XP-39 II - The Groundhog Day Thread

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Please expand above.
 
I never said to remove any cannons, only the wing .30cal MGs. Only armor I recommend removing is the nose armor.
And I didn't say remove all guns just the cannons, the Spitfire didn't need nose armour it had an engine there, it needed armour behind the pilot and that was specified standard equipment.
 
Your point being?
The P-39 needed nose armour as a military machine, the Spitfire would certainly have been better in every way without cannon, speed climb and roll would have all been improved, but they were mainly concerned with those few seconds when the pilot presses the fire button, the reason it is called a fighter and not a Reno racer.

Quote"I believe the RAF flew one (1) mission and said "Nyet" and shipped them to the Soviets, ah but that's right, the Brits were in on the conspiracy to add weight to it and make it a dog. They certainly added a lot of weight that certainly wasn't needed, and that certainly affected its performance."
This (your bold), as I said, has been the issue from the start, you contend that the weight was not needed, but the RAF disagreed and the pilots who were relieved to switch to Spitfires that had that equipment on them did also.
 
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Weight was actually only reduced by 600+lbs which allowed the P-39K to fight at 27000'. Best Japanese bombers G4M came in at 18000'-22000'.

Yes, but it was suggested, (I can't make out exactly what the abbreviation given in the text is, due to the poor quality) that 1500 pounds could be stripped.
 
P-39 Expert,

There is not a 1,000 fpm climb difference between a P-39C and D, despite the test. For more than the 3rd time, there is something wrong with the P-39D test climb data. And the difference, whatever it is, is due to several factors, not just weight.

If you remove just nose armor, you move the CG aft. We already covered that. You could take off that way, sure. But, if you expended your ammunition, you might be a fatal danger, maybe not. Depends on what gets removed and the weight and balance of that partcular airplane.

Regardless of a sentence in a report, you can't remove 1,500 pounds from a P-39 and still have a fighter aircraft that flies, regardless of what the memo says. There isn't 1,500 pounds of stuff to be removed. There is only 193 pounds of armor including the windscreen glass. There is only 331 pounds of 30-cal guns and ammo. Where are you going to get the rest of your 1,500 pounds, huh?

You showed us a memo report on removing the wing 30's, but that was NOT a common practice, even in the South Pacific. While it might have worked for some specific missons at specific bases, it was not adopted widely. Let it go guy. The P-39, in these specific cases, didn't score a significant number of victories to get the practice noticed and emulated by anyone else.
 
P-39 did not need nose armor, Spitfire did not have armor for it's nose reduction gear, no other plane had armor for it's reduction gear. Bell theater tech reps never saw one instance where the nose armor was struck by an an enemy shell.
 
Expand above.
 
P-39 did not need nose armor, Spitfire did not have armor for it's nose reduction gear, no other plane had armor for it's reduction gear. Bell theater tech reps never saw one instance where the nose armor was struck by an an enemy shell.
Did the Bell tech reps check the P-39s that were shot down to see if the nose armour was struck by enemy shells? Aircraft that survive rarely have damage to vital parts
Beat me too it Fubar, in fact that was a branch of military statistical research. There is a "sampling error" here in that those who didn't return are not included causing "survivorship bias", it is actually a fairly convincing argument for more armour. Bullet Holes in Bombers: Operations Research and Management Science Applied to Marketing
 
The gearbox armor was 71 pounds out of 172 pounds of armor exculding the windscreen glass. If you add in the wing guns and wing gun ammuntion, that is only 503 pounds, not 1,500 pounds. Is there something you are missing here?

The empty weight of the P-39Q was 5,684 pounds. Then you add windscreen glass, armor, guns and ammunition, oil, fuel, pilot, and parachute. The total useful load was 1,886 pounds, guy, and the pilot was 200 pounds of the 1,886. Remove the pilot and you have 1,686 pounds of armor, guns, ammo, oil, and fuel. We need the oil. We need the fuel. If we don;t have guns and ammo, we might as well not take off. If we ditch ALL the armo, we only save 172 pounds.

Either you are not reading the weight and balance, not reading the posts, or are just being a troll.

Which is it? Help us out here. If you want to remove anything, identify it specifically. Please don't suggest leaving out the oil or fuel or pilot.

If I remove ALL the armor, I can take off just fine. But if I shoot all the ammunition, then I am out of CG aft, not good. Are you understanding this?
 
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Post #1346 Greg; it's not P-39Expert advocating removing 1500 pounds, it's from the USAF Historical Study no. 101 and is suggested by some presumably official organisation or command to Gen. Harmon.
As you point out, and why I brought up, is that it doesn't seem at all possible , from what I have read in this thread.
 
P-39: "P-39/P-400 vs A6M2/3 ZERO-SEN New Guinea 1942" by Michael John Claringbould
Somewhere in the depths of this thread FLYBOYJ posted a report by Lt. Col. Boyd Wagner, wherein he reported on the April 30 combat, and from his (and probably his pilots) perspective 4 Zeros were shot down (3 by Boyd, 1 by Greene), one Zero was actually lost. Boyd wrote that 3 P-39's were hit by Zero's and forcelamded due to cooling leaks, but all 3 pilots survived. Four P-39's were lost, Boyd makes no mention of Durand, who didn't return and remains MIA.
I reponded to the post here #261 with links to the fate of the respective planes and pilots on Pacific Wrecks.

To summarize, Pacific Wrecks has 1 forcelanded damaged by AAA (Andres), 1 sustained damage during combat and forcelanded (Brown); 1 short of fuel and likely lost, forcelanded (Bevlock); Durand last seen bailing out, MIA.

Claringbould has on p. 38, Andres as a focus, and writes that Andres (his own words) was chased by a Zero which he outran, but also ran short of fuel and bellied in18 miles SE of Buna.

On p.42-43, describing the combat, Claringbould has Andres forced to land due to damaged coolant system and both Brown and Bevlock forcelanding low on fuel. Andres was one of the few to witness Durands demise, but no mention of him bailing out.

So four differing versions, two from the same book.
 
Did the Bell tech reps check the P-39s that were shot down to see if the nose armour was struck by enemy shells? Aircraft that survive rarely have damage to vital parts
The only planes that they could check would be the ones that returned to base, right? They did not say that no nose armor had ever been struck, just that they had not seen one that had been struck.
 
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