P-38 Driving questions...

[AcesGun]

A nice little write up about the advantages and disadvantages of the P-38L, especialy for Aces high.

All credit to the guy that wrote this.

P-38L Overview

[Soda]

Soda's Aircraft Evaluations

Glad you found my site useful and I try to keep it up to date when I have the time.

I found the comparision of ideas in this thread interesting since I know how good some of the guys who have commented in this thread are.

-Soda
Aces High Trainer Corps
The Assassins.

[Ack-Ack]

Originally posted by Soda
Soda's Aircraft Evaluations

Glad you found my site useful and I try to keep it up to date when I have the time.

I found the comparision of ideas in this thread interesting since I know how good some of the guys who have commented in this thread are.

-Soda
Aces High Trainer Corps
The Assassins.

Some minor errors in the P-38L evaluation write up.  Flaps can be deployed at 250mph (IAS) or lower and the description for compressability is incorrect and compressability in the P-38 only occured in dives if they were started above 20,000ft, not at any altitude.


Ack-Ack

[Soda]

I actually have a revised P-38 page to put up but Ack-Ack is correct, flaps can be used up to 250mph.  

Compression can occur at any altitude though at lower altitudes the critical number is higher (right around 500mph).  At higher levels this is lower, more in the range of 460mph.  You also tend to see Mach buffet before compression and also structural creaking at lower levels.  It is entirely possible in an extended shallow dive to compress all the way to the ground though.  Recovery at lower levels is much easier, simply throttle back and bleed a little speed.  The P-38 doesn't seem to "run-away" in compression nearly as badly as the 109's do.

-Soda
Aces High Trainer Corps
The Assassins.

[Ack-Ack]

Originally posted by Soda
I actually have a revised P-38 page to put up but Ack-Ack is correct, flaps can be used up to 250mph.  

Compression can occur at any altitude though at lower altitudes the critical number is higher (right around 500mph).  At higher levels this is lower, more in the range of 460mph.  You also tend to see Mach buffet before compression and also structural creaking at lower levels.  It is entirely possible in an extended shallow dive to compress all the way to the ground though.  Recovery at lower levels is much easier, simply throttle back and bleed a little speed.  The P-38 doesn't seem to "run-away" in compression nearly as badly as the 109's do.

-Soda
Aces High Trainer Corps
The Assassins.

Here is a good write-up from the web site P-38 Online about the effects of a dive in a P-38 and why you should be more wary of compressability at high altitudes than you should at lower altitudes.

A typical dive of the P-38 from high altitudes would always experience compressibility. Starting from 36,000 ft., the P-38 would rapidly approach the Mach .675 (445 mph true airspeed). At this point, the airflow going over the wing exceeds Mach 1. A shockwave is created, thus breaking up the airflow equaling a loss of lift. The shockwave destroys the pressure difference between the upper and lower wing, and disrupts the ability for the aircraft to sustain flight. As the lift decreases, the airflow moving back from the wing also changes in its form and pattern. Normal downwash aft of the wing towards the tail begins to deteriorate. The airflow across the tail shifts from normal to a condition where there is now a greater upload, of lifting force, on the tail itself. With the greater uploading force applied to the tail, the nose of the aircraft wants to nose down even more, which creates a steeper and faster dive. As the aircraft approaches the vertical line, it begins to tuck under and starts a high-speed outside loop. At this point, the airframe is at the greatest point of structural failure. When the angle of attack increases during the dive, it also increases for the tail. The resulting effect is that the pilot cannot move the controls because tremendous force is required to operate the aircraft. The pilot is simply a passenger during this period. Shockwaves become shock fronts, which decrease the lift no matter what the pilot tries to do. Instead of smooth airflow over the wing, it is extremely turbulent, and strikes the tail with great force. The aircraft can only recover when it enters lower, denser atmosphere lower to the ground.

The solution to the problem was in understanding that the speed of sound changes with the altitude. At sea level, it is 764 mph, while at 36,000 ft. it is 660 mph. An aircraft moving at 540 mph at 36,000 ft. is much higher in the compressibility zone. The same speed at sea level results in the aircraft being exposed to lower effects of compressibility, and will respond to pilot controls. The dive recovery flap was a solution to this problem. In the ETO, German pilots would dive out of trouble because they knew the P-38 pilots would not follow. This greatly reduced the effectiveness of the aircraft in normal battle conditions. The NACA tested the flaps in high-speed wind tunnels at the Ames Laboratory. They tried several locations before discovering that when the flaps were positioned just aft of the trailing edge of the wings, it showed definite improvements. The flaps were finally positioned beneath the wings outboard of the booms, and just aft of the main structural beam. The pilots had a button on the yoke, and would simply activate the flap just prior to entering a dive.

P-38 Online



 Ack-Ack

[OIO]

There's one thing soda, the 38's flaps dont give the plane any real advantage unless its got 2 or more flaps out. The 1st flap only helps at alts above 25k, below that it only slows the plane down without giving it any serious turn performance.

And thanks to the $#@#$ bs autoretracting flaps in AH, the 38 cannot use 2 flaps during a fight for long because the INSTANT the speed ticker hits the 200mph mark, it retracts, making the plane extremely unstable and spin-happy, especially if you are pulling G's (which is the only reason why you have the damn flaps out in the first place, to TURN).

There's nothing more frustrating in this game than baiting a high E/Alt con into sciscoring or turning/looping with you, be pulling 3G's constantly, your speed be 180mph, 2 or 3 flaps out, you're gaining angles on the con on a below horizon turn/loop/sciscor portion, speed goes 180 ... 190..185..200 *WRUMMMM* flaps start retracting, speed is 190 ... All because it hit the 200 mark for a split second and the 38 loses angles inmediately, and god help you if you were actually beggining to pull a bit harder on the stick when it was retracting because it will spin the plane instantly.

A load of crock if you ask me. Bah!

[DAVENRINO]

OIO,
Maybe you would prefer the structural failure that probably began to occur at 200 in RL.

Doctor, it hurts when I do that.

Don't do that.

DJ229

[OIO]

No, structural failure/problems occured at around 300mph. Early model 38's used their flaps above 250mph (with severe buffetting); it was only the late models (J, L) that had locks to prevent their DEPLOYMENT above 200mph (which was a pencilneck assigned safety airspeed).

The 38's fowler flaps could not be blown "up" by the windforce because of the flaps mechanical deploy/retract system (if memory serves me right it used a railing system.. Widewing and BodhiArm can provide more info on this).

IMO, if HTC willing, the P-38L should not deploy flaps above 200mph, but if they are deployed they should not autoretract.

Instead, make them seriously buffet the plane when they are deployed 50 mph above their historic speeds (aka, real 38s could deploy their flaps out to 250 mph with little or no issues), and RIP out at 100 mph above said speed.

That way you can have a 38L with 1 flap out with no issues out to 250 mph, from 250 to 300 it should shake the 38 so bad as to mimic compression, above 300 they should rip out.

2 flaps can be out from 180mph to 230mph with no probs, 230->280 have it shake like Fatty on a nudy bar, above 280 rip them out.

and so on.

And this is *required* imo, for the P-38, which is the one plane in the whole set which depends on its flaps for its combat performance.

[DAVENRINO]

Good info,
I wasn't aware of that.  I just assumed HTC had a valid reason for the auto-retract.   I doubt that any WW2 planes actually had auto-retract flaps.  Modern planes with this feature actually use computers and servos rather than windforce.
DJ229 - AIR MAFIA

[Ack-Ack]

Originally posted by DAVENRINO
Good info,
 I doubt that any WW2 planes actually had auto-retract flaps.  
DJ229 - AIR MAFIA

Some WW2 planes had that feature.  Don't know which American or Allied planes used them but I'm pretty sure some of the Axis planes had some sort of auto-retracting flap system.  IIRC, the N1K2 was one of those planes.


Ack-Ack

[Pooh21]

Ok been flying P38 last few days fun as hell turning inside niks and spits and knocking la7s out of the sky with ease. Last night just for the hell of it I decided to stay on a lone spits 6 as long as I could followed everyturn and roll before I killed him. Yet the next few sorties I cant outfly a friggen p47d11? Does a P47d11 with a missing left flap actually hold advantage over p38 in 200mph rolling scissors?

[OIO]

you gotta show me how you handle n1ks then. I just HO them and dive away, those UFO flight model dweebrides are not worth the aggravation.

P-47s, ANY p47, is really dangerous in the first set of sciscors, and its because of its awesome rudder control. Its like a 109 really, the P38's rudder is half as good as those 2 planes, so the real trick is to use the 38's superior drag to not let the p47/109 sciscor behind you. In short, put them flaps out and cut the engine, pull up hard as you can with as much rudder as you can and always go for "lead persuit" (aka your nose in front of enemy plane, so you pull more G's than he does).

I believe I shot you down in my P-51D last night pooh, if that was you, you doing great! With me having massive E advantage you managed to almost get me on the zoom up.. i saw the tracers fly by me. You wouldve gotten me if you had sprayed a bit more, remember you have 2000 rnds of luving in that kite

[Z0mBe]

Thanks everyone for even more great tips.  Unfortunately, on Thursday morning lightning killed my computer, scanner, and joystick.  My insurance will cover the repair/replacement, but it still sucks for the time being.

I am going to try to salvage the hard drive so hopefully all my settings will not be lost.  

I have a MS sidewinder precision pro.  Anyone have any tips on a new stick?  I like twisty rudder controls .

See you all in the air.

<>

Z0mBe

[mia389]

Zombe that what I use and I love it. if you would like I can send you my whole settings folder. and my sights folder. See if you like them and all my head pos. and my sights,convergances. Only thing is my key mapping is changed a tad bit, so I could use diff. engines other than apply power to both. On my stick I have flaps up and down, trim up and down,dive break and wep, primary and secondary guns. If would like my settings I will send them.

[BOOT]

Same Stick here mia...
Could you send me a copy of the sights and Head positions ?
Thanks

BOOT@327th.com