WI: NACA Modified P-38

Will the various fixes proposed earlier in TTL make a difference in the aircraft given to the RAF?

Not so much, apart from several mph gained.
RAF got only the non-turbo Lighthning I (few examples), they cancelled the order for those and the turboed Lightning II. Both versions were to be paid by UK (cash & carry), the order was signed and then ammended before the Lend-Lease started. The Lightning I was barely as fast as Spitfire I or II, but much more expensive.
 
Not so much, apart from several mph gained.
RAF got only the non-turbo Lighthning I (few examples), they cancelled the order for those and the turboed Lightning II. Both versions were to be paid by UK (cash & carry), the order was signed and then ammended before the Lend-Lease started. The Lightning I was barely as fast as Spitfire I or II, but much more expensive.

Lockheed was over a barrel. They didn't want to sell the turbo-supercharger less "castrated Lightnings" to the British but they wanted/needed the money. The British also wanted same-handed engines which removed the advantage of no torque as well as causing longer take off runs as the LIghtning's centre wing worked better with both prop washes spiralling oppositely upward and outward as was established with the first test flights. Lockheed did object to the British Air ministry's mistaken requirements but folly got its way as it so often does.

Perhaps in this ATL with an earlier better performing P-38 that could mean more solid support and more money from the U.S. Army Air Corp. So Lockheed management insists that the British Air Ministry accept the P-38 as is or no sale. There by forcing them to buy what they need instead of what they mistakenly want. Similar to what occurred in OTL with the 4 engined Lancaster and the Mosquito where as excellent planes were produced over the Air Ministry's initial objections.

But the dates and the timing between OTL and this ATL don't line up properly for this to occur sadly.
 
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Lockheed was over a barrel. They didn't want to sell the turbo-supercharger less "castrated Lightnings" to the British but they wanted/needed the money. The British also wanted same-handed engines which removed the advantage of no torque as well as causing longer take off runs as the LIghtning's centre wing worked better with both prop washes spiralling oppositely upward and outward as was established with the first test flights. Lockheed did object to the British Air ministry's mistaken requirements but folly got its way as it so often does.

Perhaps in this ATL with an earlier better performing P-38 that could mean more solid support and more money from the U.S. Army Air Corp. So Lockheed management insists that the British Air Ministry accept the P-38 as is or no sale. There by forcing them to buy what they need instead of what they mistakenly want. Similar to what occurred in OTL with the 4 engined Lancaster and the Mosquito where as excellent planes were produced over the Air Ministry's initial objections.

But the dates and the timing between OTL and this ATL don't line up properly for this to occur sadly.

One of the interesting WI I saw once was the idea that a few Lightnings making it to the BOB, a plane that was built around the mission of interceptor in that exact role.
 
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This is really cool. The P-38 is one of my all-time favorite aircraft and it's good to see someone give it some love.

I do, however, have one quibble: I'm pretty sure your speed conversions in the flight test scene are incorrect. 325 knots = 374 mph, not 480.
 
Normally, in a multi-engine when one dies you simply firewall the throttle on the other and use the ailerons to keep it level... Proper training (and reading the damn flight manual) would solve that.
It appears I misread something somewhere, then...or memory is faulty. (I do know LeVier was sent over to demonstrate the right way, FWIW....)

You also make good points on maintenance, logistics, & cost. (IMO, the first two are more significant in the scheme of things.) More work & more spares means more headaches. And wouldn't the P-38 inevitably use more fuel than the P-51? Another problem... All spares & fuel have to come across the Pond, which means U-boat bait...

I wondered about spares commonality with Spitfires & Hurricanes being a benefit to the P-51; there wouldn't be many (any?) P-40s still around. (P-39s, either.) That, however, may require a "pooling" of spares that's not historically accurate or reasonable...

Thinking of the PTO, the greater range offers opportunities to attack Japanese targets that would've been out of range OTL plus, probably, better defensive patrols (able to pursue attacking Japanese farther, able to intercept further out possibly). There are butterflies at play there, but maybe only small ones... Might be something like the Yamamoto intercept is mooted, if not executed, sooner, because it becomes practical sooner; my guess is, that requires such a particular confluence of events, TTL it won't even happen.
Get Vultee building P-38s two years earlier. Expand the production facilities at Lockheed Burbank. Could require a second source for the Allisons.
Excellent suggestions. (Not sure second source for V1710s would be needed, but not a bad idea.)

A thought: are there enough new-builds to fit radar for a NF version, & butterfly away the P-61? (Looking at the cockpit pod, it looks bigger enough to add a true second seat.)
7 October 1941
Burbank, California, USA
Bravo on a well-told piece. The detail was enough I felt like I was right in the cockpit. Very well done. (I take it the quotes from the NACA were real ones?)
 
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It appears I misread something somewhere, then...or memory is faulty. (I do know LeVier was sent over to demonstrate the right way, FWIW....)



A thought: are there enough new-builds to fit radar for a NF version, & butterfly away the P-61? (Looking at the cockpit pod, it looks bigger enough to add a true second seat.)

The P-38L second seat looks cramped as hell. Radar operators would appreciate the extra room.
 
There is a lot to respond to that I missed over the last couple days and I will get to it all. I am working on the next update right now, which is taking most of my focus.
I do, however, have one quibble: I'm pretty sure your speed conversions in the flight test scene are incorrect. 325 knots = 374 mph, not 480.
The conversion was not from knots to MPH, but from Indicated Air Speed in MPH to Actual Air Speed in MPH. Indicated Air Speed, especially at altitude, can be quite a bit less that actual Air Speed because the pitot relies on pressure for its measurement. At altitude there is less ambient air pressure and this effects the pressure in the tube so the IAS needs to be adjusted to get an AAS. In addition to this, the max speeds Virden would have estimated from his dive would not take into effect Compressibility errors so his final estimate of 550mph is probably a little faster than he was actually diving.
 
The P-38L second seat looks cramped as hell. Radar operators would appreciate the extra room.

Lockheed_P-38E_-Swordfish-_Laminar_Flow_Wing_Testbed_061018-F-1234P-009.jpg


The Lockheed Swordfish, or Nosey, was used for research, but could have made a right fine nightfighter basis. It was described as having better diving characteristics.
 
One of the interesting WI I saw once was the idea that a few Lightnings making it to the BOB, a plane that was built around the mission of interceptor in that exact role.
I think a fully capable Lightning (say a J-25 or even L) in 1940 for the BoB would be the ultimate Lightning-wank. With its Rate of Climb and performance it would a helluva shock to the Luftwaffe and likely a huge demoralizer to the German Air crews. Unfortunately, I just can't see a way to get a combat ready P-38, even an early F or G model, to the UK in time to take part without ASBs getting involved.

It appears I misread something somewhere, then...or memory is faulty. (I do know LeVier was sent over to demonstrate the right way, FWIW....)
No, you are absolutely right. The first groups to get the P-38 had problems adapting to the single-engine behavior of the P-38 and it caused many accidents resulting in its reputation as a "widow-maker." LeVier then showed everyone how it was done, as you said. The root of it was, however, lack of proper training. Most P-38 pilots had only a 100-200 hours flight time or so and prior to getting into the P-38 for the first time they closest they had was the "neutered" RP-322 (the British Lightning that was rejected and thus used stateside for introductory training) which had neither the turbos nor the counter-rotating props. So, put them in an airplane that had both and mistakes were frighteningly common.
 
A thought: are there enough new-builds to fit radar for a NF version, & butterfly away the P-61? (Looking at the cockpit pod, it looks bigger enough to add a true second seat.)

The Lockheed Swordfish, or Nosey, was used for research, but could have made a right fine nightfighter basis. It was described as having better diving characteristics.
I think the biggest problem with using the P-38 the platform for a designated Nightfighter was the poor option for RADAR installations. The P-38M used a RADAR dome hanging off the nose with a small AN/APS-6 radar. Something like the P-61 was much better because it was build with the radar installation planned from the start and so could accommodate the more powerful (and better resolution) multi-function SCR-720A radar. The AN/APS-6 is good for targeting a near-by target when you already know it is in the area but the SCR-720A had a search range of over 5 miles and so it could actual patrol and go on seek & destroy operations.
 
...
No, you are absolutely right. The first groups to get the P-38 had problems adapting to the single-engine behavior of the P-38 and it caused many accidents resulting in its reputation as a "widow-maker." LeVier then showed everyone how it was done, as you said. The root of it was, however, lack of proper training. Most P-38 pilots had only a 100-200 hours flight time or so and prior to getting into the P-38 for the first time they closest they had was the "neutered" RP-322 (the British Lightning that was rejected and thus used stateside for introductory training) which had neither the turbos nor the counter-rotating props. So, put them in an airplane that had both and mistakes were frighteningly common.

Hi, just a minor thing - the P-322-II was outfitted with 'handed' (= turning in opposite directions) engines, V-1710-27 (F2R) and -29 (F2L). No turbo, however - very suitable for 'training' altitudes (integral compressor was with 'slow' gearing), useless for fighter combat above 10000 ft even if it was tried. The P-322-II was produced or converted in 120 copies total.
 
I think the biggest problem with using the P-38 the platform for a designated Nightfighter was the poor option for RADAR installations. The P-38M used a RADAR dome hanging off the nose with a small AN/APS-6 radar. Something like the P-61 was much better because it was build with the radar installation planned from the start and so could accommodate the more powerful (and better resolution) multi-function SCR-720A radar. The AN/APS-6 is good for targeting a near-by target when you already know it is in the area but the SCR-720A had a search range of over 5 miles and so it could actual patrol and go on seek & destroy operations.

I wasn't so much suggesting the P-38 Swordfish as a primary night fighter, as implying it would be superior to the OTL P-38M, which was much similar to field modifications. That field modifications were performed means that such a night fighter was desired, and strangely, the superior P-61 had a much harder time convincing the AF of its desirability. The P-61 certainly had a longer gestation period.
 
he P-322-II was outfitted with 'handed' (= turning in opposite directions) engines, V-1710-27 (F2R) and -29 (F2L).
I wasn't aware of that. I was under the impression that the British wanted the Lightnings without "handed" engines for ease of maintenance. I do know that they went on to order standard specification P-38E's with the turbo-supercharged F2R/F2L engines as Lightning II's but due to the "tail flutter" issues in summer of 1941 they cancelled the order (costing Lockheed $15M!!). I will actually be addressing this in TTL starting in the next post. Given the current time in TTL, Lockheed and the RAF are currently in a legal dispute over whether the RAF still needs to buy the Lightning II's (a dispute which happened OTL) but with the supposed "tail flutter" already solved it may be possible to reach a compromise with the RAF. I am working through this right now and its possible ramifications.

EDIT: @tomo pauk, I did a little more research and it turns out we are both correct. The RP-322 was the restricted non-counter-rotating version and the P-322-II was the non-turbocharged but with counter-rotating. There were only 19 of the RP's in service and the rest of the British order (121 aircraft) were converted into P-322-II's.

Also being addressed is the XP-49 (I may bring up the XP-58 as well, but am undecided on that). Again, it is not possible to butterfly them away as they were already in development by fall of '41 and were intended to fill specific demands of the Air Corps and be built around specific powerplants (which were the biggest development hold-ups). However, with a better P-38 I am thinking it may be reasonable to redirect some resources back onto the P-38 to properly implement the improvements.
 
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Bravo on a well-told piece. The detail was enough I felt like I was right in the cockpit. Very well done. (I take it the quotes from the NACA were real ones?)
@phx1138 (was thx already taken? ;) ), Sorry, I didn't see the question before. Yes, the quotes are taken directly from the NACA report. I linked to it on the first post where I was describing the premise of this WI/ATL. It is actually a fascinating read and I highly recommend it for anyone with a love of the P-38. :)
 
I wasn't aware of that. I was under the impression that the British wanted the Lightnings without "handed" engines for ease of maintenance. I do know that they went on to order standard specification P-38E's with the turbo-supercharged F2R/F2L engines as Lightning II's but due to the "tail flutter" issues in summer of 1941 they cancelled the order (costing Lockheed $15M!!). I will actually be addressing this in TTL starting in the next post. Given the current time in TTL, Lockheed and the RAF are currently in a legal dispute over whether the RAF still needs to buy the Lightning II's (a dispute which happened OTL) but with the supposed "tail flutter" already solved it may be possible to reach a compromise with the RAF. I am working through this right now and its possible ramifications.

The RAF (and the French AF) specified the V-1710-33 (a.k.a C15) engines because of commonality with P-40s already ordered. Once France collapsed, UK took over the whole order (667 pcs total; cash & carry), and changed it to have the last 524 (= large majority) of their Lightnings to include F5R and F5R engines and turboes, basically the equivalent of the P-38F, powerplant-wise.
Problems with British order were several. One was that their 1st Lightnings will be delivered a year and half after the order. The non-turbo Lightning will be a fine fighter in 1940, still useful in early 1941, and useles vs. Luftwaffe's best in 1941 and on. In the meantime the USA entered the war (they need any fighter they can have), the Lighning is an expensive fighter for the RAF if the UK must buy it, while the Typhoon and Spitfire IX are expected to be at least as good in 1942. So cancelling og the British order in early 1942 cost Lockheed no Money (while saving British their own), since they have an even better costumer now that took over the better part of the British order, and wanted more. A second source in 1942?

Also being addressed is the XP-49 (I may bring up the XP-58 as well, but am undecided on that). Again, it is not possible to butterfly them away as they were already in development by fall of '41 and were intended to fill specific demands of the Air Corps and be built around specific powerplants (which were the biggest development hold-ups). However, with a better P-38 I am thinking it may be reasonable to redirect some resources back onto the P-38 to properly implement the improvements.

Holding my fingers that those two designs will be never built in metal - hey, a 440 mph P-38H in 1943!
 
Ch.2 - Design Meeting (Nov 1941)
Just a short update in the Narrative this time around. We are coming up on the U.S. entry to the war and I want to make sure I handle it properly. Until then, I give you some progress on the P-38 Improvement Program in a discussion between Lockheed Chief Engineer Hall Hibbard and the Chief Research Engineer, Kelly Johnson.

24 November 1941
Burbank, California, USA


Sometimes, bad news can be good news.

Hall Hibbard had just met with a representative from Curtiss-Wright who informed him that their experimental R-2160 “Tornado” engine was cancelled two days earlier. The R-2160 was the second engine intended for use with XP-58 after the Pratt & Whitney XH-2600 was cancelled the previous year. Without this engine the XP-58 project would be completely stalled pending yet another new engine selection.

The good news in all of this was that it freed up most of the XP-58 project teams for the short term—teams which could be re-directed to Kelly Johnson’s P-38 development group without impacting the Air Force’s demand for progress on the YP-49.

Hall Hibbard was pleased with the progress Kelly Johnson’s teams had made on the P-38. They had the full production line up and running and the new P-38E’s were being delivered to the Air. In addition, the reports of the early flight tests of the NACA modifications on YP-38 689 were more than promising. After reading the latest newspapers he only hoped they still had enough time to get everything squared away.

From Washington, the on-going negotiations with Japan sounded to be dissolving ever closer to war. The latest reports included a summary of the last proposal from the Japanese which would require the U.S. to practically abandon all of their South Pacific allies and holdings and no one thought the U.S. Government would agree to those terms.

There was even worse news coming from Europe where the German army had re-launched their offensive against Moscow and were even now closing around the Russian capitol. If the Soviet Union fell, then Britain would be left entirely alone and the entire might of the Third Reich would turn west toward the lonely island.

After dealing with TWA and Mr. Hughes—not the best way to start the Monday after Thanksgiving—Hall wanted a return to some sanity and Johnson was just the ticket. Hall had never seen anything quite like the way Kelly Johnson managed his teams and kept them organized. They all knew exactly what they needed to do and when to do it and when The Boss spoke up they listened and executed. In the past few years Lockheed had undergone a transformation from a small civilian design firm producing limited numbers of niche aircraft—such as the Electra—to a growing and military contractor producing the “Hudson” bomber and the P-38, one of the most advanced airplanes in the world, with numerous other projects in development. Hall had little illusion that Kelly Johnson was one of the main reasons and he had every intention of keeping Johnson on at Lockheed for as long as possible.

“Well, Kelsey is on board with us testing the NACA modifications on a combat ready airplane with armor, armament, and the new F2 engines; so, he is letting us keep 41-2009 as another development plane. We’ve already started altering the center fuselage and the engineers are developing the tooling to standardize the new wings which should be installed on oh-oh-nine in the next two weeks. Allison has our specifications for the new radiators, which should solve the coolant over-heat issues six-eight-nine has been having and has sent them on to their sub-contractor.” When he got going Kelly was all business, ticking through every item that needed to be discussed. “The oil radiators are another matter. The Bell units from the P-39 work fine but it seems there may be a bit of sourcing issue. Instead, we’re looking at the possibility of using the same ‘can’ radiators we already have but mounting them in the wing as NACA recommended.”

He continued down his list, “DuPont has had some men on-site working on the canopy revisions but we’ve been having problems with lensing on the quarter-shields. They apparently have some resources with I.C.I. who have been working on the newer British Perspex hoods so we’re hoping we can get something back soon. In the meantime we are putting the best Lucite DuPont has been able to give us on oh-oh-nine so we can at least start testing before Christmas.”

Hall nodded along before interjecting, “What about the XP-49?”

“The 522 prototype is still on schedule from our end. We are applying some of the NACA revelations into the new design but there is some question whether or not the new radiator set up will be able to accommodate the cooling requirements of the ‘X’ engine. If we ever get functioning engines from Continental we can test them but right now that’s in doubt. In the meantime, we are keeping the model 222 boom radiators and using the NACA 61-115 wing they tested instead of the leading edge extension.”

Kelly had been passionate about the XP-49, believing it to be able to live up to the full potential of his original Model 22 design, but he had become increasingly frustrated with the project as the engine requirements continued to change. First it was going to be designed around the Pratt & Whitney X-1800 “H-block” engine but when that project was cancelled last year they had to find another engine. Eventually they settled on the inverted-V Continental “Hyper Engine” which promised more than one horsepower per cubic inch. Now that engine, the XI-1430, had been caught in a development black hole with constant problems and the entire Model 522 project had been held back because of it.

“Hall,” Kelly continued, “with the new F5’s from Allison on their way I would like your permission to shift some of our resources from the XP-49 to the P-38 improvement projects.”

This was a surprising request to Hall. The P-49 was supposed to take to be a large performance improvement and that was estimated to depend largely on the engines, re-directing more resources back the P-38 could only be done if it can close that estimated performance gap. “Do you think the Allisons will be powerful enough to make up the difference?”

“They won’t be as powerful as the Continentals are supposed to be, but the F5’s are supposed to be rated to over fifty inches manifold pressure. We’re already planning on using them in the next P-38’s and I think with the other modifications we could render the 522 redundant.”

“Kelly, the Air Corps…” Damn! “…Air Force has commissioned the XP-49 and they expect delivery at some point. I can’t just pull the project.” Hall Hibbard did not follow the inner-politicking of the Military honchos but they seemed pretty adamant that there is difference between the old Army Air Corps and new Army Air Forces created a few months earlier. All the procurements were still signed by the Air Corps but apparently it was now a division of the new Army Air Forces which only added to Hall’s confusion. He was never sure which group he was dealing with or what name to use.

Hall continued, “I cannot give you any more from the P-49, Kelly.” His subordinate opened his mouth to protest but Hall cut him off, “But, I can give you some from the P-58.” Hall went on to explain the engine problems with that program and successfully mollified his young Chief Research Engineer with assurances that the P-38 Improvement Program would receive the resources it needed to succeed.
 
I have made a correction to the first narrative. The second section previously indicated that the test flight was from the Grand Central Terminal in Glendale when in fact it took place from the Lockheed Air Terminal in Burbank. I was confused originally because the OTL test flight ended when #689 broke apart and crashed in Glendale while returning to the airport. However, after finding a 5 November 1941 article from the LA Times about the crash I discovered that the flight did, indeed, leave from the Burbank facility and not the Glendale facility. I have altered the heading and the terminal reference in the narrative to reflect this.
 
The P-38L second seat looks cramped as hell. Radar operators would appreciate the extra room.
My thinking, too. (Tho it appears having them back-to-back would have helped, which seems not to have occurred to anyone...:rolleyes:)
I think the biggest problem with using the P-38 the platform for a designated Nightfighter was the poor option for RADAR installations. The P-38M used a RADAR dome hanging off the nose with a small AN/APS-6 radar. Something like the P-61 was much better because it was build with the radar installation planned from the start and so could accommodate the more powerful (and better resolution) multi-function SCR-720A radar. The AN/APS-6 is good for targeting a near-by target when you already know it is in the area but the SCR-720A had a search range of over 5 miles and so it could actual patrol and go on seek & destroy operations.
My thinking is, with the larger center nacelle (gondola? fuselage stub?:p), there's more room for radar, & it replaces some of the guns, or maybe those are repositioned.
No, you are absolutely right. The first groups to get the P-38 had problems adapting to the single-engine behavior of the P-38 and it caused many accidents resulting in its reputation as a "widow-maker." LeVier then showed everyone how it was done, as you said. The root of it was, however, lack of proper training. Most P-38 pilots had only a 100-200 hours flight time or so and prior to getting into the P-38 for the first time they closest they had was the "neutered" RP-322 (the British Lightning that was rejected and thus used stateside for introductory training) which had neither the turbos nor the counter-rotating props. So, put them in an airplane that had both and mistakes were frighteningly common.
Yeah, I was sure I had the faulty training & accident bits right, it was the correct response to a dead engine I got wrong.:teary: (It's been too long since I read the story...)

Also, thanks for "streamlining" the booms; those scoops always had me wondering what Johnson was thinking... (Then again, boundary layer scoops didn't exist yet...:p )

Re the XP-49: when the X1800 engines fail, would you contemplate switching to V3420s instead of the OTL Continentals?
@phx1138 (was thx already taken? ;) ), Sorry, I didn't see the question before. Yes, the quotes are taken directly from the NACA report. I linked to it on the first post where I was describing the premise of this WI/ATL. It is actually a fascinating read and I highly recommend it for anyone with a love of the P-38. :)
No worries, it wasn't a desperate need for info.:p Thx for the link to the paper; it's fascinating reading.

And no, I picked phx for "Pacific (theatre) History", knowing about the movie; I didn't like it, but I kind of liked the pun on it, for those in the know. (Around here, that's probably everybody.:p)

FYI for anybody who's liked the post about turbo blade lightening: I stole the idea from TurboUnion, which did the same on their RB199.
 
DAL-DC-3.jpg


With regard to the need for filleting, in 1934, a German, H Muttray wrote a paper on it. Bev Shenstone read it, and made a Spitfire, and the folks at Douglas read it and made a Gooney Bird. The folks at Lockheed didn't read it. The photo of the Lockheed is just the best I can find, but there's not much of a fillet at all. Unless it influences the tailplane, the fillet just lessens drag. If it does, it creates turbulence.
 
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