Groundhog Thread Part Deux - P-39 Fantasy and Fetish - The Never Ending Story (Mods take no responsibility for head against wall injuries sustained)

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This is a requirement of groundhogism. A point of view is never disproved by facts, after a few months rest it can be brought back again. It cannot be accepted that any combat took place in the BoB at 30,000ft because that would undermine the argument that the British rejected the P-39 (and P-40) for UK based operations because of performance not cost and spite.
 
Some of you guys (not all) need to understand the difference between service ceiling and combat ceiling. WW2 fighters very seldom got anywhere near their service ceiling when the plane climbed at only 100fpm. Mainly theoretical, this figure wasn't normally reached even during official tests. It was projected based on climb tests at lower altitudes. In test conditions, not in combat. I believe the British started the term combat ceiling which is the altitude at which a plane will no longer climb at 1000fpm. That's about as high as a fighter will want to go in combat. Climb is at or near full power at around 150-175mph IAS. Crawling up to 30000ft at that speed is hazardous to one's health in combat. And hard on the engine to be at full power for that long.

I never said nobody ever got to 30000ft in the BoB, just that it was extremely uncommon. And like victory claims, probably not that accurate. Just my opinion.
 
Would like to see those pilot manuals. All the information I have ever seen shows heated air ducted from the coolant radiator exhaust up to the cabin. Rated as very efficient cabin heat in Eglin Field tests. The P-400 used the fuel powered heater, I have seen that manual. That fuel powered heater may have been efficient but it caused radio static feedback, making either the heater or the radio unusable.
 
And you need to understand that it makes no difference what you call the ceiling. The LW sent recon planes over UK at extremely high altitude dropping bombs, eventually a modified Spitfire shot one down at 42,000 ft. One gun was jammed and every time the other fired the plane stalled and dropped. After several attempts it made one hit with a cannon shell, that was enough to stop that type of raid. That is what it was all about, it doesnt have to be "common" it would have persisted until a successful interception happened. This is what happened in the dog days of the BoB, what began as a free shot, dropping bombs randomly on Kent and London started to cost pilots and planes and so was stopped. Can you remind us what you said makes you cringe?

Here you are, my bold.
Quote "BoB got nowhere near 30000ft. Spitfire and 109E combat ceilings (1000fpm climb) were a little above 25000'. 110s about 21000ft. He111 ABSOLUTE ceiling was 22000ft. Nobody going near 30000ft, much less over except possibly recon missions. I cringe when I hear 30000ft in WWII.
 

We understand the difference.

As to your last statement, you're now trying to duck out of your incorrect statement without admitting you were wrong. You explicitly stated "BoB got nowhere near 30000ft." That's a pretty definitive statement. "Nowhere near" is not the same as "extremely uncommon."

You've been presented with actual pilot manuals citing that the Spitfire MkI and the Messerschmitt Bf109E-3 could get above 30,000ft. You have a contemporary account of a Spitfire pilot leading his squadron at 30,000ft and engaging Bf109s. And yet you persist that these data points are somehow not accurate?

Please provide data that you think is more accurate.
 
Depends on how the magazine defined operational ceiling. Was it service ceiling, combat ceiling, or something else. And all those planes came well after the BoB with ceilings well above the Spit I and 109E. And it was a magazine, not an official test.
 

So what about all the other data that's been presented related to Spitfire MkI and Bf109E-3. Are you going to ignore that as well?
 
Some of you guys (not all) need to understand the difference between service ceiling and combat ceiling.
Some people need to understand that there was also a 3rd ceiling, operational ceiling which was 500fpm, this was considered the climb rate needed for a small group of planes to maintain formation. The 109, Hurricane I and Spitifire I with constant speed props all had operational ceilings of over 30,000ft.
Source "The Merlin in Perspective-the combat years" 4th edition Rolls Royce Heritage trust. In Appendix V.
That's about as high as a fighter will want to go in combat.
There is also a difference between "combat" as in actual maneuver fighting and a combat patrol or flight in which the goal is to be above the enemy so they can use the advantage of height. The actual "combat" (firing of guns) may take place several thousand feet lower. Being the one's getting bounced from above was known not to be a good thing by about 1916
Would like to see those pilot manuals.
Try BELL P-39 AIRACOBRA - Flight Manuals
 
The important altitude is the altitude of the enemy aircraft coming into your space. Discussion of terms is just a distraction, as you know, that is why you are doing it.
 
Not uncommon? But they did not fight at 30,000ft? Okay, whatever you say. I just believe that in the BoB planes actually getting to 30000' is extremely rare, which I would define as a lot less than not uncommon. Extremely rare does not mean never. My opinion.

And I am not confusing combat ceiling with operational ceiling. I almost always reference combat ceiling as climb at 1000fpm.
 

From Spitfire Mk I K.9787 Trials Report

alt (ft) time (min) RoC (ft/min) 23,000 11.7 1135 26,000 14.8 790 28,000 17.8 555 30,000 22.4 325 32,000 32.9 95

Estimated absolute ceiling: 32,800ft
Greatest height reached: 32,400ft

That was with a fixed pitch wooden propeller (2 blade?).
 
Both sides in 1940-41 were working to improve the ceilings (all of them by whatever name) of their aircraft because it takes months if not years to get to get a new airplane or engine into service (variations of existing equipment takes less time but not instant), You can't wait for your opponent to show his improved capability. You have to be working on improving your own so you are ready when his improvement/s show up.
Reason for the Hurricane II was to improve the Hurricane so it was close to the Spitfire in capability so the total number of fighters being produced were altitude capable, making Spitfires with Merlin XX engines and continuing to make Hurricanes with Melrin IIIs or Melrin XIIs would have meant an overall less capable fighter force.
A wrench in the works was that cockpit heating, gun heating and oxygen equipment did not progress as fast as the engines so the engine improvements were harder to take advantage of.
The P-400/P-39 showed up at the wrong time. It showed up as the British were anticipating higher operational ceilings and the British were already getting low altitude P-40s and about to get low altitude Mustang Is.
In Mid 1941 to spring of 1942 the Bell fighter simply doesn't bring much to the table as production versions are much slower than promised and they can't do anything that can't be done by a number of fighters already in British service except complicate the supply situation.
 
AHT lists the 30calMG to have an effective range of 200yds in their gun table and talks about it in the text.

Yes there were lots of .30cal rounds available, since it was a standard round for the infantry. Are you advocating converting all seven guns in the P-39 to the .30cal? That makes about as much sense as your argument.

The .30cal MG was phased out of AAF/USN use before Pearl Harbor for all the American fighters except the P-39. I'm advocating it should have been phased out of the P-39 also.
 
Yes there were lots of .30cal rounds available, since it was a standard round for the infantry. Are you advocating converting all seven guns in the P-39 to the .30cal? That makes about as much sense as your argument.
Never said that did I?

Just saying that keeping the .30 cal was not the logistics problem you are making it out to be.

Now why don't you give the rest of the information in the tables and btw, the text includes NO definition of either "max effective practical range" or "max effective theoretical range"
For the .30 cal these ranges are the 200 yds you have said and 600yds, the 37mm cannon had ranges of 300yds and 600yds. The 50 cal has ranges of 300yds and 900 yds while the 20mm in the table has ranges of 1200 yds and 2400yds which is total nonsense.

I would also note that the heavier weight given for the 30 cal bullets like 220 grains is total nonsense. The US stopped putting 220 grain projectiles into 30 cal rifle ammo in 1906 when they changed from the .30-03 round to the .30-06. The .30-03 won't even chamber in a .30-06 gun.

AHT is very, very good. It is not infallible.

Have to go to work now.
 
Are you saying that a plane shot down at 30,000ft was not actually in combat because it was above the "combat" altitude? What do you call firing guns at each other, other than fight or combat? This is taking groundhogism to a new height, or dare I say a new altitude of semantics.
 
The .30cal MG was phased out of AAF/USN use before Pearl Harbor for all the American fighters except the P-39. I'm advocating it should have been phased out of the P-39 also.

As others have pointed out, the e0cal was still in use in P-40s at Pearl Harbor.

Also the 30cal was REPLACED with the 50 cal. So to match other US fighters, you'd have to do the same. How will that affect the weight of your P-39 wonder-weapon?
 
Uhh... are you saying now that the P-39 was able to do the Mustang's job? And is it supposed to match the Mustang's performance at 26,400 feet? Which is basically RIGHT in the Mustang's wheelhouse.

 

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