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General Forums => Aces High General Discussion => Topic started by: eskimo2 on April 07, 2007, 03:46:12 AM

Title: P-39 & P-63 Stalls, Spins & Spin Recovery Procedure
Post by: eskimo2 on April 07, 2007, 03:46:12 AM
My father-in-law was a Flexible Gunner School Pilot Instructor at Indian Springs which was part
of the Army Air Force Western Training Command.  He primarily flew AT-6s, P-39s, P-63s &
 RP-63s.  Anyway, he still has his P-63 pilot’s manual, which I was thumbing through and noted
 the text on Stalls, Spins & Spin Recovery Procedure.  Both the Aircobra and Kingcobra were
famous for unrecoverable spins.   The P-39 and P-63 are very similar aircraft in balance, layout,
appearance and flying characteristics.  Here’s the scanned page on Stalls, Spins & Spin Recovery
Procedure.  (I’ve washed out the page and saved it as a monochrome GIF to get the filesize down
to 53 KB, it’s really not this black and white.)


(http://www.wwiirt.com/usaaf/william_wilsterman/p_63_manual_page_27.gif)

(http://www.wwiirt.com/usaaf/william_wilsterman/p_63_manual_front.jpg)

More about my father-in-law here. (http://www.wwiirt.com/usaaf/william_wilsterman/william_wilsterman.htm)
Title: P-39 & P-63 Stalls, Spins & Spin Recovery Procedure
Post by: moot on April 07, 2007, 04:51:21 AM
Why the limitation on inverted flying?
Title: P-39 & P-63 Stalls, Spins & Spin Recovery Procedure
Post by: straffo on April 07, 2007, 05:17:58 AM
The engine will lack oil, it's a common limitation (and who want to fly inverted for so long ?)
Title: P-39 & P-63 Stalls, Spins & Spin Recovery Procedure
Post by: Wilbus on April 07, 2007, 05:53:17 AM
Really, what did they expect other then bad stall and spin characteristics when they mounted the engine behind the cockpit?

Silly designers...
Title: P-39 & P-63 Stalls, Spins & Spin Recovery Procedure
Post by: TexInVa on April 07, 2007, 06:42:04 AM
Quote
Originally posted by Wilbus
Really, what did they expect other then bad stall and spin characteristics when they mounted the engine behind the cockpit?


A big gun.
Title: P-39 & P-63 Stalls, Spins & Spin Recovery Procedure
Post by: eskimo2 on April 07, 2007, 07:06:59 AM
Quote
Originally posted by Wilbus
Really, what did they expect other then bad stall and spin characteristics when they mounted the engine behind the cockpit?

Silly designers...


To fly, all planes have their CG in the same spot, typically 1/3 of the cord from the leading edge of the wing.  The P-39 and P-63 were not tail heavy.  One difference in these planes was that gained a little bit of nimbleness in having more of their mass near the center of the plane.  Much in the same way a mid engine car is a bit more nimble.


Now, if you want to talk about silly designers, there’s always the flying barrel:
(http://web.telia.com/~u52219934/216S29CF11-29-SAAB66-334.jpg)

;)
Title: P-39 & P-63 Stalls, Spins & Spin Recovery Procedure
Post by: Wilbus on April 07, 2007, 07:11:20 AM
Atleast that's a real plane :)
Title: P-39 & P-63 Stalls, Spins & Spin Recovery Procedure
Post by: IronDog on April 07, 2007, 07:32:26 AM
Thanx for  sharing.Makes one feel like they have stepped back in history for a brief moment.I had the chance to see a P63 fly several years ago.This P63 was nicely restored,and was once owned by an astronaut.I noticed the pilot didn't push the P63 as hard as he did the P51 he also flew,..."was Old Yeller by the way."Was really nice to see this special bird put thru it's paces.
IronDog
Title: P-39 & P-63 Stalls, Spins & Spin Recovery Procedure
Post by: Kweassa on April 07, 2007, 07:43:28 AM
Quote
Now, if you want to talk about silly designers, there's always the flying barrel:

(http://web.telia.com/~u52219934/216S29CF11-29-SAAB66-334.jpg)


 But.. but..  the 'barrel' was a significant design trend for early jet planes, which manifested itself in many excellent evolutionary cases such as this particular Yankee barrel;


(http://upload.wikimedia.org/wikipedia/commons/thumb/f/f1/North_American_F86-01.JPG/800px-)

 ..and this Russkie barrel..

(http://upload.wikimedia.org/wikipedia/en/thumb/5/5c/USAF_MiG-15.jpg/800px-USAF_MiG-15.jpg)


 ... which ofcourse, all had the common ancestry coming down from the father of all barrels, the Kraut barrel.. :D

(http://www.luft46.com/mrart/mr183-4.jpg)
Title: P-39 & P-63 Stalls, Spins & Spin Recovery Procedure
Post by: eskimo2 on April 07, 2007, 07:52:44 AM
Yea, but they are not as barrel chested as the SAAB.  Here's the original design concept:

http://hem.passagen.se/burrabee/72scale/mili.html
Title: P-39 & P-63 Stalls, Spins & Spin Recovery Procedure
Post by: Kweassa on April 07, 2007, 07:56:17 AM
arrrrgh... the dreaded "Red X" design concept!!

 :D
Title: P-39 & P-63 Stalls, Spins & Spin Recovery Procedure
Post by: eskimo2 on April 07, 2007, 07:58:23 AM
Quote
Originally posted by Kweassa
arrrrgh... the dreaded "Red X" design concept!!

 :D


OK, they won't let me hotlink.  Follow the new link, it's pretty funny.
Title: P-39 & P-63 Stalls, Spins & Spin Recovery Procedure
Post by: Wilbus on April 07, 2007, 08:50:10 AM
Hehehe, that was kind of funy ;)

Yup Kweassa, the ta 183 was the father of them all, however, I didn't dare say it as I'd be jumped by every yank on the forum (well almost) ;)

Oh btw, thanks for the spin/stall chart, always nice to see something from the original manuals.
Title: P-39 & P-63 Stalls, Spins & Spin Recovery Procedure
Post by: Simaril on April 07, 2007, 09:27:05 AM
Quote
Originally posted by Wilbus


Yup Kweassa, the ta 183 was the father of them all, however, I didn't dare say it as I'd be jumped by every yank on the forum (well almost) ;)

Oh btw, thanks for the spin/stall chart, always nice to see something from the original manuals.



Don't forget that design isnt done on a blank page. All those early designers started with the reality of a short fat jet engine.

And you expected the planes to look like what, exactly?

While German engineers were the first to cross many milestones, they didnt create the physics behind their designs. Much of it was simply engineering common sense, once you were given the parameters of what needed to be plugged in to the aircraft.





And any fair assessment of their engineering prowess needs to include the many outright silly sheets to leave their desks.
Title: P-39 & P-63 Stalls, Spins & Spin Recovery Procedure
Post by: moot on April 07, 2007, 09:32:08 AM
(http://marines.centreconnect.org/vmf_112/images/f4f_wildcat.gif)
Title: P-39 & P-63 Stalls, Spins & Spin Recovery Procedure
Post by: eskimo2 on April 07, 2007, 09:35:42 AM
Quote
Originally posted by moot
(http://marines.centreconnect.org/vmf_112/images/f4f_wildcat.gif)


Now there's just no excuse for that tubby thing!
Title: Re: P-39 & P-63 Stalls, Spins & Spin Recovery Procedure
Post by: Krusty on April 07, 2007, 06:33:56 PM
Quote
Originally posted by eskimo2
The P-39 and P-63 are very similar aircraft in balance, layout,
appearance and flying characteristics.



Not really. The P-39 had a lot more problems. Later versions tried to lessen them by installing more v-stab surface area, and even by reducing the prop blades from 4 to 3 to help reduce the instability.

The P-63 took all of these considerations and redesigned the entire shape of the aircraft to help reduce the instability.

P-39s would fly somewhat worse than P-63s because of this.
Title: Re: Re: P-39 & P-63 Stalls, Spins & Spin Recovery Procedure
Post by: eskimo2 on April 07, 2007, 07:19:45 PM
Quote
Originally posted by Krusty
Not really. The P-39 had a lot more problems. Later versions tried to lessen them by installing more v-stab surface area, and even by reducing the prop blades from 4 to 3 to help reduce the instability.

The P-63 took all of these considerations and redesigned the entire shape of the aircraft to help reduce the instability.

P-39s would fly somewhat worse than P-63s because of this.


Yea, I just asked him about this and he pretty much said that.  He said that they were instructed not to spin the P-63 and to absolutely never spin the P-39.  The Bell test pilots spun them and always recovered but apparently the Army didn’t think it was such a bright idea.
Title: P-39 & P-63 Stalls, Spins & Spin Recovery Procedure
Post by: Gianlupo on April 07, 2007, 07:25:51 PM
Excuse me, gents, but on behalf of italian national pride, I claim the honour for my country of having been the first one to build fat, barrel airplanes! :D

(http://blog.modernmechanix.com/mags/qf/c/ScienceAndMechanics/1-1933/lrg_flying_tunnel.jpg)

(http://images.auctionhelper.com/images/10343/Models/Caproni%20Stipa.bmp)

(http://p.airliners.net/photos/photos/9/2/5/1114529.jpg)

 (http://www.airbornegrafix.com/HistoricAircraft/ThingsWings/StipaCaproni.htm)

 (http://www.italiankits.it/doratistipa.html)

 (http://www.seqair.com/Hangar/Zuccoli/Legends/Legends.html)
Title: P-39 & P-63 Stalls, Spins & Spin Recovery Procedure
Post by: BaDkaRmA158Th on April 07, 2007, 08:56:51 PM
Wounder how it flew.
Title: P-39 & P-63 Stalls, Spins & Spin Recovery Procedure
Post by: Krusty on April 07, 2007, 09:04:13 PM
It's got wings, doesn't it??


P.S. LYNCH THE ITALIANS!!!! They've built craft designed by Satan! :t
Title: P-39 & P-63 Stalls, Spins & Spin Recovery Procedure
Post by: Brooke on April 08, 2007, 03:27:34 AM
Quote
Originally posted by Wilbus
Hehehe, that was kind of funy ;)

Yup Kweassa, the ta 183 was the father of them all, however, I didn't dare say it as I'd be jumped by every yank on the forum (well almost) ;)

Oh btw, thanks for the spin/stall chart, always nice to see something from the original manuals.


This reminds me of a great line in the film Ice Station Zebra, where Patrick McGoohan's character says, "The Russians put our camera made by our German scientists and your film made by your German scientists into their satellite made by their German scientists."
Title: P-39 & P-63 Stalls, Spins & Spin Recovery Procedure
Post by: TimRas on April 08, 2007, 03:35:44 AM
Stall recover procedure for P-39Q. It seems more difficult than in P-63.

(http://img.photobucket.com/albums/v424/timppa/P39stall.jpg)


From the "Pre-flight Curriculum for the P-39":
(http://img.photobucket.com/albums/v424/timppa/P391.jpg)
(http://img.photobucket.com/albums/v424/timppa/P392.jpg)
(http://img.photobucket.com/albums/v424/timppa/P393.jpg)
Title: P-39 & P-63 Stalls, Spins & Spin Recovery Procedure
Post by: Wilbus on April 08, 2007, 05:13:46 AM
Quote
Originally posted by Brooke
This reminds me of a great line in the film Ice Station Zebra, where Patrick McGoohan's character says, "The Russians put our camera made by our German scientists and your film made by your German scientists into their satellite made by their German scientists."


:rofl

I've seen the film but don't remember that line. So true though.
Title: P-39 & P-63 Stalls, Spins & Spin Recovery Procedure
Post by: Kweassa on April 08, 2007, 07:34:47 AM
My guess is this barrel obsession clearly demonstrates a German ancestry.

 It's a beer thing.
Title: P-39 & P-63 Stalls, Spins & Spin Recovery Procedure
Post by: Swoop73 on April 08, 2007, 10:19:19 AM
Wilbus.....The plane ballances just fine. Where they put the engine has nothing to do with the CG. The engine was back there to cut down on frontal area and to make it easy to stuff in the mother of all cannon. It was an idea worth trying. Most WW2 fighters and most fighters by definition are designed with the CG as far aft as they think they can get away with because this gives the lightest stick forces. The price you pay is usually poor spin recovery....Depending on what you consider poor.

Some pilots loved the design...Chuck Yeager and most of the Russians....Others didn't.

Swoop73
Title: P-39 & P-63 Stalls, Spins & Spin Recovery Procedure
Post by: Widewing on April 08, 2007, 11:06:10 AM
Quote
Originally posted by TimRas
Stall recover procedure for P-39Q. It seems more difficult than in P-63.


I don't think that there's much difference in the procedure. There is just a more explicit warning in the P-39 manual.

Many WWII fighters had nasty spin behavior, including the P-51 which frequently required 7,000 to 10,000 feet to recover.

Certainly, it won't be as difficult as trying to get the AH2 Mossy out of a flat spin.

By the way gents, the fastest way to get the Mossy out of a flat spin is to shut down the engines (not just pull power off to idle, but shut them off altogether).

I've been air spawning various aircraft at 30k to test spin recovery. When air spawned, the mossy immediately enters a flat spin (you cannot prevent it). The fastest way to recover is to not start the engines... She will nose over all by herself. If you do start the engines, you'll just have to shut them off.

My regards,

Widewing