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Lockheed P-38G-1


It does seem like its slightly under-performing in game for some suspicious reason...

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If someone can find turn / roll / stall data, it would be great !

 

The main problem of theP-38 right now is that everything is not performing according to the common opinion, but climb rate is the smaller problem

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[spoiler]

Looks good, this is at full fuel right?

 

Bar the WEP issues most of problem people are having with this aircraft is with its control surfaces, which at almost all speeds are quite uncharacteristically unresponsive.

 

Also which G series is this?

 

Here's a P38G-10 at almost 3800 fpm max at 14720 lbs and less than 3 mins to 10,000 feet probably around 270-300 gal of fuel.

P-38G-10-chart-1400.jpg

 

 

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

 

And here's a G-1 climbing at 3660fpm max at 13900 lbs with a little bit better flight time to 10,000 ft at 2.81 min with exactly 180 gal of fuel.

 

http://www.wwiiaircraftperformance.org/p-38/P-38G-1_42-12687_FS-M-19-1538-A.pdf

 

Both are early - mid 1943 aircraft.

[/spoiler]

Previous data no longer relavant.

 

On the other hand, can we please have WEP on this aircraft? The P38G was ran at 60 Ins. Hg. (1,600 lhp) and 70 Ins. Hg. (1,700hp) by their crews after stress tests by Ben Kelsey and Colonel Cass Hough proved that the P38s could handle higher CATs of uppwards of 70 degrees C, the P38G can operate in these conditions for at least 5-8 minutes without any harm.

Edited by SnafuSnafu
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Sources:
1. 3589 01-75FG-2 Handbook of service instructions (British air publication) for the Lighning I Aeroplane
http://www.avialogs.com/viewer/avialogs-documentviewer.php?id=3589

 

 

This source can be discarded as it was for the export Lightning I.    It did not include superchargers nor did it have counter rotating engines.    It was the "Castrated" Lightning and after the British refused the order; they were then used for training only.

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http://www.scribd.com  has tons of documents on the P-38 and books.    Most you probably have though,  the type of information you guys are looking for is darn near a needle in a haystack (that might not even exist) and I don't envy anyone on that.

 

One thing that should be easy to fix is the bombs though.    It came from the factory starting with the F model with those hardpoints and I've seen so many sources on that, it's not even funny.

 

edit- and don't you guys have this from IL-2?    The P-38 was in there and I don't remember it being as squirrely as this one is.   I've read the instructor could be causing a lot of issues though with that.

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Yeah, I think you are looking at the castrated lightning(model 322.)     Here is the G test data...  

 

http://www.wwiiaircraftperformance.org/p-38/P-38G-1_42-12687_FS-M-19-1538-A.pdf

 

 

Page 2, section 4.  Shows climb data at

10,000ft  2.81mins   3630ft/min

20,000ft  5.68mins   3280ft/min  (At 20,00 it's showing a carb.temp limiting factor)

30,000ft  9.46mins   2100ft/min  (At 30,00 it's showing a carb.temp limiting factor)

 

Page 1, section 1.   Flight Speeds

5,000ft True speed 346.5   at 1220 bhp

5,000ft True Speed 355.5 at 1320 bhp

14,700ft True Speed 378 at 1220 bhp (with a note stating 1320bhp can't be used to carburetor air temp limit)

22,600ft  True speed 404 at 1224 bhp (with a note stating Carb air temp limit and 44/7 inches hg)

24,400ft True airspeed 403 at 1175 bhp.

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found this too hope it helps.

http://www.wwiiaircraftperformance.org/p-38/p-38-wayne.html

 

 

The following curves compare the speed and climb performance of the P-38G, using the conservative Wright-Field data as a baseline (red), and that generated by Kelsey and Hough (orange) as the maximum limit (notice that the cleaner G model is faster than the J when at the same power). The power settings actually used in combat fell somewhere in between. Notice how the high CAT-induced power reductions above 15,000 feet affected P-38G performance. In fact, any high power setting with the carburetor air temperature above 45-50 degrees C was, supposedly, risky. Also shown are curves for a P-38J at WEP using both 130 and 150-grade fuels. 150-grade fuel was used by the US Eighth Air Force from mid 1944 to the end of the war. The P-38J curves are modified Wright Field data verified by power required calculations.

 

p-38-wayne-fig2e.jpg

 

it seems like we are not the only ones to think the P-38 could be doing better. colonel Ben Kelsey and Colonel Cass Hough of the Eighth Air Force Technical Section thought so too.

 

seems like Lockheed was being a bit too gentle to their baby and was underestimating how much the engines could actually take. the ["] btw are degrees in Celsius for the CAT (carburetor air temperature).

 

On the other hand, Ben Kelsey (now a Colonel) and Colonel Cass Hough, of the Eighth Air Force Technical Section, had different ideas about CAT. They were of the opinion (as were many of the fighter pilots) that American fighter engines were still being used at conservative, peacetime power settings, which were inadequate for combat. With this in mind they set out to determine just how much abuse a P-38 engine could take, and what they found surprised everyone.

The first P-38s to arrive in England were rated at 42" up to about 20,000 feet, 40" at 25,000 feet, with further reductions above that. Colonel Hough decided the best way to find out how much power was actually available without blowing up the engines was to remove the throttle stops and find out for himself. This made full throttle available at any altitude. Operating like this, Hough spent two weeks "abusing the engines", searching for their maximum limit. "We found that below 25,000 feet we could pull up to 60" of manifold pressure without material harm, and we could run as high as 40" at 40,000 feet (60" would yield around 1600 + bhp/ engine). He did warn that this kind of abuse should be of short duration. Col. Kelsey was busy doing the same thing at the Lockheed plant in California.

i especially find it amazing that they where able to keep 60" up to 25,000 ft without doing irreparable harm to the engine while Lockheed kept it locked down to only 42" up to 20,000ft.

adding the option for pilots to remove the throttle stop would be very beneficial to this plane (as a late tier upgrade) and would also add alot more risk of destroying the engine should the pilot use WEP for too long. 

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Someone called for roll rates on a P-38?

 

This is for a P-38J, which had Hydraulics, but yeah, BOOST probably refers to the hydraulics being active vs off, sort of like if you ever had your power steering go out on your car. Anyways, hope this helps...

 

p-38j-roll.jpg

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Someone called for roll rates on a P-38?

 

This is for a P-38J, which had Hydraulics, but yeah, BOOST probably refers to the hydraulics being active vs off, sort of like if you ever had your power steering go out on your car. Anyways, hope this helps...

 

p-38j-roll.jpg

whoa, am i reading this right? at 250mph it should be able to do 360 degrees in 2.6 seconds. the roll rate with the Hydraulic boost is really good.

 

i would assume that the P-38J without hydraulic assistance would be the same as the older G model as there weren't any major design changes other than adding dive flaps.

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From what I read on the 38's roll rate was that it actually had a good roll due to the large Ailerons.   The problem was the pilot had to muscle them and as speed increased the pilot struggled to move them, once he did that it would roll well.    You'll read it refered to as "Flick" roll rate and it suffered pretty bad the faster you went.   Once you got it rolling though,  it'd roll very very good.

 

When they added the boosted, hydrolic Ailerons it solved this issue and it freaking rolled very well at all speeds as the pilot didn't have to muscle it any longer.     I would think the early models would roll pretty similiar to the J without boosted.

 

Nice find!

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Thx for the roll rate.

 

Really interesting.

 

But as said, the main problem for the early models was the pilot strength, not the plane itself.Incredible to seehow fast it can roll =_=

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The growth of stick forces was what hampered the roll rate of fighters in general (and also elevator response, depending on design) well before compressibility has set in. Hydraulic controls to a large extent solve this, provided the control surfaces can withstand it and the wing doesn't twist (as was the case in many fighters with insufficiently stiff wings).

 

+1 for the data.

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whoa, am i reading this right? at 250mph it should be able to do 360 degrees in 2.6 seconds. the roll rate with the Hydraulic boost is really good.

 

i would assume that the P-38J without hydraulic assistance would be the same as the older G model as there weren't any major design changes other than adding dive flaps.

 

All the P-38s from the E version up had hydraulics, but the J was the first with hydraulically-boosted ailerons. So I'd say the Non-Boosted settings should be fairly close to the P-38G's performance. Even non-boosted, the roll rate isn't that bad.

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All the P-38s from the E version up had hydraulics, but the J was the first with hydraulically-boosted ailerons. So I'd say the Non-Boosted settings should be fairly close to the P-38G's performance. Even non-boosted, the roll rate isn't that bad.

ah i see, so the elevator on the G model would also be hydraulically boosted then?

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ah i see, so the elevator on the G model would also be hydraulically boosted then?

 

Nope. G was unboosted. J was when hydraulically boosted ailerons showed up. So yeah, the BOOST OFF graph should be appropriate for any P-38 before the J model. Roughly.

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Erm...

 

I like that roll-chart doubly since it gives you the 'no boost' option which is about where the G -should- be..

 

 

And this 'it's the G so it should suck" is utter rubbish..the G series is what gave the LIghtning it's german nickname in the first place.

 

That said currently the Flight model is WOEFULLY unstable at 225mph+ (using a joystick) to the point you literally can't go into any sort of actual bank without the plane flip spinning out on you, when this plane according to the test pilots is -very- stable  (due to the props spinning opposite ways cancelling each other out) at all speeds and alts...it just wasn't known to spin, in game right now...it's just unusebly bad from a stability point, and there's the climb rate and such that's lacking (Had a Ki-61A outclimb my P38G two days back)

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That is because the stall speed is off by 40% in the best case (currently). Which means it's critical AoA is wrong or that it's lift generation is wrong, and that will also make the plane stall out much sooner in a turn then it ought to.

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manifold pressure is currently wrong.

 

2013-08-23_00001.jpg[/URL]

 

instruments report manifold pressure at 32-35" (might get 35" if your using WEP) up to 20,000 ft while Lockheed had it set to 42" up to 20,000 ft when the first arrived in England. after field testing by the Eighth Air Force Technical Section sometime around February 1943 it was then set to 45" up to 25,000 ft. again using http://www.wwiiaircraftperformance.org/p-38/p-38-wayne.html as my source.

 

http://www.wwiiaircraftperformance.org/p-38/p-38g-tactical-charts.pdf

 

i assume these charts are after Kelsey's and Hough's report on the P-38s engines because the engines in these charts are also set to 44.5" (roughly 45" as after the reports the Eighth Air force set 45" as the limit) manifold pressure up to 20,000 ft.

 

EDIT: was reported and has been confirmed by a FM tester that it is being worked on and will be corrected.

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