Author Topic: P-38L What can we expect at high alt?  (Read 397 times)

Offline Yeager

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P-38L What can we expect at high alt?
« on: February 25, 2000, 05:15:00 PM »
The 38L being a late version, what can we expect in terms of high altitude performance
starting at 15k and going up past 30k?

Yeager
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Offline Westy

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P-38L What can we expect at high alt?
« Reply #1 on: February 25, 2000, 05:35:00 PM »
 Hmmm!!! Is the tail warning radar, that the "L" had, being modelled????  

 Here is the handiest link with info on the P-38 "L"

 http://home.att.net/~jbaugher1/p38_15.html

For reading that is more interesting head to here: http://home.att.net/~C.C.Jordan/index.html
and you can read several decent articles on the P-38 aircraft in combat.
 
-Westy



[This message has been edited by Westy (edited 02-25-2000).]

Citabr

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P-38L What can we expect at high alt?
« Reply #2 on: February 25, 2000, 05:35:00 PM »
and what of the low speed and stall characteristics?


Citabr

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P-38L What can we expect at high alt?
« Reply #3 on: February 25, 2000, 05:52:00 PM »
this could be interesting reading for any would be flight model designers  

 
 http://www.airpoweronline.com/wings/w.april90.html

Offline Wardog

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P-38L What can we expect at high alt?
« Reply #4 on: February 25, 2000, 06:42:00 PM »
Performance and speed of the H,J & L models are all very close.

Max Speed: (H,J,L) 391-414mph
Initial Climb: 2,850ft per min
Service Ceiling: (H,J,L) 44,000ft

The early YP38s where equiped with 37mm Oldsmobile Cannon



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Offline Minotaur

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P-38L What can we expect at high alt?
« Reply #5 on: February 25, 2000, 09:59:00 PM »
Concernary Note:  User might experience slightly extended load times.  Don't whine, get more bandwidth!  

The Forked Tailed Devil

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Offline Minotaur

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P-38L What can we expect at high alt?
« Reply #6 on: February 25, 2000, 10:06:00 PM »
Wardog;

Check my posting under "The Forked Tailed Devil".  There is a chart showing performance, middle of the way down in the thread.

Initial climb to 5000ft is 3200fpm @ 17400lbms GTW

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Offline Fishu

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P-38L What can we expect at high alt?
« Reply #7 on: February 26, 2000, 10:45:00 AM »
I wonder if they are ever going to add engine freezing into AH..

Engine freezing at higher altitudes (+20k?) was one of the weak sides for earlier P-38s (before L).

Offline juzz

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P-38L What can we expect at high alt?
« Reply #8 on: February 26, 2000, 10:59:00 PM »
The J fixed the engine overheating problems that earlier model Lightnings experienced.

Offline Fishu

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P-38L What can we expect at high alt?
« Reply #9 on: February 27, 2000, 06:38:00 AM »
 
Quote
Originally posted by juzz:
The J fixed the engine overheating problems that earlier model Lightnings experienced.

But how about freezing?
Earlier B-17 models had also freezing problems at higher altitudes.
B-17E had alot of those problems, F had some fixed and G finally flew without freezing problems.

I Have read about P-38s having same problem until L came.

funked

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P-38L What can we expect at high alt?
« Reply #10 on: February 27, 2000, 08:13:00 AM »
Yeager, some info from America's Hundred Thousand:

P-38L engines were V-1710-75/77 and V-1710-111/113.  Combat Power of 1,600 hp at 60" Hg was available all the way from sea level up to 28,700 feet.  Normal Power of 1,100 hp at 44" Hg was available up to 33,800 feet.

Rate of climb was about 3,400 fpm at 15,000 feet falling off to 2,000 fpm at 30,000 feet.  

Speed at 15,000 feet was about 395 mph, increasing to 420 mph at 25,000 feet then falling off to about 410 mph at 30,000 feet.

These are all excellent figures, particularly the climb rate.  Compared to other planes, the decline in performance at 30,000 feet was not large at all.

Offline Gator

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P-38L What can we expect at high alt?
« Reply #11 on: February 27, 2000, 01:33:00 PM »
Fishu writes: "Engine freezing at higher altitudes (+20k?) was one of the weak sides for earlier P-38s (before L)." and "I Have read about P-38s having same problem until L came."

  Fishu, I don't recall from my reading that there was an engine freezing problem with the P-38, if you have a reference handy I would appreciate it if you would look it up for me.

  Like Juzz says, primary focus for the engines on the earlier models seemed to be overheating problems caused by high performance demands and the turbo-superchargers.  The frigid temperatures at altitude are actually credited with helping with WEP/WER on the earlier P-38's.

  That having been said, there is mention by Martin Caidin (Fork-Tailed Devil: The P-38) that to increase reliability at high altitude the mechanics, as a temporary fix, blocked off oil cooling radiators to raise the temperature of the engine oil and improve lubrication on the earlier P-38's.  Automatically operated oil radiator flaps were introduced during the H's production run, and field modification kits were also produced.  FWIW, I read that the 55th Fighter Group's P-38H's during the winter of '43 were reported to have a tendency to consume oil above 22,000 feet.

  The main problems at altitude with the pre-J's seemed to be:
  • Bitterly cold cockpits and canopy defrosting problems.
  • In the ETO, engine and turbo-supercharger problems at high altitude (around 30,000 feet).  It appears that most analysis places the blame on the "poor quality British fuels", which "proved unsuitable for use in turbo-supercharged inline engines.  Powerplants with two-speed, two-stage, mechanical superchargers, and even radial engines with turbo-superchargers did not have the same ingestive problems with the British fuels" (P-38 Lightning, Part 1, XP-38 through P-38H, D&S Vol. 57, Bert Kinzey).

  • Thick contrails caused by the turbo-superchargers marking their location, and hindering their operations (frustrating the pilots since the Germans could spot the Lightnings at greater distances, and only engaged when they had an advantage).  There is brief mention that "the turbo-superchargers suffered from interference by frozen vapor trail condensation" (Warbird Tech Series, Vol. 2, Lockheed P-38 Lightning, Frederick Johnsen), but perhaps the attention given by the mechanics to reduce the thick contrail also addressed this "interference".
[This message has been edited by Gator (edited 02-27-2000).]

Offline Minotaur

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P-38L What can we expect at high alt?
« Reply #12 on: February 27, 2000, 02:26:00 PM »
I believe the P-38 also had electric constant speed propeller mechanisms.  If the mechanism lost power, it would over speed the engine.



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