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

[Snautzer01]

The P-39 does have beautiful plumage though.

Yes but it keeps pining for the fjords.

 

[Peter Gunn]

I almost hate to chime in on this thread anymore but smart decisions are not my forte.

RE: 37mm cannon.

Waaaay back in the dark ages of the 1970's when I was still in GA and was the dumb kid working at the airport I knew a fellow that would come out every so often to fly. He had been an actual honest to Yeager P-39 pilot in the SWP. The one tidbit I remember was how much he disliked the 37mm cannon for anything other than landscaping. The trajectory was terrible he said, like a rainbow. It fired too slow and he couldn't hit anything with it in the air, he did however favor it for shooting up Japanese barges and small craft on the water. He related that one time he put a 37mm round into a barge carrying troops, he said it rattled around like a pinball in a bathtub and made a real mess. It was one of the times he threw up in the cockpit. I can only imagine what that did to human flesh and bone... ugh.

I see a lot of balloon juice here about how magnificent the 37 was for firepower, strange that a real pilot who flew it in combat did not think so. I'm sure someone will be happy to refute this with a chart or a graph or some such drivel showing how wrong my old friend was.

Fortunately he survived his time in the P-39 (his words btw) and his next assignment to a front line squadron was with his true love, the Cadillac of the Skies.

Also, regarding another post up thread, the air war was won by the time the P-51D arrived? News to me.

Also regarding the P-39 being a "beast down low", I think Buzz Wagner would disagree with you.

 

[GregP]

Our new logo:

The angry Platypus - "We are Platypus! Resistance is futile! We saw what you did and we know who you are! An avenging 5,500-pound P-39 without nose armor shall wipe you from the face of the Earth and it will do the job better than any other airplane in the inventory!"

 

[SaparotRob]

I bow down before The Mighty Platypus.

 

[GregP]

Well .... OK... but don't let it happen again! ... and another thing, get rid of that pesky nose armor!

 

[GregP]

Wait ... this is a joke, right?

"Get out of the way, you billigan!"

If you squeeze the airplane to make it shorter, the CG will still be aft of limit, but not nearly as far aft of limit as it was before being squeezed, so it should fly better than before. Or something like that. And, if you painted a swastika on it, it would beat everything else in the sky! Then, BOTH sides would be flying P-39s! The one with the swastika would win, right?

 

[fubar57]

That's how you sort out the CoG

 

[SaparotRob]

The things one learns here.

 

[P-39 Expert]

Quite right, a hit assuming there is one will ruin your day. '
How good is your day if you are hit by 16 20mm shells?
Difference in the rate of fire of the 37mm and four 20mm Hispano guns.
The Hispano guns, being higher velocity, are easier to hit with.

P-39s could NOT do interceptions at high altitude either.

I am comparing the P-39M (nov 1942) to the Typhoon (Nov 1942) not seeing the Beast.
P-39M does 345mph at 2750ft using 57in of Map and 322mph using military power. Typhoon does 349.5 at 2000ft and 357.5 at 4,000ft. using 7lbs of boost.

Use the N.

 

[P-39 Expert]

From the web site you quoted

August 1943.
Cleaning up.
The remaining cleaning up modifications are now on the production machine. (I think we can agree that this was the standard production version of the Typhoon for the war in Europe, post invasion)

These are(a) Exhaust shrouds.(b) Whip aerial(c) Sliding hood.
Tests at Gloster on a repaired aircraft with a whip aerial and sliding hood fitted have given the following level speeds corrected on the basis of A. & A.E.E. Res.170.
M.S. M.P.A 398 m.p.h. at 8,800ft F.S. M.P.A 417 m.p.h. at 20,500ft.

Note - I also notice that you don't disagree with my comments on the Payload carried by the Typhoon, its much better armour and general firepower.

So when did this cleaned up Typhoon actually enter combat?

 

[P-39 Expert]

I do know that, but you continue to try to use issues like this to justify most of your arguments. And again, if you take weight out of the nose by installing a lighter cannon you're making matters worse! If you want, I'll do a weight balance calculation with a 20 mm cannon and remove the gear box armor.

This tells me that the P-400 probably had ballast in the nose along with that (drumroll) gear box armor!

BTW - You "balance" on a see-saw, you "balance" on a tight rope, you get an airplane in "Center of Gravity Range" or C/G.

I agree with you, but this just proves Bell could ballast the plane to stay in its CG envelope.

 

[GregP]

Is this the C.G envelope we are talking about?

 

[FLYBOYJ]

I agree with you, but this just proves Bell could ballast the plane to stay in its CG envelope.

And ballast is sometimes necessary EXTRA weight needed to make the aircraft fly better if at all!! The same as leaving the GB armor installed!!!! Again, why do you think the Soviets did not remove this!!!

Something posted earlier about the P-63...

In February 1944, the Soviet government sent a highly experienced test pilot, Andrey G. Kochetkov, and an aviation engineer, Fyodor P. Suprun, to the Bell factories to participate in the development of the first production variant, the P-63A. Initially ignored by Bell engineers, Kochetkov's expert testing of the machine's spin characteristics (which led to airframe buckling) eventually led to a significant Soviet role in the development. After flat spin recovery proved impossible, and upon Kochetkov's making a final recommendation that pilots should bail out upon entering such a spin, he received a commendation from the Irving Parachute Company. The Kingcobra's maximum aft CG was moved forward to facilitate recovery from spins.

Most significantly, Soviet input resulted in moving the main cannon forward, favorably changing the center of gravity, and increasing its ammo load from 30 to 58 rounds for the A-9 variant.

Gordon, Yefim. Soviet Air Power in World War 2. pp 450–451
Dean, Francis H. America's Hundred Thousand pp 410, 602

 

[BiffF15]

Interesting points FBJ. The number 1 customer goes to the manufacturer, is initially ignored, but later proves his point to such an extent that changes are made (moving the CG FORWARD) of version 2.0 of the Cobra. With all that Bell knew about the P-39 it's interesting to see what they initially got wrong on the P-63. It's almost as if they thought they were smarter than the user. And looking at Bell through that perspective might give one pause.

Cheers,
Biff

 

[FLYBOYJ]

Interesting points FBJ. The number 1 customer goes to the manufacturer, is initially ignored, but later proves his point to such an extent that changes are made (moving the CG FORWARD) of version 2.0 of the Cobra. With all that Bell knew about the P-39 it's interesting to see what they initially got wrong on the P-63. It's almost as if they thought they were smarter than the user. And looking at Bell through that perspective might give one pause.

Cheers,
Biff

Thanks Biff - but OH, LOOKIE HERE!!!

"The weight distribution of the P-39 was supposedly the reason for its tendency to enter a dangerous flat spin, a characteristic Soviet test pilots were able to demonstrate to the skeptical manufacturer who had been unable to reproduce the effect. After extensive tests, it was determined the spin could only be induced if the aircraft was improperly loaded, with no ammunition in the front compartment. The flight manual noted a need to ballast the front ammunition compartment with the appropriate weight of shell casings to achieve a reasonable center of gravity."

Dean, Francis H. America's Hundred Thousand P 200

So with that said, do you think anyone in their right mind would want to remove the 70 pounds of armor from the gear box????

 

[pbehn]

And ballast is sometimes necessary EXTRA weight needed to make the aircraft fly better if at all!! The same as leaving the GB armor installed!!!! Again, why do you think the Soviets did not remove this!!!

Something posted earlier about the P-63...

In February 1944, the Soviet government sent a highly experienced test pilot, Andrey G. Kochetkov, and an aviation engineer, Fyodor P. Suprun, to the Bell factories to participate in the development of the first production variant, the P-63A. Initially ignored by Bell engineers, Kochetkov's expert testing of the machine's spin characteristics (which led to airframe buckling) eventually led to a significant Soviet role in the development. After flat spin recovery proved impossible, and upon Kochetkov's making a final recommendation that pilots should bail out upon entering such a spin, he received a commendation from the Irving Parachute Company. The Kingcobra's maximum aft CG was moved forward to facilitate recovery from spins.

Most significantly, Soviet input resulted in moving the main cannon forward, favorably changing the center of gravity, and increasing its ammo load from 30 to 58 rounds for the A-9 variant.

Gordon, Yefim. Soviet Air Power in World War 2. pp 450–451
Dean, Francis H. America's Hundred Thousand pp 410, 602

So after 5 years the operator is still telling the designer and constructor how to sort it out?

 

[FLYBOYJ]

So after 5 years the operator is still telling the designer and constructor how to sort it out?

And this is one of the reasons why, IMO, Bell Aircraft ceased to be a major player in providing the US government with fighter aircraft in the post war years.

 

[GregP]

Only a Groundhog Platypus would remove the armor.

 

[pbehn]

Only a Groundhog Platypus would remove the armor.

I didnt realise how much Monty Platypus humour was influenced by the P-39, until I saw this thread.

 

[P-39 Expert]

And this is one of the reasons why, IMO, Bell Aircraft ceased to be a major player in providing the US government with fighter aircraft in the post war years.

That's odd, isn't Bell still to this day supplying aircraft to all four services?