P38 a super plane?

[Angus]

From Crumpp:
"I certainly have a problem when pilot stories become the basis for aircraft performance. "

Well, Crumpp, I remember someone on these boards who tried with calculations and a graph, to prove that the 109 was a better turner than the Spitfire.
I decided to rather belive the 95% of the pilot stories who claim otherwise.

The point of the story; 100 stories vs a couple of documents, well.......uhh, hmmmm??.??

In my mind the P38 (after reading this thread) stays as a fine fighter with some unique qualities and no Achilles heel....

[Crumpp]

Well, Crumpp, I remember someone on these boards who tried with calculations and a graph, to prove that the 109 was a better turner than the Spitfire.

Exactly.  I have a nice EM diagram from an actual flight test that definitely shows the Spitfire as the better turner.

They were close and under portions of the envelope equal so it is easy to see how pilots "outturned" one another from the diagram.

I have yet to see a single pilot stories that when pressed for details could not be explained scientifically.

Including Luftwaffe veterans "outturning" Yaks in an FW-190A8.

In my mind the P38 (after reading this thread) stays as a fine fighter with some unique qualities and no Achilles heel....

It was a very innovative fighter and the only twin engine fighter to successfully compete with single engine fighters on performance alone.  

It certainly had some well-documented flaws.  If these were Axis documents attempting to show P38 performance then I would be suspect.  You cannot expect someone not trained on a type to effectively service and fly it to it's full potential.  These are however:

1.  Flight test examining all parameters of flight, Speed, climb, range, drag, power loading, etc...

2.  This information lines up perfectly with both a tactical trial of the Zeke when the P38 is compared to it's USAAF contemporaries AND a flight test conducted to determine the best way for the P 38 to destroy the FW-190.

3.  A collection of informed opinions from a wide knowledge base of US Fighters to determine which is the BEST performing fighter under a variety of missions (escort, attack, free, etc...).  To say the P 38 was not rated high is a vast understatement.  In fact experienced pilots rated it miserably short of the required performance.

It's size and maneuverability preclude it from being a premier fighter in the US inventory.

It's huge level speed advantage over the Japanese fighters did allow it success in the Pacific.

Crumpp

[F4UDOA]

WW,

Like I said it is not a very good comparison but you made some points that are not correct based on solid documentation.

You said

Enormous range? Compared to what? Even the P-47D-25 out-ranged the F4U-1 series.

Do you have a copy of the F4U-1 POH? Because of the lower drag of the F4U-1 even with almost half the fuel of the P-38L with two 300 gallon DT's the F4U-1 had almost exactly the same range. And this is not the maximum F4U-1 capicity for takeoff.

From the P-38L POH
Two 300Gallon DT's 1,010gallons of total fuel on board.
maximum range one way using 950 gallons (the rest for takeoff and climb)
2200miles
 
From the F4U-1D POH
Two 170 gallon DT's 577 total gallons of fuel.
Total range on 560 gallons
2,080 miles.

The F4U could travel the same distance on half the external gas.

You said

As to acceleration, the P-38 would leave a -1 series Corsair behind like it was tied to a tree. I doubt that the F4U-4 could accelerate faster than the P-38L, much less its far less energetic and older sibling. Look at Dean's calculations (you seem to like referring to him), he puts the P-38L well ahead of the F4U-4 and likewise, the P-38F well ahead of the F4U-1. If he's right (and he probably isn't far off), its no contest.

Based on what? The P-38 acceleration claims are as bad as the lockness monster claims. It just didn't exist. The TAIC report shows the P-38L at full combat power was beaten by a P-47D30(that could not out accelerate a F4U-1) and a P-51D.

Lets check the facts
P-38L power loading
3200HP
17,500LBS
Power loading= 5.468

F4U-1D Power loading
12,175lbs
2250HP
Power loading= 5.411 <=Winner, later F4U-1D was rated a 2300HP by wars end

P-38L Cdo= .0278
F4U-1D= .020<=winner

Well how about instant acceleration like take off from a short distance? The P-38 should be able to take off and fly circles around the F4U like the Mustang right?

Takeoff from hard surface runway mil power 0 wind From the POH's
P-38L 17,400lbs- 1030FT
F4U-1D 11,700lbs- 680ft <==========Winner

F4U-1D with a 2,000lbs bomb 14,200LBS= 1,110FT <=only 80 ft more than the P-38L empty?

This clearly does not look like the F4U-1 is tied to a tree?

I know you will claim 1725HP from the P-38L however any WW2 aircraft could be overboosted. I also know for a fact the R2800 was overboosted regularly and could run at high boost levels at least as well as an Allison could.  So we should both stick to the manufactures recomendations for output HP espicially since there is nothing to show the P-38 doing any better than listed performance except homemade charts and graphs.

You may also quote Francis Dean's AHT.

Well he list the loaded weight of the P-38L at 16,880LBS the Weight of the F4U-1D through the book at 12,289LBS and the Cdo at .0267. Where these numbers come from I don't know but I do know they are all wrong based on Vought and NAVAIR docs detailing weight and drag.

You may say that the P-38 outclimbed the F4U-1 by a wide margin so why would it not accelerate it?

Well first climb only takes place in a very small area of the power curve were Cdi is most important at speeds around 150MPH. However acceleration crosses the entire speed range and is most important at combat speeds above 200MPH.

Also and even more importantly from the document I retreived from Vought shows the P-38J climbing to 20,000FT in 5.9 minutes. If this was the performance of the P-38J then how can the P-38L have the same climb rating with 1,100lbs more lbs and the same HP. I know that subtracting 1,000lbs from the F4U-1 reduces climb to 20K by 1 minute. So would the addition of 1,000lbs to the P-38L increase the time to climb by 1 minute. Test against the P-51D and P-47D would seem to show just that.

You said

I can't find a single reference that states that anyone was flying the F4U-1 in Korea. The first F4U units to see combat in Korea were VMF-214 and VMF-323. They were flying the F4U-4B/C.

I am researching my sources, standbye.

Then you said

As to comparing the F4U-1D to the P-38L (similar vintage), where does the Corsair do better than the Lightning? Climb? No, not even close. Standard bomb load? Nope, the P-38Ls were certified for 4,000 pounds on their hardpoints. Range? Forget it... A P-38L with 310 gallons under each wing could stretch its legs to over 3,000 miles. Milo Burcham flew a P-38F that far, and it carried 110 gallons less than the L model. Speed? Slight edge to the Corsair down low... P-38L wins from 20k on up. Roll rate? F4U below 300 mph, P-38L above 300 mph. Handling? P-38L wins hands down at low speeds, give the F4U the edge above 400 mph. Generally speaking, the F4U is outclassed in a dogfight vs the P-38L.

 I have to dig my source for the F4U-1D in Korea but never the less it was in active service long after the P-38 was on the airshow circuit.

2. Loadout, the F4U-1 took off in combat with up to a 17,000lbs load. That is 5K or external stores. I have never seen anything to show the P-38 carrying more than 4K.

3. Speed- The F4U-1D was faster up to 25K, slower to 30K and then even from 30K up. This can be proven by many different sources

4. Dive - The F4U-1 was rated much faster allowable speeds in a dive even with P-38L dive break the posted restriction on the P-38L was 420MPH IAS, 460TAS where as the F4U was limited to 410Knots IAS/480MPH IAS or 576MPH TAS at 10,000FT.

So the P-38L was limited to 116MPH slower diving than the F4U-1. Also it was also only rated for 6G's from the POH. as to 7G's for the F4U-1 at 100% weight.

5. Turn ability- The F4U-1 Vn diagram from the POH indicates a 3G stall at approximately 165MPH CAS at 12,000lbs. The P-38L shows a 3G stall at approx 165MPH CAS with no weight listed. For reference the P-51D manual Vn diagram is shown at empty weight. This may mean the same for the P-38 in which case the best the P-38 could hope for would be a tie.

6. Roll- The F4U outrolls the P-38L up until 400MPH where a restriction on the F4U ailerons lowers the allowable rollrate. This was common Navy practice and the same restriction is listed on the F8F and F6F at even slower speeds. Also the P-38 had horrible roll inertia cause by it's twin boom engines. An object in motion tends to stay in motion.

7. Low speed handling- The F4U outhandled any of it's Army couterparts at low speed hence the lateral control rating at the JFC of second best ailerons at 100MPH. It also had the best elavator, best harmonzation of controls and best stability in a dive. You can't compare a land based A/C to a carrier based one in low speed handling.

8. Climb- P-38L no question.

Other than climbing away I cannot see an advantage for the P-38L.

You  also mentioned Lindberg prefering the P-38 to the F4U. I would love to read that if you have it or know the source. I have a quote from Rex Barber P-38 pilot of Yamamoto fame where he claims if the US could build only one fighter/Bomber in WW2 it should have been the F4U. And he was a AAF pilot.

Anyway it's late and I'm exhausted.

Nighters

[BUG_EAF322]

But the AH P38 keeps beating down the corsair.

Somehow u couldn't convince them .

So how good is ur proof.

Seen them been angry about ur statements.

[Widewing]

Originally posted by F4UDOA
WW,

Like I said it is not a very good comparison but you made some points that are not correct based on solid documentation.


(Some snipping of post was required to meet length limits)

The documentation may be solid, but the selective application of data is not... I'll demonstrate below a tendency to apply only favorable data without defining altitude or application or mention that data may exclude some important facts.


Do you have a copy of the F4U-1 POH? Because of the lower drag of the F4U-1 even with almost half the fuel of the P-38L with two 300 gallon DT's the F4U-1 had almost exactly the same range. And this is not the maximum F4U-1 capicity for takeoff.

From the P-38L POH
Two 300Gallon DT's 1,010gallons of total fuel on board.
maximum range one way using 950 gallons (the rest for takeoff and climb)
2200miles


The Manual also deducts for warm-up, climb, 15 minutes at MIL power, 5 minutes at WEP, and a 45-60 minute reserve and cruising at 12,000 feet. Maximum practical range (ferry range) for the P-38L was 2,550 miles. Actual maximums could exceed 3,000 miles when employing the fuel conservation methods used by Milo Burcham and Lindbergh. However, this was not for anything but demonstration, but was demonstrated many times. Obtaining maximum range entailed leaning the mixture manually, rather than simply pushing the mixture into the autolean detent which is what the manual indicates. This is why you find the 49th and 475th FGs flying combat missions of 1,900 to 2,000 miles round trip with just two 165 gallon drop tanks. Prior to Lindbergh, these Groups were flying missions of no more than 1,400 miles round trip and landing on fumes. By the way, Lindbergh did teach F4U and P-47 units the same thing.

 
From the F4U-1D POH
Two 170 gallon DT's 577 total gallons of fuel.
Total range on 560 gallons
2,080 miles.


Is this not ferry range, discounting warm-up, climb-out, MIL power, Combat power and no reserve whatsoever, as well as flying at just 5,000 feet? This is a theoretical maximum, not what a pilot could expect. Read Dean's notes on the F4U-1 range on page 512 of AHT.


The F4U could travel the same distance on half the external gas.


Two interesting statements...
1) No, the F4U-1D cound not come close to the same radius of action as the P-38L
2) The second half of that statement is kinda silly. The P-38 had two engines.


Based on what? The P-38 acceleration claims are as bad as the lockness monster claims. It just didn't exist. The TAIC report shows the P-38L at full combat power was beaten by a P-47D30(that could not out accelerate a F4U-1) and a P-51D.


If you have a copy of the TAIC test, please post it. I have serious doubts as to power settings or state of tune.


Lets check the facts
P-38L power loading...

P-38L Cdo= .0278
F4U-1D= .020<=winner


Dean shows drag coefficients of .0270 for the P-38 and .0267 for the F4U-1D. You state .020 for the Corsair, which is considerably less than the P-63. Better check that again. Dean shows that the P-38 and F4U-1D have very similar drag... Nice try though.

As to power loading, you are making a strawman argument by being data selective using sea level numbers only. Who is the winner at 10k, 20k, and 30k? The P-38L is, by an ever widening margin as you climb. As it is, the lowly FM-2 has a better power loading that the F4U-1D at sea level. Would it be fair to imply that the FM-2 generally has a lower power loading than the F4U-1D based upon sea level data? No, because the F4U has the advantage as altitude goes up. Sorry, this one doesn't wash either.


Well how about instant acceleration like take off from a short distance? The P-38 should be able to take off and fly circles around the F4U like the Mustang right?

Takeoff from hard surface runway mil power 0 wind From the POH's
P-38L 17,400lbs- 1030FT
F4U-1D 11,700lbs- 680ft <==========Winner

F4U-1D with a 2,000lbs bomb 14,200LBS= 1,110FT <=only 80 ft more than the P-38L empty?


Please, we should compare things that relate to combat capability. Using your implication, the FM-2 should accelerate better than the F4U-4, because it can get airborne in 1/4 the distance.



I know you will claim 1725HP from the P-38L however any WW2 aircraft could be overboosted. I also know for a fact the R2800 was overboosted regularly and could run at high boost levels at least as well as an Allison could.  So we should both stick to the manufactures recomendations for output HP espicially since there is nothing to show the P-38 doing any better than listed performance except homemade charts and graphs.


Are you insinuating that the chart is bogus? Allison rated the V1710-111/113 at 1,725 hp. It was the USAAF that derated the engine to reduce wear. In the field (please locate and ask any P-38L Crew Chief), the engines were rigged for full rating courtesy of Allison field reps. This is borne out by both Lookheed and Bodie, who discusses this in his book.

(snipped)


 I have to dig my source for the F4U-1D in Korea but never the less it was in active service long after the P-38 was on the airshow circuit.

Both P-38s and F4Us raced for the Thompson Trophy. P-38s were competitive, F4Us never were. However, the F2G did win twice, before the F8Fs and P-51s took over for good.

No F4U-1s were aboard carriers in 1950.


2. Loadout, the F4U-1 took off in combat with up to a 17,000lbs load. That is 5K or external stores. I have never seen anything to show the P-38 carrying more than 4K.


Like the F4U, the P-38L could carry 2,000 pounds on each under-wing pylon, and rockets on the zero-length rails. Max load is virtually the same.


3. Speed- The F4U-1D was faster up to 25K, slower to 30K and then even from 30K up. This can be proven by many different sources

Overlaying speed charts shows P-38 advantages at several altitudes, not just above 30k.

5. Turn ability- The F4U-1 Vn diagram from the POH indicates a 3G stall at approximately 165MPH CAS at 12,000lbs. The P-38L shows a 3G stall at approx 165MPH CAS with no weight listed. For reference the P-51D manual Vn diagram is shown at empty weight. This may mean the same for the P-38 in which case the best the P-38 could hope for would be a tie.

Dean calculates a slight edge for the P-38. Of course, this discounts the P-38's fowler flaps, which alter things greatly in favor of the Lightning. In AH2, I'd be happy to demonstrate the P-38's turning ability against you in the F4U-1D. But be advised, it'll be a short and ugly demo.

6. Roll- The F4U outrolls the P-38L up until 400MPH where a restriction on the F4U ailerons lowers the allowable rollrate. This was common Navy practice and the same restriction is listed on the F8F and F6F at even slower speeds. Also the P-38 had horrible roll inertia cause by it's twin boom engines. An object in motion tends to stay in motion.

I have seen only one reference to F4U roll rate and that one stops at 280 mph. At that speed it was rolling at 90 degrees/sec. At 280 mph, the P-38L rolls at 80 degrees/sec, and that's not much of a difference. At 350 mph the P-38 is at 92 degrees/sec and continues increasing up to 98 degrees at 450 mph. If you have some other F4U data, please post it.


7. Low speed handling- The F4U outhandled any of it's Army couterparts at low speed hence the lateral control rating at the JFC of second best ailerons at 100MPH. It also had the best elavator, best harmonzation of controls and best stability in a dive. You can't compare a land based A/C to a carrier based one in low speed handling.

Low speed handling??? LOLOL Yeah, the Ensign Eliminator was the king of stability at low speeds! Aileron effectiveness is nice, but won't keep the Corsair from rolling on its back if you apply full power at 100 mph. Look again at the JFC and read what it says about handling 5 mph above stall. Your F4U-1D is at the bottom of the list. The torqueless P-38 was the best handling fighter at low speeds by a significant margin. That's indisputable.

8. Climb- P-38L no question.

Other than climbing away I cannot see an advantage for the P-38L.

You  also mentioned Lindberg prefering the P-38 to the F4U. I would love to read that if you have it or know the source. I have a quote from Rex Barber P-38 pilot of Yamamoto fame where he claims if the US could build only one fighter/Bomber in WW2 it should have been the F4U. And he was a AAF pilot.

I read the Lindbergh comment somewhere, but I can't recall exactly, except that it was in a biography. I believe he told this to McGuire.

You might be surprised that I tend to agree with Barber. If only one fighter could have been made, the F4U was likely the best choice. Not because it could replace the P-51, P-47, P-38, and F6F, because each of those was a stellar aircraft within its designed use. The F4U was at least adequate for every role, except high altitude escort where a different supercharger would have been needed. Adding to its utility was it being a carrier fighter. I have stated many times that the F4U-4 was the best fighter-bomber of WWII, bar none. Had the demand been there sooner, the F4U-4 could have been in service up a year prior to its actual service introduction. Neither Vought or the Navy seemed to get in a hurry until the Japanese kamikazi problem arose.

In terms of facing the Luftwaffe, the F4U-1 would have difficulty with the higher flying Bf 109s. I believe the F4U was a match for the Fw 190A series fighters, but they could never meet the 109s on even terms at 30k like the P-47s and P-51s could. Again, it wasn't designed to either.

My regards,

Widewing

[MANDO]

Originally posted by BUG_EAF322
But the AH P38 keeps beating down the corsair.

Waiting for you to ask Pyro to fix the P38: max of 15 mins military power.

[Crumpp]

The documentation may be solid, but the selective application of data is not... I'll demonstrate below a tendency to apply only favorable data without defining altitude or application or mention that data may exclude import facts.

Where is the selective data?  The documents are posted for all to see and if you were not so blinded by your fandom could see they do show the P 38 has having good points.  It did very well against the FW-190A3 and IMO the planes match up evenly.  You wish to have a double or triple superiority which did not exist.

Are you insinuating that the chart is bogus?

Come on.  It's a power point slide.

Not quite proof of anything other than someones skill with powerpoint.  It is pretty, though.

 

you are making a strawman argument

Is that your word of the week?  Post it enough and it becomes the truth?? WTF!

f you have a copy of the TAIC test, please post it. I have serious doubts as to power settings or state of tune.

It's already been posted.  

Guess it must be another P 38 conspiracy going on.

The P-38L shows a 3G stall at approx 165MPH CAS with no weight listed.

Then the document is worthless and any conclusions drawn off it are crap.

What was that strawman thing you were harpin on earlier??

Please, we should compare things that relate to combat capability.

They did at the JFC and the P 38 did not make the mark.  It was a great fighter bomber they said.


Crumpp

[Scherf]

Widewing:

Thank you for your information about the drop tanks, as it puts a number of points into perspective, especially the loadout used, and in which theatre.

Cheers,

Scherf

[Widewing]

Originally posted by Crumpp
Where is the selective data?  The documents are posted for all to see and if you were not so blinded by your fandom could see they do show the P 38 has having good points.  It did very well against the FW-190A3 and IMO the planes match up evenly.  You wish to have a double or triple superiority which did not exist.

Crumpp

Crumpp, just so that you don't continue to be confused, when I'm responding to YOUR posts, I'll add into the subject line, "Hey Numbnuts!" (see above)

My regards,

Widewing

[Crumpp]

Crumpp, just so that you don't continue to be confused, when I'm responding to YOUR posts, I'll add into the subject line, "Hey Numbnuts!" (see above)

Don’t cloud the issue.  You accused anyone who is not in the P 38 click as posting "selective" data.  Just as you accused every engineer, manufacturer, Military Officer or Organization who has said anything against the P 38 as being a member of some "conspiracy" to keep the P 38 down.

So answer the question put to you fairly.  You made the accusation Now Back it up or retract it!!

 Where is the selective data? The documents are posted for all to see and if you were not so blinded by your fandom could see they do show the P 38 has having good points. It did very well against the FW-190A3 and IMO the planes match up evenly. You wish to have a double or triple superiority that did not exist.

I have the right to respond to your blatant accusation that information in this thread was somehow slanted against the P 38.  That is a huge untruth.  You should thank F4UDOA for adding to your, what must be meager, document collection.

Looks better than a few PowerPoint slides too!!  

If things are as you say Widewing then it should be very easy to find a wealth of documentation from flight test's to back it up.  So……

We are waiting….

Crumpp

[Angus]

F4UDOA:
I saw your comparison of power loadings.
Well, there are other things to bear in mind in that category, some of who may be in the P38's favour.
Now, just pointing out some variants, this thread is already flamy beyond a Spit-109 threadfest, and I didn't think that had been possible.
Ok, here goes. Some factors for the fighter:
1. The P38 has no torque trimming drag. Contra-rot you see.
2. The Span loading. Check it out. (I didn't but...)
3. Wing loading.

All affect the flight. Always bear in mind that it depends on wingloading + power how well an aircraft accelerates until the parasite drag factor overcomes the induced drag. So, that from-the-runway thingie boggles me, and I guess that is why so many acceleration tests were done by opening up at cruising speeds, already airborne.

Anyway, just some coins into the debate, hope I didn't step on somebodys tail.

Regards

Angus

[Widewing]

Snipped Crumpp's lies in the interest of his own mental health...

Let me pose a question: Were you elected Village Idiot by popular vote, or did you rise to that position through experience, hard work and dedication?

Clearly, you will fabricate anything, say anything and lie about anything rather than face the fact that your entire contribution in this thread has been devoid of substance. You're a black hole, you suck the life out of any thread you infect. Now do us a favor and revert to your speedbump existence and let those of us who can disagree without fabricating attributions enjoy the give and take of honest discussion.

Widewing

[Crumpp]

Snipped Crumpp's lies in the interest of his own mental health...
Clearly, you will fabricate anything, say anything and lie about anything rather than face the fact that your entire contribution in this thread has been devoid of substance. You're a black hole, you suck the life out of any thread you infect. Now do us a favor and revert to your speedbump existence and let those of us who can disagree without fabricating attributions enjoy the give and take of honest discussion.

Lying is a huge accusation.  One I don't take lightly at all.  Prove it or I will call you on it.

Clearly when the facts do not go your way you resort to the above behavior.  Pathetic.

All you have to do is produce some actual documentation to back up your claims.  Since you cannot you blow a gasket.

Crumpp

[Crumpp]

1. The P38 has no torque trimming drag. Contra-rot you see.

No but it does have both the lift bonus from the prop vortex's AND the drag penalties they incur.  The P38 also has twice the cooling drag.

Remember the power of induced drag is like a wall.
 
http://www.av8n.com/how/htm/4forces.html#fig-power-ias


Once the "wall" is breached, it is an inconsequential force.  It's is not as "steady" an application of force as the form drag of the P38.  We are talking a large surface area.

Wing loading.

Wingloading is horrible on the P 38.  It is a heavy airplane.  Now the flaps do give it some advantage in overcoming this but even Lockheed recognizes that they are a trade off.  Flaps down = high drag = big energy bleed.

The P38 has by far the best flap design you can have to make this trade off.

The Span loading. Check it out. (I didn't but...)

I would have to see a chart but being that it falls in the design timeline after the spitfire but before the FW-190 I would be surprised to see major innovations over other US fighter designs.  The designer's were fully aware of the benefits of elliptical distribution and how to manipulate the airfoil to achieve it.

So, that from-the-runway thingie boggles me, and I guess that is why so many acceleration tests were done by opening up at cruising speeds, already airborne.

I think it is pretty applicable acutally.  It shows the time from the stalled realm to speed.  Aircraft can have different accelleration in different parts of the power curve.  Using the FW-190 as an example since I am most familiar with it, it has excellent accelleration to around 250 IAS.  After that it is unremarkable.  I have a measurement of it somewhere at different altitudes...

I don't see anything that aerodynamically calls to question the findings of the JFC.

Crumpp

[BUG_EAF322]

Slot conclusion:

The P38 beated the crap out of a FW190 in a close dogfight.

Just like in AH i'm sorry that is the way it is.

I bet u can't change it,so now stop the war on the P38 since u really like to talk/tune it down.

If u fair go post a thread and say HTC screwed the P38.

Show me some guts.