the Korean war, our pilots would enter Mig Alley in successive four aircraft flights spaced five minutes apart. These flights would enter the airspace staggered between 30,000 and 35,000 ft. Migs, with their higher operational ceiling, would usually bounce from high above, often approaching at altitudes over 45,000ft. Once the bounce was seen, the rest of the four ship groups would converge in a counterattack.


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## davparlr (May 16, 2010)

Colin1 said:


> Someone got their sums wrong, the 88mm could range between 32 and 35,000ft.



Some interesting information on gun coverage and altitude. A 35k ft range antiaircraft gun could cover a radius of 3.3 miles (34 sq. miles) at 30k ft, 4.6 mile radius (66 sq miles) at 25k ft., or 5.4 miles (92 sq miles) at 20k ft. An aircraft, flying directly overhead at 30k ft. and a ground speed of 250 mph, will be exposed to 22 rounds of Flak at 15 rds/min, at 25k, it will be exposed to 35 rds, and at 20k, it will be exposed to 38 rounds.

A bomber flying at 20k ft, say a B-24, will have an 8% higher risk than a B-17 at 25k, and 72 % higher risk than a B-29 flying at 30k. The B-17 will have a 60% higher risk than the B-29. A plane flying above 30k would, for all practical purposes, have to be directly overhead to be hit by the gun.

Altitude also provides benefit against fighters. While bombers typically do not maneuver, fighters do, and altitude affects maneuverability similar to adding gross weight. A nimble fighter at 25k could be quite sluggish at 30k.

It also should be noted that the B-29 is much faster than the B-17/24, also significantly reducing the exposure time. 

For the bomber, even more so than a fighter, airspeed and altitude is life. It is easy to see the lure of high altitude, high speed bombing.

Countering all this is bombing accuracy.

These are all rough estimates.


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## Colin1 (May 17, 2010)

davparlr said:


> It is easy to see the lure of high altitude, high speed bombing.
> 
> Countering all this is bombing accuracy.
> 
> These are all rough estimates.


Good info Dave
agree with your conclusions


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## Milosh (May 17, 2010)

Colin1 said:


> Someone got their sums wrong, the 88mm could range between 32 and 35,000ft.



88mm Flak 18, 36 and 37 

Maximum range :
Horizontal 16,200 yd
Vertical 39,000 ft
*Maximum effective ceiling* 25,000 ft (at 70-deg elevation )

from http://www.lexpev.nl/downloads/tme9369agerman88mmgun.pdf


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## Shortround6 (May 17, 2010)

*Maximum effective ceiling

Can be the altitude at which a gun get get off a reasonable number of shots at a target flying straight and level.

It is often governed by the shells fuse. Most if not all AA shells having a self destruct that functions at the end of a certain time period. Since all time fuses have a + and - tolerance and since the shells have slowed considerably by the time they get to 25,000ft or better getting the shell to burst at the right height (even if the line of flight intersects the bombers path) gets harder and and harder as the height goes up.*


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## Milosh (May 17, 2010)

It is my understanding is that is the distance/height at which there was a reasonable chance of making a hit.

Other effective ranges:

20mm > ~1100m
37mm > ~1600m


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## Nikademus (May 17, 2010)

Colin1 said:


> Someone got their sums wrong, the 88mm could range between 32 and 35,000ft.
> Maybe Arnold thought so too, he relieved Eaker for Doolittle in 1943.



Doolittle took over in 1944, and the Eighth continued to bomb well below 30,000 feet.


> I don't really understand why you can't envisage combat at 30,000ft+ just because the war didn't last long enough for that to happen.



Since the subject of Renrich's comments concerned what did happen vs. what might have happened had the war continued, I found his points to have merit.


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## renrich (May 17, 2010)

Dav, your post was very informative and obviously makes a lot of sense. I think another point is that the B29 was pressurized(?) and of course the B17s and B24s were not. I have read that at some times the casualties in the eighth air force caused by frostbite were higher than those caused by battle.


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## davparlr (May 17, 2010)

Nikademus said:


> Doolittle took over in 1944, and the Eighth continued to bomb well below 30,000 feet.



I would guess that a contributing factor may have been that none of his aircraft could perform a mission at that height.


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## Nikademus (May 17, 2010)

davparlr said:


> I would guess that a contributing factor may have been that none of his aircraft could perform a mission at that height.



Yes, in the case of the B-24. The B-17's operational ceiling is quoted as 30k in one book on the campaign. (Westerman or Neillands). Other factors were also involved as mentioned including accuracy. Westerman (Flak: German AA defenses 1914-1945) also wrote that ultra high bombing missions were enshewed due to the impact on equipment and crew (as well as accuracy) This is not to say that a few missions wern't attempted but generally the lead BG's flew in at around 23-25k. Eaker's relief had nothing to do with misjudging the ceiling of German flak defenses.


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## Colin1 (May 17, 2010)

Nikademus said:


> Yes, in the case of the B-24. The B-17's operational ceiling is quoted as 30k in one book on the campaign. (Westerman or Neillands). Other factors were also involved as mentioned including accuracy. Westerman (Flak: German AA defenses 1914-1945) also wrote that ultra high bombing missions were eschewed due to the impact on equipment and crew (as well as accuracy) This is not to say that a few missions wern't attempted but generally the lead BGs flew in at around 23-25k.
> 
> Eaker's relief had nothing to do with misjudging the ceiling of German flak defenses.


So in other words, it was platform limitations that pegged strategic bombing at around the 25,000ft mark, rather than any Command preference

Nobody said it was


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## Nikademus (May 17, 2010)

Colin1 said:


> So in other words, it was platform limitations that pegged strategic bombing at around the 25,000ft mark, rather than any Command preference
> 
> Nobody said it was



Your citing Eaker's replacement by Doolittle was suggestive that Eaker was relieved due to an error in judgement regarding enemy flak attributes and that changes were effected after his replacement (re: altitude). Neither was the case from what i have read. Platform limitations were _one_ of the factors that helped determine USAAF altitude settings but not the only one.


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## Shortround6 (May 17, 2010)

I would note that the Germans designed, built and fielded higher velocity 88mm AA guns, 105mm AA guns and 128mm guns and were investigating even larger AA guns, all with idea of increasing the effective ceiling of the Flack defense. 

See also the British AA gun history as well as the American 105 and 120mm AA guns. 

An awful lot of weapons planned and built to defend against things that never really panned out. 

But if the predictions had been true and the weapons not built were would the defense be?


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## davparlr (May 17, 2010)

Shortround6 said:


> I would note that the Germans designed, built and fielded higher velocity 88mm AA guns, 105mm AA guns and 128mm guns and were investigating even larger AA guns, all with idea of increasing the effective ceiling of the Flack defense.



My research shows that the 10.5 Flak 38 did not have the range of the 88. The 12.8 Flak 40 had a much better range but fired at a rate of 10 rnd/min. They doubled up to get 20 rnd/min but still had a limit quantity of guns available.


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## drgondog (May 17, 2010)

Nikademus said:


> Your citing Eaker's replacement by Doolittle was suggestive that Eaker was relieved due to an error in judgement regarding enemy flak attributes and that changes were effected after his replacement (re: altitude). Neither was the case from what i have read. Platform limitations were _one_ of the factors that helped determine USAAF altitude settings but not the only one.



I have heard repeatedly, by several individuals at a command level that their opinion bears weight, that Eaker was deemed to have failed to achieve the objectives necessary to make the case for US daylight strategic bombing - and the decision was made in the October timeframe.

In these discussions Eaker and Spaatz and Arnold were at odds regarding which changes in current strategy were required to a.) stop the bleeding and b.) win air superiority for the upcoming invasion.

The cornerstones of the debate were a.) switch to night bombing as requested by Churchill with a somewhat receptive audience in FDR, b.) violent disagreement from Eaker and Arnold for reasons ranging from training to equipment to logistics of cramming USAAF and RAF over UK in 10 hour window to perceieved ineffectiveness against both Luftwaffe and strategic targets.

From what I heard Eaker offered no real solutions and was not convinced that long range escort was the answer - as well as adamantly opposed to fighters ranging away from close escort.

Doolittle was a candidate for the 8th AF job but Eaker was well respected. The decision came down to Spaatz accepting the responsibilty for both the selection and the results of a new commander but USAAF Strategic Bombing doctrine was on the line and so was Spaatz's job.

The 8th conserved strength in late Oct through early January as the P-38 and then P-51 were evaluated for long range target capability... The reviews from Tommy Hitchcock who headed up 8th A technical evaluation were so glowing that the die was cast and the 354th FG was TDY from 9th AF to 8th and deals were cut to transfer 357FG to 8th in exchange for 358FG (jugs), as well as transfer all P-38s and P-47s to 9th AF TAC as all future deliveries for the P-51 were switched from 9th to 8th.

The die was cast in approximately November 1943 even before the first 354th FG mission was flown.. A HUGE gamble.

Flak effectiveness had nothing to do with the decision - it was all about killing the Luftwaffe as fast as possible and accept whatever casualties required by 8th BC to get the job done.

Doolittle made the command decision as new 8th AF CO and the infamous memo to 'seek the enemy in the air and on the ground' was one of his first, and early, directives.. I think January 11 but my memory is poor and I am away from my references. Many 8th BC Group Commander privately called Doolittle a 'murderer' for his decision to free up the escort as they envisioned a slaughter..


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## Vincenzo (May 17, 2010)

davparlr said:


> My research shows that the 10.5 Flak 38 did not have the range of the 88. The 12.8 Flak 40 had a much better range but fired at a rate of 10 rnd/min. They doubled up to get 20 rnd/min but still had a limit quantity of guns available.



afaik the 10.5 flak 38 was best of original 8.8/56 but badest of longer 8.8/71


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## Nikademus (May 17, 2010)

drgondog said:


> Flak effectiveness had nothing to do with the decision -
> ..



My point exactly in regards to Eaker.


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