How good (or bad) was the P-38, really?

[wuzak]

How good or bad was the P-38 really?

When it was good, it was very good, but when it was bad, it was better!

 

[ThomasP]

 

[FLYBOYJ]

How good or bad was the P-38 really?
Well it was in service before the USA entered the war and 10,000 were made so forget any comparison with late war or didnt even enter the conflict wonder weapons that did nothing at all.

It wasnt as good as a P-51 as a long range escort ,,,, so second to the best long range escort of the era in something vital to the whole USA and allied strategy.
It wasnt as good in MRCA roles as the Mosquito like PR, night fighter light bomber ,,,,, so second to the best in that category.

There are various states of "goodness" I cant see any case to be made for it being bad, without it, the allies are fighting a different war.

To add - it wasn't designed to fulfill either role

 

[RichardSuhkoi]

Think about how a constant speed propeller behaves when it's working properly. Ready for takeoff, brakes set, throttles coming up, prop (at full increase) is on its low pitch stops. As RPM approaches redline, governor increases pitch slightly to provide enough rotational drag to stop the RPM rise at redline.
Now, cleared for takeoff, brakes released, plane rolls forward, and with increasing forward relative wind, rotational drag decreases slightly and engine torque tries to spin the prop faster. How do you suppose the governor prevents this? You got it, it increases prop pitch to increase rotational drag back to the value that matches engine torque. As aircraft accelerates and forward relative wind increases, prop pitch has to keep increasing to keep RPM in check.
Now what happens if the prop stops responding to the governor as the aircraft accelerates through forty knots? Once again, you got it. Runaway! The faster the aircraft goes the faster the engine will spin. The only way to prevent engine disintegration is to reduce throttle, which quite likely will not support flight.
Another possible scenario, not related to electrical failure, is failure of a slipring or brush that transfers electrical power to the prop from the engine. If the "increase pitch" contact fails, the prop can only move in the "decrease pitch" direction, meaning that the constant "increase"-"decrease" commands that go on all the time become a ratcheting "decrease"-"decrease" series of responses, allowing engine torque to overwhelm propeller rotational drag and run wild.
Hope this has helped.

 

[RichardSuhkoi]

What little I know of the Curtiss Electric is that they had a backup electrical supply to improve reliability at least on some models. Also, massive redundancy on brushes with 6 fat brushes per slip ring. I'm sure the design intent was to fail fixed. But also the vibration is high and all those moving contacts you need to inspect this stuff regularly. Hydro props too- the servo seals can blow a leak and you pump out oil, that's why these often have a pitch lock fail safe device.

 

[IdahoRenegade]

I`d just like to clarify, there was nothing at all wrong with the original intercooler design. Its just that if you use the leading edge of the wing as your intercooler, you
leave yourself only an incredibly expensive and difficult route to increase its cooling capacity. Since this inevitably happened as everyones engines got progressively more powerful as time went, on, it was more a case than accidentally designed-in-obsolescence, than anything else. If you have the coolers in pods or just a traditional heat exchanger of some sort, its always a lot easier to make it deeper, or change the duct geometry or improve the exchanger fin density etc. It was just an extremely inflexible design, with no upgrade path - but it would have been fine at the engine outputs originally envisaged.

All very true. The wing leading edge design was selected because it did something no other intercooler approach did-it added no drag. Later model (J and L) aircraft got significantly more powerful engines, and could run them at higher power levels longer while maintaining CAT. But with the chin, core type intercoolers came additional drag, meaning the later aircraft were only slightly faster. I'm not sure about this but I would question if they were less fuel efficient as well. Granted, taking the intercoolers out of the wing leading edges freed up space for additional fuel tanks.

I always wondered if the '38 would have benefited from liquid to air intercoolers rather than air-air. It might have been possible to integrate liquid cooling passages with the leading edge skin and increase cooling, again without the increase in drag. Depends on the limitation was-was it getting heat out of the charge air and into the wing-skin or from the skin to atmosphere. Probably more susceptible to battle damage.

Some experiments were done with running later engines, 38H in particular, with the leading edge intercoolers, and allowing them to operate at higher CAT. I think Kelsey and Lavier (sp?) were involved with this, could be wrong. End result, they could run at much higher CAT than the AAC/F would allow them to, without observed problems.

 

[wuzak]

All very true. The wing leading edge design was selected because it did something no other intercooler approach did-it added no drag. Later model (J and L) aircraft got significantly more powerful engines, and could run them at higher power levels longer while maintaining CAT. But with the chin, core type intercoolers came additional drag, meaning the later aircraft were only slightly faster. I'm not sure about this but I would question if they were less fuel efficient as well. Granted, taking the intercoolers out of the wing leading edges freed up space for additional fuel tanks.

I always wondered if the '38 would have benefited from liquid to air intercoolers rather than air-air. It might have been possible to integrate liquid cooling passages with the leading edge skin and increase cooling, again without the increase in drag. Depends on the limitation was-was it getting heat out of the charge air and into the wing-skin or from the skin to atmosphere. Probably more susceptible to battle damage.

A liquid-air intercooler may have required a smaller chin for the radiator than the air-air intercooler did. The benefit would be simplified routing of the intake air.

Not sure that running liquid coolant in leading edge surface radiators would have given much benefit over the earlier intercooler system.

The downside, compared to the J/L, is not being able to run extra fuel in a leading edge fuel tank.

 

[Barrett]

Late to the Lightning Party but here's a perspective from the American Fighter Aces Assn.
When I was secretary in the 80s-90s I dealt with a variety of '38 guys from the ETO, MTO and PTO. It's a fair statement to say that nearly all of them adored it, especially in the J and L iterations. One of my closest friends cut his teeth on 38s (no victories) but though he made ace in a day in the Mustang, he usually referred to the 51 as "the funny plane" due to the CG issues.

Robin Olds was the only pilot to make ace in the 38 and 51 (he didn't know that until I mentioned it!) but loved the 38. However, he REALLY liked the 51 because it took him to where more swastikas grew.

F-86 double ace Ralph Parr broke into combat late in WW II (Pacific) and said he still had a romance with the 38.

Etc etc.

 

[drgondog]

Late to the Lightning Party but here's a perspective from the American Fighter Aces Assn.
When I was secretary in the 80s-90s I dealt with a variety of '38 guys from the ETO, MTO and PTO. It's a fair statement to say that nearly all of them adored it, especially in the J and L iterations. One of my closest friends cut his teeth on 38s (no victories) but though he made ace in a day in the Mustang, he usually referred to the 51 as "the funny plane" due to the CG issues.

Robin Olds was the only pilot to make ace in the 38 and 51 (he didn't know that until I mentioned it!) but loved the 38. However, he REALLY liked the 51 because it took him to where more swastikas grew.

F-86 double ace Ralph Parr broke into combat late in WW II (Pacific) and said he still had a romance with the 38.

Etc etc.

Barrett - Ahh I suspect Sid Woods - who flew 112 missions in 49th FG P-38G/H in 1943 with 2-1-0, 60 sorties in P-38J with 1-0 ground at 479th FG, with 8+missions 4th FG in P-51D with 5-0-0 air and 2-5 ground.

Olds and Zemke, when cornered, favored P-51 as best air supremacy fighter of choice. Ditto 'Big Jawn' Landers who had four in P-38J and Art Jeffries - who had one less P-38J (four) score but two more in the P-51D (ten) than Olds. Landers also told me that there were a lot of things to like about P-40E in SWP vs P-38F but he did not engage in P-38 before he came home on the way to ETO.

Ralph Parr was an all time character in the mold of Billy Hovde. Parr was described to me as the best shot in the USAF when he was flying F-86. I saw his gun camera film of the Russian IL-12 that he shot down N. of Hoha-Dung in mid 80s. The USAF and State Dept thought that he din't have a copy but he did. He hit left engine, right engine, then stitched the IL-12 from tail to nose and it blew up with Soviet Intelligence officers dotting the sky.

You may recall that the Sovs claimed he killed women and children and tried to bring him to World Court as a war criminal.

 

[Dimlee]

Ralph Parr was an all time character in the mold of Billy Hovde. Parr was described to me as the best shot in the USAF when he was flying F-86. I saw his gun camera film of the Russian IL-12 that he shot down N. of Hoha-Dung in mid 80s. The USAF and State Dept thought that he din't have a copy but he did. He hit left engine, right engine, then stitched the IL-12 from tail to nose and it blew up with Soviet Intelligence officers dotting the sky.

If you remember, what did he say, was it over China or North Korea?

Just for information, there are no intelligence officers on the official list of casualties.

Инцидент 7.27 – Последние жертвы последнего дня Корейской войны : Единая Корея – информационно-аналитический портал

 

[drgondog]

If you remember, what did he say, was it over China or North Korea?

Just for information, there are no intelligence officers on the official list of casualties.

Инцидент 7.27 – Последние жертвы последнего дня Корейской войны : Единая Корея – информационно-аналитический портал

Just north of Panmunjom Korea, The Sov IO's were en-route to advise N.Korea during 1953 peace talks.

Why would USSR ruin a good story by not disclosing IO's? That said, Parr was briefed re: Nature of IL-12 passenger constituency and the reason for specifically finding and shooting it down.

It was not an ordinary mission - with perhaps a similarity to Yamamoto mission in 1943. Parr led 16 F-86s of 4th FIW to intercept it just north of 38th Parallel. The Russians claimed he shot down a 'civilian airliner' over Manchuria and tried to have him charged as a war criminal,

 

[Dimlee]

Just north of Panmunjom Korea, The Sov IO's were en-route to advise N.Korea during 1953 peace talks.

Why would USSR ruin a good story by not disclosing IO's? That said, Parr was briefed re: Nature of IL-12 passenger constituency and the reason for specifically finding and shooting it down.

It was not an ordinary mission - with perhaps a similarity to Yamamoto mission in 1943. Parr led 16 F-86s of 4th FIW to intercept it just north of 38th Parallel. The Russians claimed he shot down a 'civilian airliner' over Manchuria and tried to have him charged as a war criminal,

Thanks. It was interesting to know what Parr said.
One of the strangest incidents of that war. Many details are still disputed. USA and USSR insisted on different locations, hundreds of kilometres apart.
Soviets (not Russians) claimed that it was a civilian aircraft, indeed. Yet the official list of casualties consists of officers and sergeants of three naval air regiments and military medics. Most probably it was Il-12 from the 593rd transport regiment of the Pacific Fleet, painted into civilian colours. The total number was 21 but the list included only 20 names. There were various "conspiracy theories" in the post-Soviet historic community.

 

[Deleted member 68059]

December 1942:

 

[drgondog]

Thanks. It was interesting to know what Parr said.
One of the strangest incidents of that war. Many details are still disputed. USA and USSR insisted on different locations, hundreds of kilometres apart.
Soviets (not Russians) claimed that it was a civilian aircraft, indeed. Yet the official list of casualties consists of officers and sergeants of three naval air regiments and military medics. Most probably it was Il-12 from the 593rd transport regiment of the Pacific Fleet, painted into civilian colours. The total number was 21 but the list included only 20 names. There were various "conspiracy theories" in the post-Soviet historic community.

A side note. Ralph Parr was one of many distinguished Colonels that I knew that retired as Colonels despite having great records of leadership. Zemke, Blakelee , Parr, Hill, Hovde, Gabreski come to mind. All of the ones I mentioned plus one other - Olds, who received his Star - but immediately assigned as den motherat USAFA, then a meaningless IG job -

All had one endearing quality (to me) aside from Leadership. All were brutally honest with degrees of some mitigating charm - when tey were telling someone fo 'f--k off'. Many future General officers learned to discard that phrase and were more suitably skilled in 'diplomacy'.

The reason I bring that up is that Ralph Parr was up at the top, with Blakeslee, at telling you exactly what he had on his mind if you asked a question. I believe his recant of the events, I did see the combat film (which proves nothing relative to actual identities and location). What came across strongly was he discussion of being briefed by USAF/ROK Army IO's regarding the nature of the target, the track and the ETAs. Also no question regarding is deep anger at the process the Soviets took to go after him personally at the World Court. That said, he was also amused at being the only fighter pilot so visible to Soviet Union until Gary Powers.

 

[drgondog]

December 1942:

View attachment 717478
View attachment 717479

View attachment 717480

Great find.

 

[GregP]

I met Ralph in the 1980s -90s at Scottsdale (Arizona) airport when I got my license there and was flying out of a club based there. As you sate, he was a character. His stories did not glorify Ralph, they made you feel the danger of aerial combat and how it doesn't care who you are.

 

[AZRailwhale]

Rightly or wrongly the USAAC viewed the P-38 as their premier fighter in 1942 and early 1943.
A lot of confusion surrounds in use in the ETO as at least two groups were declared operational and 3rd was working up in England in the fall of 1942.
However both operational groups were sent to North Africa for Operation Torch and the 3rd group gave up their planes and some of their pilots as replacements.
This is from memory and may be off a bit.
The P-38s completed just over 300 sorties in Europe in the fall 1942 and would not show up in Europe again (operationally) until the fall of 1943.
There may have been some recon versions.

P-38s fought all over the Pacific and in NA and Italy in late 1942 and through the first 3/4s of 1943 before they returned to to England.

Some of their troubles have to be seen in that light. Darn little experience in B-17 bomber escort in European winters until many months after the P-51B entered production.

When the P-38s were fighting over Northern Europe, they were green units fighting the cream of the Luftwaffe over its own airfields in its own radar coverage. The Luftwaffe could pick and choose where and when to fight, and the Lightnings still almost got a one-to-one kill ratio. When looked at in that light the P-38s performance doesn't look so bad. If Doolittle had held on until the late Js and Ls were deployed the Lightning's record would look a wgh9le lot better.

 

[AZRailwhale]

I thought Snowygrouch was going to beat me to it. HIs book makes clear (I've read it cover to cover) that the original P-38 models had a really poor intercooler design that was finally improved on the P-38J. In addition, it really needed the equivalent of the Fw 190's Kommandogerät as there were too many controls to be adjusted to properly control the engines, props and turbochargers.

The P-38 was originally designed as a limited production fast climbing interceptor. That's why it had such a Rube Goldberg cooling system.

 

[Shortround6]

The P-38 systems (both intercooler and radiator) were designed for a 1000hp engine. Not a big surprise when they didn't perform well when trying to deal with 1325-1600hp engines.

The radiators actually did fairly well. The FIX involved making the scoops larger and mounting the existing radiators further out from the nacelle center line into the bigger scoops giving more direct access to the cooling air. The change from all Glycol to a water/Glycol mix for coolant also helped. Not done at the same time ?

As far as the intercooler went, consider the intercooler on the B-24.

This was the size intercooler you needed for a 1200hp engine at 25,000ft in 1940-42. The entire right side air-scoop was devoted to the intercooler, the air for carb went in the left side with the oil cooler air. Intercooler design got better
The P-38 also changed quite a bit.

 

[AZRailwhale]

The P-38 systems (both intercooler and radiator) were designed for a 1000hp engine. Not a big surprise when they didn't perform well when trying to deal with 1325-1600hp engines.

The radiators actually did fairly well. The FIX involved making the scoops larger and mounting the existing radiators further out from the nacelle center line into the bigger scoops giving more direct access to the cooling air. The change from all Glycol to a water/Glycol mix for coolant also helped. Not done at the same time ?

As far as the intercooler went, consider the intercooler on the B-24.
View attachment 718711
This was the size intercooler you needed for a 1200hp engine at 25,000ft in 1940-42. The entire right side air-scoop was devoted to the intercooler, the air for carb went in the left side with the oil cooler air. Intercooler design got better
The P-38 also changed quite a bit.
View attachment 718712

I believe you are wrong. The early P-38s had the intercooler lines running through the leading edge of the wings for cooling. In operational units they tended to leak causing runaway turbochargers.