SHOULD the P39 have been able to handle the Zero? Was it training or performance?

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This one?
 
Close, but she was blonde. Most Italian bars are run by families, or they are where I worked. The "staff" do the job as part of family life, not so much for the money, they frequently have other jobs. I knew one who was a linguist fluent in Latin, another was an art collector/trader, an expert in impressionist art and another was one of only three qualified female football referees in Italy. I cant say they were all beautiful but they were all stylish and interesting.
 
This is the crux of the whole discussion and what is slowly driving me nutz. The P 39N was in Production in December 1942 and the Spitfire mk IX was in squadron service during the previous summer. Would you replace Spitfire Mk Vs with P39-Ns or Mk IXs? and it isn't just a question of speed and rate of climb, it is also a question of serviceability, safety and loss rates. The P-39 was dangerous, relative to all other US fighters to its own pilots, even in training, I posted the stats and you made no comment. Using semantic tricks like "full series production" is not impressive, the fact is that the Mk IX was in production in mid 1942, there is a limit to how quickly any new type can be introduced and in terms of logistics switching all factories over when you don't have all the parts just means losing months of production. The Mk V may have been outclassed in 1942 but it was better than nothing.

Before the war started Hawkers were allowed to export Hurricanes because they could produce them faster than the RAF could train all their staff to use them. By 1940 production had doubled and each hurricane just got sent where it was needed because by that time everyone knew what it was, only pilots to fly them was an issue.
Not trying any semantic tricks. Squadron #64, #11, and #401 operational July '42 and #402 the next month with the Merlin 61, then from early 1943 with the Merlin 63, 66 and 70. So four squadrons in the last half of 1943. I would call that a good service test batch. They apparently did get into combat with victories in 1942 and having escorted some 8th AF short range missions.
 
As I said before the pilots were no match for the Japanese navy pilots. Our kids were green and the Japanese navy pilots were experienced. The P-39 (early heavy D,F,K and L) were all at least 30mph faster than the Zero at all altitudes. They were hard pressed to defend their base yet with all these disadvantages they managed a 1:1 kill ratio.

What do you mean by 'green'? The first US pilots to fly combat were career USAAC pilots.

1:1? Was that vs all Japanese a/c?
 
That's because it really didn't. In most reference books and other well respected sources the F6F-3 will show a reported service ceiling anywhere between 37,300 - 38,400 feet, and I've seen Navy reports showing as high as 38,600 feet in military power with an overload weight of 12,680lbs. The report you are referencing shows a particular P-39N (s/n 42-4400) at 7,274lbs with a ceiling of 38,500 feet. How is that any kind of real advantage? Plus, besides the occasional airplane doing reconnaissance work, who the heck was fighting at 38,000 feet anyway during WWII????



The Airacobra couldn't "handle the Zeros like the Hellcat" because speed isn't the only ingredient that makes an airplane a good fighting machine.The Hellcat had excellent handling and dogfighting capabilities, the Airacobra didn't. The Hellcat was immensely strong and could take a beating and still get the job done and bring the pilot home alive. The Airacobra wasn't. The Hellcat had long-range capability which allowed it to seek out and destroy the enemy wherever it may be. The Airacobra didn't. Lastly, the Hellcat never had to be stripped of guns, armor, or gasoline just to make it faster, climb better, maneuver quicker, or fly higher. The Airacobra DID!!!!!

Look, the Airacobra was a sleek little ship and did well on the post-war race circuit but it wasn't a truly war winning aircraft like you are trying to make it out to be, in any variant or any guise. I respect the men who flew her and that they were able to achieve some success because the odds were definitely stacked against them. And I really didn't want to pile on even more negative comments about your pet airplane but you left me no choice. :(

You are definitely a well-educated and learned man who knows a sh--t ton about aviation history. And I happen to like the Airacobra, all it's shortcomings notwithstanding. I have learned great deal about it from this thread and I thank you for it. Problem is, I'm left feeling that the Airacobra was even more of an abysmal failure than I believed it to be in the first place! Just please refrain from the wild-ass comments regarding it's supposed virtues and try concentrating on the proven characteristics of the machine, both the good and the bad. I think that approach might help sway people to your way of thinking, rather than saying the same unsubstantiated fact over and over hoping that it will eventually stick.

But that's just my opinion and one of many here on this forum....:salute:
My sincere apology. The official government/military tests on the P-39N (10/17/42) show a service ceiling of 38500' and the Hellcat (3/16/44) with 37000'. Top speed at 23000' (Hellcat critical altitude) of 379.5mph for the Hellcat and 375mph for the P-39N. At the Hellcat critical altitude of 23000' climb was 1500fpm while the P-39N climbed at 2285fpm. Thats 150% faster than the Hellcat. Same speed, faster climb. Not hearsay, official government tests. Tell me again how great a dogfighter the Hellcas was.
 
My sincere apology. The official government/military tests on the P-39N (10/17/42) show a service ceiling of 38500' and the Hellcat (3/16/44) with 37000'. Top speed at 23000' (Hellcat critical altitude) of 379.5mph for the Hellcat and 375mph for the P-39N. At the Hellcat critical altitude of 23000' climb was 1500fpm while the P-39N climbed at 2285fpm. Thats 150% faster than the Hellcat. Same speed, faster climb. Not hearsay, official government tests. Tell me again how great a dogfighter the Hellcas was.
Both were not as good as the 109G
Service ceiling - P39 38,500 109G 39,000+
Speed 23,000 ft - P39 375 mph 109G 403 mph
Climb at 23,000 ft - P39N 2,28 ft/min 109G 2,605 ft/min

plus of course the 109 was less likely to bite you
 
Not trying any semantic tricks. Squadron #64, #11, and #401 operational July '42 and #402 the next month with the Merlin 61, then from early 1943 with the Merlin 63, 66 and 70. So four squadrons in the last half of 1943. I would call that a good service test batch. They apparently did get into combat with victories in 1942 and having escorted some 8th AF short range missions.
What are you talking about? There were 5,656 Spitfire MkIXs built between June 1942 and December 1944. Are you saying there were 4 squadrons in service half way through the total production run? I am tired of this whac-a-mole discussion. Regardless of anything anyone posts you go back to the same issues every few days. I strongly suspect that you continue to insist the Luftwaffe was defeated in March 1944 to explain production of P-39s halting in May 1944.
 
excusing the typo of the production date (N production ended in APril '43)

we are back to repeating ourselves over the P-39s fuel capacity and performance. You don't get both the 120 gal fuel capacity and the the high rate of climb. Pick one.

The argument with the Spitfire is your claim that the P-40N could out climb everything but a Spitfire MK IX and your rather absurd claim that the Spitfire IX wasn't in full production until very late 1942 ( I guess the 4 squadrons at Dieppe in Augs were just using dozens of the prototype MK IXs?).

Against the much older MK V your one test P-39N may be technically ahead, but not by much, if any, at certain altitudes and not enough to make a real difference even at 20-25,000ft.

There was no gradually reduced capacity to as little as 86 gallons. you either had the full suite of 12 fuel cells with 120 gallons or you had the 8 tank suite of 87 gallons. The one gallon difference can be written off as a difference in translations or counting full fuel vs usable fuel.
Some loadings of the P-39 count 104 gallons of fuel but that is simply not filling the 120 gallon tanks all the way. Early P-51 loadings show 105 gallons of fuel "normal" and 180 gallons as overload. There were never 105 gallon tanks. Same with some P-40 loadings and many navy weight charts.

Please note that a full set of self-sealing fuel tanks for the P-39 weighed close to 290lbs so taking out the 4 smallest tanks/cells with the worst capacity to weight ratio is going to save a lot more weight than just the 33 gallons of fuel. The self sealing material was heavy. The production of the 87 gallon P-39s coincided with several light weight P-40 projects, culminating in the P-40N. Some of the P-40Ls had done the simple strip routine, yank a pair guns, yank some armor, yank a fuel tank and restrict ammo to the remaining guns. The P-40N was a much more thorough job, although yanking the electric starter and reducing the size of the battery went a little far, blaming the Russians for the reduction in fuel capacity for the P-39s seems a bit unfair unless you have actual documentation?

Please remember when judging use on the Russian front that most Russian aircraft had pretty poor armament by western standards. The LAGG-3 and Yaks having for the vast majority, a single 20mm and two 12.7mmm guns at best. Some deleted the 2nd 12.7mm gun due to weight/performance or supply issues? Some flew with a single 20mm, a single 12.7 and a single 7.62. LA-5s had two 20mm guns firing through the prop, lower cycle rate and ammo capacity was ??? Russian 20mm ammo used a light shell, about 75% the weight of the 20mm Hispano shell and with even less HE per shell. I would note that the Yak-9T with 37mm gun is usually credited with a single 12.7mm machine gun as additional armament.
Yes I DO get the 120 gallons with the high rate of climb. I'll stand by the P-39N test on 10-17-42 as being at the average weight of that particular flight. The weights listed on the official performance tests (not manifjold comparisons or propeller comparisons on the exact same plane ie weight is the same) all show the test article to be light by about half the weight of the internal fuel with full loads of ammo, oil etc. This was the AVERAGE weight of the plane on that particular flight.

P-39C 6689 test 7075 published weight difference 386# or 64 gallons
P-39D 7525 test 7850 " 325# 54
P-39M 7430 test 7650 " 220# 37
P-39N 7274 test 7650 376# 63

Every plane tested in an official performance test was lighter than published gross weight by roughly half the fuel. I can do this for the P-38 also but I'm not, look it up yourself. They are using an average weight for that particular flight on that day for calculations and ratios.

There certainly WAS a gradually reduced capacity. The N started with 120 gallons and was gradually reduced in subsequent production blocks until the Q had as little as 86 with the full 120 gradually restored in subsequent production blocks. The 104 gallon figure refers to the fuel left after deducting the 16 gallons in the reserve tank, actually a part of the inside left wing tank. Self sealing rubber fuel tanks weighed 260# total for the 12 tanks.

Most Russian fighters WERE underarmed by western standards. They referred to the 37mm cannon and the twin .50 caliber MGs (they deleted wing guns) as devastating armament with one hit from the cannon normally bringing down almost any plane. I agree with you on the Russian 20mm "light" shell and I believe the Germans 20mm was also light. I have seen comparisons where they say the American/British Hispano was the equivalent of three Browning .50 cal. MGs and the German 20mm was equivalent to 66% of a 20mm Hispano.
 
What are you talking about? There were 5,656 Spitfire MkIXs built between June 1942 and December 1944. Are you saying there were 4 squadrons in service half way through the total production run? I am tired of this whac-a-mole discussion. Regardless of anything anyone posts you go back to the same issues every few days. I strongly suspect that you continue to insist the Luftwaffe was defeated in March 1944 to explain production of P-39s halting in May 1944.
Look, I just went back and re-read the SpitIX vs Me109G comparison and that is what it states exactly. They had four squadrons of Spitfire IXs with Merlin 61s and they went to the Merlin 63, 66 and 70 in early 1943. Read it yourself. Like you said, they only made 5656 MK IXs, not a big run.
 
My sincere apology. The official government/military tests on the P-39N (10/17/42) show a service ceiling of 38500' and the Hellcat (3/16/44) with 37000'. Top speed at 23000' (Hellcat critical altitude) of 379.5mph for the Hellcat and 375mph for the P-39N. At the Hellcat critical altitude of 23000' climb was 1500fpm while the P-39N climbed at 2285fpm. Thats 150% faster than the Hellcat. Same speed, faster climb. Not hearsay, official government tests. Tell me again how great a dogfighter the Hellcas was.

Hellcat's rated altitude for climb was 20000-20500 ft for military power, not 23000 ft.
At 25000 ft, Hellcat climbed at 1280 - 1600 fpm (~12500 lbs, 'overload fighter' condition), P-39M at 1400 fpm (on 7430 lbs, ie. all 120 gals of fuel), P-39N at 1900 fpm (7274 lbs - reduced fuel), P-39Q at 1570 fpm (7871 lbs - ballasted to represent 120 gals of fuel and ammo for all 5 guns, gun pods present), but also just 1365. One does not need to be rocket scientist to see that reduction of weight improves rate of climb, while also reducing range and thence usability. We also have a thing where the Hellcat represents a good manered aircraft (just what was needed for naval fighters), unlike the P-39. Add the double the radius/range and Hellcat is a much more useful fighter.
About the RoF figure of 2285 fpm @ 23000 ft for the P-39N - what is the source?
 
Yes I DO get the 120 gallons with the high rate of climb. I'll stand by the P-39N test on 10-17-42 as being at the average weight of that particular flight. The weights listed on the official performance tests (not manifjold comparisons or propeller comparisons on the exact same plane ie weight is the same) all show the test article to be light by about half the weight of the internal fuel with full loads of ammo, oil etc. This was the AVERAGE weight of the plane on that particular flight.

P-39C 6689 test 7075 published weight difference 386# or 64 gallons
P-39D 7525 test 7850 " 325# 54
P-39M 7430 test 7650 " 220# 37
P-39N 7274 test 7650 376# 63

Unless ALL planes are tested this way the comparisons get hard to make and it doesn't matter how many times you repeat it, it doesn't make it true.
Some of the P-38 tests were done at absurdly low weights. I have already give you the fuel capacities or weights for the P-36 and P-40 tests and the reasons why, they were tested at the design weight but obviously they got lighter the longer the test lasted. Starting the test hundreds of pounds light is certainly shading things.

Every plane tested in an official performance test was lighter than published gross weight by roughly half the fuel. I can do this for the P-38 also but I'm not, look it up yourself. They are using an average weight for that particular flight on that day for calculations and ratios.

Please post link to ANY test were they SAY that is what they are doing. Your refusal to post sources is getting more than annoying.

There certainly WAS a gradually reduced capacity. The N started with 120 gallons and was gradually reduced in subsequent production blocks until the Q had as little as 86 with the full 120 gradually restored in subsequent production blocks. The 104 gallon figure refers to the fuel left after deducting the 16 gallons in the reserve tank, actually a part of the inside left wing tank. Self sealing rubber fuel tanks weighed 260# total for the 12 tanks.

You certainly have a different definition of gradually. Everything I have read says it was either/or. Either you had the 120 gallon tank set up once they had self sealing tanks or you had the 86/87 gallon setup. There was NOTHING in between.
Please give a reference for anything that says otherwise.

Refit kits were supplied to bring the fuel capacity back up to 120 gallons on the planes with the 86/87 gallon ( I am not going to argue about 1 gallon) tanks and NO the 86/87 tanks didn't start with the "Q" they started with the "N"s
Sources include AHT, "Cobra" By Birch Mathews (who says some of the Ms had 86 gallons)
Joe Baugher says that the Fuel reduction came after the first 166 "N"s with 2095 Ns being built.
 
Look, I just went back and re-read the SpitIX vs Me109G comparison and that is what it states exactly. They had four squadrons of Spitfire IXs with Merlin 61s and they went to the Merlin 63, 66 and 70 in early 1943. Read it yourself. Like you said, they only made 5656 MK IXs, not a big run.
You repeatedly take a factoid and extrapolate it. The 4 squadrons were issued with the MK IX then received an uprated version about 8 months later, but that is about how long a plane was used or superseded in service. The three American "Eagle Squadrons were issued with Mk IXs in September 1942. The Mk V was not being produced anymore, the RAF rarely had more than 1000 front line fighters in service but used over 2000 per year, that is how quickly a front line fighter becomes obsolete, lost, damaged or just worn out.

From Wiki
Operating within the RAF were three "Eagle" squadrons: units manned by American pilots who had joined the RAF. First formed in 1940 and initially equipped with Hurricanes, these units converted to Spitfire Vbs in 1941. They were re-equipped with Spitfire IXs in early September 1942 and were disbanded in late-September 1942 as their aircrew and aircraft were transferred to the fledgling USAAF's Eighth Air Force to become the nucleus of the 4th Fighter Group.[70]
 
Does the 5656 Spitfire IX number include the MXVI which was basically the same aircraft with a different engine and the Mk VIII with a similar performance?

Put the and if I remember the total came to about 8,250 give or take
 
Does the 5656 Spitfire IX number include the MXVI which was basically the same aircraft with a different engine and the Mk VIII with a similar performance?

Put the and if I remember the total came to about 8,250 give or take
No, I was using data from here.
Supermarine Spitfire (late Merlin-powered variants) - Wikipedia
Mark Built by Numbers Built Notes
F VII, H.F VII Supermarine 140 First Mk VII September 1942
F VIII, L.F VIII Supermarine 1,658 First Mk VIII 11 November 1942
F IX, H.F IX, L.F IX Supermarine, Castle Bromwich 5,656 First Mk IX BR581 June 1942
PR X Supermarine 16 First Mk X May 1944
PR XI Supermarine 471 First Mk XI November 1942
XVI Castle Bromwich 1,054 First Mk XVI October 1944
 
My sincere apology. The official government/military tests on the P-39N (10/17/42) show a service ceiling of 38500' and the Hellcat (3/16/44) with 37000'. Top speed at 23000' (Hellcat critical altitude) of 379.5mph for the Hellcat and 375mph for the P-39N. At the Hellcat critical altitude of 23000' climb was 1500fpm while the P-39N climbed at 2285fpm. Thats 150% faster than the Hellcat. Same speed, faster climb. Not hearsay, official government tests. Tell me again how great a dogfighter the Hellcas was.

You are quite the persistent fellow, I'll give you that much. So you want "official government/military tests" huh? Well besides the one I told you about in my last posting (s/n 42874/38,600 feet/report date 25 Apr 1945), there were these "official tests" as well....

Service ceiling results:
1) F6F-3 (s/n 42633) 38,000 feet. (report date 1 Sep 1944)

2) F6F-3 (s/n 02982) 38,900 feet. (report date 27 Nov 1944)

Maximum speed results (military power only):
1) F6F-3 (s/n 25820) 385 mph @ 23,500 feet. (report date 26 Aug 1943)

2) F6F-3 (s/n 41588) 382 mph @ 22,400 feet (report date 9 Jul 1945)

Do you happen to have more than one "official government/military test" showing the those particular numbers for speed and altitude of the most awesomeous P-39N that you tout so heavily? I'd love to see it, and I'm not being sarcastic. And surely you aren't suggesting that on any given day the average Airacobra could "handle" an average Hellcat in a one-on-one dogfight (pilot skill being equal of course)??? It had serious trouble with an airplane that basically had a 50 mph speed deficit so how could it ever deal with one that equaled and at times even surpassed it's own top-end speed????

I never disputed the superior climb rate of the P-39N, so why are you harping on it now? I've also never said that the speeds of the two types weren't for all intents and purposes roughly equal at altitudes exceeding 22,000 feet, as a few miles per hour here or there of difference wouldn't amount to a hill of beans in a real world situation anyway. But you can easily see from the testing I presented that the F6F-3 has obviously flown faster and climbed higher during some tests than others (and we haven't even discussed WEP yet). That's how it is because testing isn't performed in a vacuum. There's a lot of variables that come into play and these variables effect the outcome of tests (like temperature, wind velocity, pilot experience, aircraft weight, fit and finish of the particular aircraft, ect.)

I sincerely hope that you're not using the test results from 17 Oct 1942 as something ALL P-39Ns were capable of because that's a huge leap of faith my friend. I also hope that I didn't strike a nerve earlier regarding your beloved fighter, and if I did I truly apologize and wish no hard feelings between us going forward....:rolleyes:
 
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No, I was using data from here.
Supermarine Spitfire (late Merlin-powered variants) - Wikipedia
Mark Built by Numbers Built Notes
F VII, H.F VII Supermarine 140 First Mk VII September 1942
F VIII, L.F VIII Supermarine 1,658 First Mk VIII 11 November 1942
F IX, H.F IX, L.F IX Supermarine, Castle Bromwich 5,656 First Mk IX BR581 June 1942
PR X Supermarine 16 First Mk X May 1944
PR XI Supermarine 471 First Mk XI November 1942
XVI Castle Bromwich 1,054 First Mk XVI October 1944
Makes a decent number doesn't it
 
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