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3.JG51_BigBear
08-09-2007, 06:20 PM
Does anyone know how common the P-38L "Late" was in real life and when it entered service? Also, did the P-38L Late have the same enginge as the P-38L, tuned for greater performance, or did it have a different model of the Allison engine? Thanks

3.JG51_BigBear
08-09-2007, 06:20 PM
Does anyone know how common the P-38L "Late" was in real life and when it entered service? Also, did the P-38L Late have the same enginge as the P-38L, tuned for greater performance, or did it have a different model of the Allison engine? Thanks

berg417448
08-09-2007, 06:26 PM
I think it is just a P-38L with 150 octane fuel and higher boost.



P-38 total in ETO by month:

Jan 1945 562
Feb 1945 570
Mar 1945 625
Apr 1945 579
May 1945 555


*This total does not count the F-5 photo recon versions of the P-38. They are listed separately.

From USAF records: Airplanes on hand in Theaters vs Germany 1942-1945

http://www.au.af.mil/au/afhra/aafsd/aafsd_pdf/t088.pdf

3.JG51_BigBear
08-09-2007, 10:01 PM
Thanks for the info.

Still curious as to when they started "boosting" the lightnings.

Jaws2002
08-09-2007, 10:09 PM
Wasn't the boosted one used only in Pacific?

berg417448
08-09-2007, 10:10 PM
The Spring of 1944 was when it first began. Not sure when it became widespread.



In March 1944 the Allied Expeditionary Air Force (A.E.A.F.) decided, pending further trials, not to employ 150 Grade Fuel for Overlord due to spark plug issues, however, it was intended that 150 Grade would be used when proved satisfactory.6 Meanwhile, cross channel operations by two squadrons of P-47's and one P-38 using 150 Grade fuel revealed an increase of speed and climb characteristics at the expense of spark plug difficulties.7 Tests beginning in 20 March 1944 at Wright Field by the Army Air Forces Material Command of the P-51 B concluded:
There was no noticeable change in handling characteristics of any of the airplanes tested when operating at the higher powers which were obtainable with the 44-1 fuel. Only a slight increase in vibration was noted at the higher powers. On one long range test made with the P-51B, there was no apparent trouble due to the 44-1 fuel.
Approximately 16 MPH increases in speed below critical altitude and approximately 600 ft. per minute increase in rate of climb below critical altitude was obtained by using the 75" Hg. Manifold pressure allowed by 44-1 fuel. 8
Successful service tests led in May 1944 to the Eighth Air Force Fighter Command requesting that it "be supplied immediately with grade 150 aviation fuel for use in P-47, P-51 and P-38 planes". 9 Deliveries of Grade 100/150 aviation fuel to AAF Stations commenced within a week of the landings in France. 10

http://www.spitfireperformance.com/150grade/150-grade-fuel.html

csThor
08-09-2007, 10:15 PM
Wasn't the P-38 relegated to the 9th USAAF by the time 150oc fuel came into use? IIRC only the 8th USAAF and the GDBA (2nd TAF in 1945) received 150 grade fuel. http://forums.ubi.com/images/smilies/blink.gif

berg417448
08-09-2007, 10:35 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by csThor:
Wasn't the P-38 relegated to the 9th USAAF by the time 150oc fuel came into use? IIRC only the 8th USAAF and the GDBA (2nd TAF in 1945) received 150 grade fuel. http://forums.ubi.com/images/smilies/blink.gif </div></BLOCKQUOTE>

You are probably correct. There is another document on the spitfireperformance site that mentions that experience with 150 grade fuel in P-38 aircraft was limited due to replacement by P-51s.

AKA_TAGERT
08-09-2007, 10:52 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by 3.JG51_BigBear:
Does anyone know how common the P-38L "Late" was in real life and when it entered service? Also, did the P-38L Late have the same enginge as the P-38L, tuned for greater performance, or did it have a different model of the Allison engine? Thanks </div></BLOCKQUOTE>
150oct fuel had nothing to do with the P-38L LATE performance!

All P-38Ls were P-38L LATES!

The only dif being that initally they did NOT update the pilots manuals from the P38J stating they could NOT exceed 60MP @ 1600hp!

Even though pilots did it reguarly on the P38J prior to being told they could..

The P38J Allison engines needed 150oct to excced 1600hp to keep from pinging themselfs to death..

The P38L Allison engines were rated for 1720hp on 130oct fuel..

Oleg made the same mistake early P-38L pilots made when he made the P-38L..

He limited it to 1600hp!

After some fine folks here sent him some real world data showing the P-38L engines were rated for 1720hp he added in the P-38L LATE..

When in reality he should have just upgraded the P-38L to P-38L LATE performance..

But I guess he felt it necessary to capture that inital mistake that some pilots didnt realise they could exceed 1600hp.

Long story short

There is no such thing and a P-38L and P-38L LATE.

All L's were capable of doing what the L LATE could do.

Which is why any server that uses the P-38L instead of a P38L LATE is wrong!

Gibbage1
08-09-2007, 11:02 PM
The L "Late" is really just a normal L. The L's engine was rated at a higher boost then the J's, but Oleg programmed the L's engine with the same boost as the J. The L "Late" allows a higher boost then the L, but the L really had even a higher boost capacity then the "Late".

P-38J's max boost was 60" MP
P-38L's max boost was 72" MP
Pilots have told me that they had reached 83" MP when running from 109's.

3.JG51_BigBear
08-09-2007, 11:08 PM
Great info guys, thanks.