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SterlingX
05-15-2008, 10:11 AM
Played a bit offline to determine the shortest spin recovery for the P-39.
My record stands at recovery in 680m of altitude.
I challenge you to beat it http://forums.ubi.com/images/smilies/winky.gif

Track: P-39 N-1, 50% fuel, v4.08 (all realistic settings on)
http://www.datafilehost.com/download-9546dbce.html

TinyTim
05-15-2008, 10:21 AM
Flat spin?? If so, http://forums.ubi.com/images/smilies/11.gif. Could anyone of you good pals post a clip of it on youtube or somewhere, for us poor saps that don't have the sim installed atm?

SterlingX
05-15-2008, 10:29 AM
Er, no, normal spin - nose angle is oscillating around 50 deg to the horizontal. I turned at 0 power until I stalled and spun, then took immediate recovery action.

SeaFireLIV
05-15-2008, 10:39 AM
Now if it had been a recovery from a flat spin at 680m I would`ve been truly impressed!

...And asking for a track!

SterlingX
05-15-2008, 11:20 AM
Per popular demand, we bring you the second installment of the Cobra Spin Of Doom: Flat Spin.
Recovery from fully developed flat spin in 1000m alt.:
Behold!
http://www.datafilehost.com/download-80a222ab.html
/waited for flat spin to develop, took action at 1050m alt./

Any challengers http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif ?

TgD Thunderbolt56
05-15-2008, 11:24 AM
Originally posted by SterlingX:
Recovery from fully developed flat spin in 1000m alt.:
Behold!

Any challengers http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif ?


Nope. I've never flown one of those deathtraps. http://forums.ubi.com/images/smilies/shady.gif

SterlingX
05-15-2008, 11:32 AM
Originally posted by TgD Thunderbolt56:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by SterlingX:
Recovery from fully developed flat spin in 1000m alt.:
Behold!

Any challengers http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif ?


Nope. I've never flown one of those deathtraps. http://forums.ubi.com/images/smilies/shady.gif </div></BLOCKQUOTE>

Experience with the p-39 is actually quite rewarding, it's top notch online when flown right - it's my current fav.
Most of the time spins are avoidable, but since they do happen once in a while I decided to test for the best way to get out of those.
(those tracks are the result, I made the second track just now)

crucislancer
05-15-2008, 12:00 PM
Spin recovery in the P-39 is on my list of things to work on, I pretty much avoid that plane because of it. But, I agree it's a great plane, though.

Nicholaiovitch
05-15-2008, 01:50 PM
Hi ,
Would be very interested to see your ntrk but when downloaded gives me a php file extension. Can you put me wise as to get out of this spin also?
Have only ever managed to get out of a "flat spin" in this machine after using flaps and gear in addition to normal spin recovery and that seems to take forever. The direction of spin also has an effect as the engine torque can have a severe impact on recovery.
Thanks in advance.
Nicho http://forums.ubi.com/images/smilies/blink.gif

SterlingX
05-15-2008, 02:07 PM
It works on my computer - you click on the links, then it opens a page that says 'click here' (to download) (?)

x6BL_Brando
05-15-2008, 02:32 PM
Ctrl+E works most of the time http://forums.ubi.com/groupee_common/emoticons/icon_wink.gif

jarink
05-15-2008, 02:44 PM
Originally posted by x6BL_Brando:
Ctrl+E works most of the time http://forums.ubi.com/groupee_common/emoticons/icon_wink.gif

Yep, I find the parachute to be the most reliable spin recovery mechanism for me...
http://forums.ubi.com/images/smilies/touche.gif

TgD Thunderbolt56
05-15-2008, 02:45 PM
1. 0% throttle
2. Full down elevator
3. Full flaps
4. full opposite rudder to the spin

Am I close. http://forums.ubi.com/images/smilies/winky.gif

Honestly, the Cobra series has always been one of my favorite rides and if one is available in the planeset of whichever server I join, I'll take it. With enough altitude, flat spin recovery is always possible, but not guaranteed.

I consider myself a cobra "specialist", but not an "expert".

Nicholaiovitch
05-15-2008, 02:49 PM
Originally posted by SterlingX:
It works on my computer - you click on the links, then it opens a page that says 'click here' (to download) (?)

Hi again ,
Yup, I managed to download your file, but as I said, it is called "get.php"!! If it had a "ntrk" file extension I could watch it. I'm not too good with file extensions so basically I'm asking how to either "open" it or "convert" it?

Whilst we are at it, I think it would be very helpful if we could know all the details of your spin experiment. There are an awful lot of variables!
- Which P39 variant?
- How much fuel?
- What ordnance?
- What altitude did you start at? (density altitude has an impact)
- Left or right hand spin?

I think several guys like me would like to know if there is a way of getting this beast out of a genuine "flat spin" in minimum altitude.
Like I say, I have only managed it by lowering flaps to alter the "centre of pressure" and lowering the gear to give drag to avoid overspeed in the pull-out.
This is in addition to the normal spin recovery:-
- Full opposit rudder pause....
- Full down elevator
I have in addition tried the "pumping power" technique but even in a left hand spin with torque helping the recovery, she only seems to come out by lowering flaps and thus changing centre of pressure.
Even then, from a "flat spin", the recovery uses up several thousand feet.
Would be very interested to hear if anyone else has a better way. I'm afraid like most guys, I step onto the wing and say bye bye when it happens due to my over zeallous control inputs!
I would still like to see your movie if you can tell me how to install the file?
Nicho http://forums.ubi.com/images/smilies/compsmash.gif

DKoor
05-15-2008, 02:54 PM
Originally posted by TgD Thunderbolt56:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by SterlingX:
Recovery from fully developed flat spin in 1000m alt.:
Behold!

Any challengers http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif ?


Nope. I've never flown one of those deathtraps. http://forums.ubi.com/images/smilies/shady.gif </div></BLOCKQUOTE> http://forums.ubi.com/images/smilies/16x16_smiley-very-happy.gif

SterlingX
05-15-2008, 03:04 PM
Originally posted by TgD Thunderbolt56:

Am I close. http://forums.ubi.com/images/smilies/winky.gif



Also, gotta go to full throttle when the nose is lowest, preferably at a point in its oscillation when it's swinging down before swinging up again. Otherwise it won't recover at all. I also used gear down, but it didn't seem to make much of a difference, compared to sans-gear.

SterlingX
05-15-2008, 03:11 PM
@Nicho: left clicking all the way through might be the way to go, rather than right clicking and 'save as' (I can't help beyond that speculation)

Nicholaiovitch
05-15-2008, 04:17 PM
Originally posted by SterlingX:
@Nicho: left clicking all the way through might be the way to go, rather than right clicking and 'save as' (I can't help beyond that speculation)

http://forums.ubi.com/images/smilies/16x16_smiley-happy.gif At last, success! Don't know what I did but I got your ntrk.....

Watching it has of course answered many of the variables that I posted above except for "ordnance". Anyway, great track and I have replicated it several times:-

Interestingly, I thought for a moment that you had discovered a very unusual spin recovery trait for this machine by using "aileron" in the recovery (I see the stalled wing with down aileron....more drag!!) This is a no-no in all the types I have tried IRL, but I thought maybe it had helped?
Having tried your identical 1050m recovery and used "aileron" and "no aileron input" I find that the old premise (no aileron input)will extract the machine 200-250m higher than your recovery!! I did not use power either.
I cannot post a video yet, but I'm sure if you try the exact recovery below that you will pull out at 200-250m. above the ground (I think yours was at about 100m)
- Full left rudder...pause
- Full down elevator
- Full flap and gear (gear just to reduce speed and therefore height loss in the pull out)
- Zero power throughout.
NB. I selected 50% fuel but zero ordnance.

This is still nearly 3000ft from start of recovery....!
As has been said, it is a delightful machine if you are careful with it.
Great post "" and have enjoyed once again "exploring the envelope"
Nicho http://forums.ubi.com/images/smilies/clap.gif

Nicholaiovitch
05-15-2008, 05:08 PM
Hi ""

You can view my ntrk by clicking here:-SpinP39Nicho (http://www.datafilehost.com/download-ea71f4f9.html)
BFN
Nicho http://forums.ubi.com/images/smilies/16x16_smiley-happy.gif

DKoor
05-15-2008, 05:34 PM
Originally posted by SterlingX:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by TgD Thunderbolt56:

Am I close. http://forums.ubi.com/images/smilies/winky.gif



Also, gotta go to full throttle when the nose is lowest, preferably at a point in its oscillation when it's swinging down before swinging up again. Otherwise it won't recover at all. I also used gear down, but it didn't seem to make much of a difference, compared to sans-gear. </div></BLOCKQUOTE>+1

Anyone tried to use trim?
We can trim that nasty Cobra for perhaps, better results http://forums.ubi.com/images/smilies/winky.gif.

DKoor
05-15-2008, 06:31 PM
Managed to recover crate in 866m (http://www.datafilehost.com/download-9b6aea0a.html), second best 882m. 100% fuel, default armament, track version .TRK v4.08.
I think some of those stuff posted by you guys really works, and TBH it can be done even in a less altitude. At least I have this "feeling" http://forums.ubi.com/groupee_common/emoticons/icon_wink.gif . Anyhow can't be arsed for further recovering http://forums.ubi.com/groupee_common/emoticons/icon_razz.gif.

BTW awesome upload site, one must admit that http://forums.ubi.com/images/smilies/clap.gif. Nice 'n easy.

SeaFireLIV
05-15-2008, 06:54 PM
The P39 is a favourite of mine also. Apart from the Spitfire, I like flying planes that people consider cr@p or too hard to fly (like early planes), simply because everyone will rush for the `uber` planes like lemmings. Guess it`s my `be different` stubborn streak.

Anyway, the P39n1 is a great plane and most stalls can be kept to a minimum in combat or recovered. However, I simply don`t waste time trying to recover a flat spin once I get to 1000 metres cos after that chances are you won`t make it.

DKoor
05-15-2008, 07:05 PM
+1

Cobra stalls aren't all that nasty as they might seem... flat stalls are quite rare, at least in my experience. Most of those can be avoided...

TA-152 seems to be also one of the planes with nasty (flat) stall chars... also can be de-stalled flat for fun http://forums.ubi.com/groupee_common/emoticons/icon_cool.gif .

However... flat spin + combat damage is probably an one way ticket especially if they happen at low alt http://forums.ubi.com/groupee_common/emoticons/icon_frown.gif .

SterlingX
05-16-2008, 06:48 AM
Originally posted by Nicholaiovitch:
Hi ""

You can view my ntrk by clicking here:-SpinP39Nicho (http://www.datafilehost.com/download-ea71f4f9.html)
BFN
Nicho http://forums.ubi.com/images/smilies/16x16_smiley-happy.gif

http://forums.ubi.com/images/smilies/agreepost.gif

Interesting, no aileron and engine at idle (flaps and gear down as before) does seem to be the way to go.
Tested it a few times - it does produce consistent recoveries in about 800m.

OMK_Hand
05-18-2008, 03:21 PM
Hi.

It seems that applying full aileron in the direction of the spin speeds-up the recovery.

In a spin from 3000', recovery is possible in 2,500' (762m) by immediately:

Close throttle
Full flaps
Full opposite rudder
Full stick forward
Full stick in direction of spin.

Without the latter, one runs out of space and it's goodnight Vienna...

Don't know if air density plays a part?
From 10,000', recovery as above took 4,100' (to the point where I was no longer losing altitude).

From 6,000' the recovery took 3,600', and from 3,000' it took 2,500'.

Crimea map, full everything. P39 D1, 1941.

Matz0r
05-19-2008, 11:34 PM
Argh, I just had to http://forums.ubi.com/groupee_common/emoticons/icon_biggrin.gif

http://moya.pfy.nu/tmp/p39spin-w-ail.png

Spin recovery using 50% fuel and aileron.

Seems like recovery don't pick up until I push full elevator forward and aileron input slows me down initially, which would indicate less effective recovery. Will do one without aileron later http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif

DKoor
05-20-2008, 03:17 AM
Originally posted by F16_Matz_:
Argh, I just had to http://forums.ubi.com/groupee_common/emoticons/icon_biggrin.gif http://forums.ubi.com/images/smilies/35.gif

http://forums.ubi.com/images/smilies/88.gif

LovroSL
05-20-2008, 07:53 AM
P39 is a sweet ride (one of my overall fav <3) that engine in the middle reminds me of high end sports cars. It has an awsome gunsight for those high angle shots. It's kind of an Bf-109 with reduced maneuverability but more stable and less "jerky".

But it will kill you every now and then http://forums.ubi.com/images/smilies/784.gif


My rule of thumb- if you are not higher than 1500m just hit the silk.

BrotherVoodoo
05-20-2008, 08:26 AM
Originally posted by LovroSL:
P39 is a sweet ride (one of my overall fav <3) that engine in the middle reminds me of high end sports cars. It has an awsome gunsight for those high angle shots. It's kind of an Bf-109 with reduced maneuverability but more stable and less "jerky".

But it will kill you every now and then http://forums.ubi.com/images/smilies/784.gif


My rule of thumb- if you are not higher than 1500m just hit the silk.

http://forums.ubi.com/images/smilies/agreepost.gif

The P39 absolutley rocks. Great advise in these posts for flat spin recovery, thanks guys. I love the P39 even more now http://forums.ubi.com/images/smilies/inlove.gif

p51srule
05-20-2008, 10:15 AM
Ive never really had a problem with the P-39. I dont try to pull abrupt movement with many planes (exept the P-51 If moving at +250mph) Ive never been in a flat spin either but I think the best way to get out of it is to apply full opposit rudder, and point the nose down with 0% power.

P51srule http://forums.ubi.com/images/smilies/agreepost.gif

Nicholaiovitch
05-20-2008, 11:18 AM
[QUOTE]Originally posted by F16_Matz_:
Argh, I just had to http://forums.ubi.com/groupee_common/emoticons/icon_biggrin.gif

Interesting to see some science added to this post after everyone has tried it for real. http://forums.ubi.com/images/smilies/53.gif
Can't wait for your print out without aileron "MatZ" to see if what we found out so far is verified.
As for applying aileron "into the spin"?! Well, all I can think is that the drag of the "down going aileron" on the unstalled wing is providing some drag to slow the rotation down.
I'm not convinced that it will help though! Certainly not IRL.
IMHO the movement of the centre of pressure aft with the use of flap is what is lowereing the nose enough for the rudder to have airflow and thus stop the spin.
Fascinating anyway. http://forums.ubi.com/images/smilies/16x16_smiley-surprised.gif
Nicho

Swivet
05-20-2008, 12:20 PM
P-39: It was put into production before all the bugs were worked
out. And, yes, it certainly should have retained the turbo-supercharger it
was originally equipped with (which gave it a top speed of 390 mph at
20,000 ft when it was first flown in 1939, making it much faster than any
European fighter of that era). The P-63 was the aircraft the P-39 should
have been. The early versions of the P-39 were underpowered. The Q
version was actually quite good, performance-wise, but still suffered from
over-sensitive controls and the rearward movement of the center of gravity
once the nose ammo was expended. This made the plane susceptible to flat
spins. <span class="ev_code_YELLOW">Experienced pilots could handle it</span>. But most service pilots first
got their hands on a P-39 with less than 300 hours in their logbooks.
It was an easy plane to bail out of: merely jetison the door and roll
out. It was actually easier to bail out of that most other fighters.
That's not really saying very much. The chances of a successful bailout
averaged between one in four and one in two, regardless of aircraft type.
The chances of successful bailout varied based on the reason you had to
bail out, the attitude of the aircraft and its motion, and what the
altitude was. P-39s were notorious for killing their pilots because they
used an unreliable electric propeller that often ran wild. At altitude, no
problem. The pilot merely exited and floated to safety. But if it
happened at low altitude--and it seemed to happen most often when pilots
were practicing touch-and-goes in the landing pattern--the pilot usually
died. This was because the pilot tried to do something to bring the prop
under control, all the while losing altitude and airspeed. He often stayed
with the plane until it stalled and then it was too late. Veteran P-39
pilots got the hell out at the first sign of a runaway prop.

Bell P-39 Air Cobra (http://www.aviationshoppe.com/Bell-P39-Air-Cobra.html)

"Overall i think this little plane needs to be flown with great finesse without too many jerky movements, I am getting quite use to this trike, as i racked up 3 kills on it the othernight with some low level dogfighting. Managed to keep it fast and basically B-n-Z my targets and stroked her ever soo gently.."Whoa offtopic!, but i made it back to base http://forums.ubi.com/groupee_common/emoticons/icon_biggrin.gif"

OMK_Hand
05-20-2008, 01:35 PM
"Interestingly, I thought for a moment that you had discovered a very unusual spin recovery trait for this machine by using

"aileron" in the recovery (I see the stalled wing with down aileron....more drag!!) This is a no-no in all the types I have tried

IRL, but I thought maybe it had helped?"

"I'm not convinced that it will help though! Certainly not IRL."



Taken from Pilots flight operating instructions for the P-39Q-1 Airplane:

14. Spins.
Deliberate spinning is not recommended. However, if a spin occurs, rapid recovery can be made as follows:
a. PRERECOVERY.
1) Throttle must be off.

2) Propellor must be in low rpm position.

3) Stick full back.

b. RECOVERY.
1) Apply full opposite rudder when spin is at its slowest.

2) Wait until rudder effect is noticeable, then apply full forward stick and ailerons against the spin regardless of ammunition

load in the wings.

c. The spin is usually oscillatory in rate, and it is mandatory that the opposite rudder be applied when the spin is at its

slowest.

d. If the procedure above is followed, the airplane will recover in one-half turn. If the proceedure is not followed closely, the

airplane may not recover.



The game P39 spin recovery isn't at all accurate compared to RL, but certainly in RL opposite aileron as an aid to spin recovery wasn't unknown.


Also, from Republic P-47 operating instructions:

1) Full opposite rudder.

2) Neutral elevators.

3) Ailerons full against spin.



As to whether it helps in the game or not, just try entering a flat spin from straight and level at 3000' over the crimea sea, and compare a recovery with aileron into the spin to one without. That's the simplest (and wettest) way... http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif

Having said that, the flaps are definitely the key. They make it all possible...

Nicholaiovitch
05-21-2008, 01:59 AM
Taken from Pilots flight operating instructions for the P-39Q-1 Airplane:
etc. etc.


Also, from Republic P-47 operating instructions:

etc. etc.


Having said that, the flaps are definitely the key. They make it all possible...

-------------------------

That's so interesting OMK and thanks for finding that. http://forums.ubi.com/images/smilies/11.gif
I had a feeling that they must have explored all the "avenues" to try and guide the poor chaps to get out of this situation. I never knew that ailerons were used in so many types to get out of spins. I still do not understand the science behind it though!

Just one more thing......

How many of you guys "explore the envelope" in the types that you fly online before you drag them into combat?
I get the impression from some of the posts that some "hope they will never get into a spin"?
I have to say that it is what I find so interesting about flying a new type, and in any case I try and chose tropical waters for a warm swim on the first few attempts.
Nicho
http://forums.ubi.com/images/smilies/16x16_smiley-happy.gif