Talk:Lockheed P-38 Lightning

WikiProject Military history

(Rated B-Class)

This article is within the scope of the Military history WikiProject. If you would like to participate, please visit the project page, where you can join the project and see a list of open tasks. To use this banner, please see the full instructions. B This article has been rated as B-Class on the quality assessment scale. Additional information... This article has been checked against the following criteria for B-Class status: Referencing and citation: criterion met Coverage and accuracy: criterion met Structure: criterion met Grammar: criterion met Supporting materials: criterion met Associated task forces (general topics): Military aviation task force Associated task forces (nations and regions): United States military history task force Associated task forces (periods and conflicts): World War II task force

compressibility stall?

In the chapter titled Design and development, a link titled compressibility stall connects to a page titled Compressibility. On that page, while there is (what appears to be) a good discussion of compressibility of fluids (including that of air, in relation to flight), the specific term compressibility stall, as used in this P-38 Lightening article, is never defined. It might be good to do so. I have no education or experience in this area, so I'll leave this as a suggestion to a writer more informed than I. Fagiolonero 23:50, 21 March 2007 (UTC)

I've got another issue with the claim. I've always understood the fillets were to solve flutter & had nothing to do with compressibility, which was solved by the dive flaps. Can somebody confirm or correct? Trekphiler 22:44, 18 August 2007 (UTC)

Trekphiler, I've taken a shot at separating compressibility and buffeting. Flutter is a great description of what was experienced by test pilots but is technically incorrect a term for the P-38 since it's related to the kind of flexing of the empennage you'd see in a wood and fabric plane. The P-38's tail was strong enough for Kelly Johnson to say "no P-38 ever had 'tail flutter'." Binksternet 23:41, 20 August 2007 (UTC)

Outstanding, Binksternet. That's the best explanation of the problem in a handful of words I've ever seen. And it actually explains how the flaps worked, which I don't think I've ever seen before. I can take this page off my watchlist (unless some dimwit puts back XP-49s as "variants" again...) Trekphiler 13:23, 21 August 2007 (UTC)

Thanks for the positive review. I wonder if I'm up to the task of writing an article about how compressibility plagued the development of P-47s, P-51s and just about every other hot airplane in WWII? Mach speeds were being approached and accelerated airflow over certain parts of the airframe was getting out of control. One source I have says compressibility accidents killed more pilots in other airplanes than in P-38s. It's just that with P-38s the problem was better documented. Binksternet 15:45, 21 August 2007 (UTC)

Watching an interview with a P-38 pilot on YouTube, he talks about compressibility and how to handle it. According to him, you just rode the plane down to 10,000 feet and compressibility ceased to be a problem. The elevators and ailerons regained authority and you just pulled out of the dive. 71.239.184.168 (talk) —Preceding undated comment added 20:31, 26 June 2012 (UTC)

Merlin Powered P-38 Part 2

Which naturally segues into this topic. An earlier discussion ended with comments that a conversion of the P-38 from the Allison V-1710 to the Merlin would not have had any advantages and would have disrupted production. "Vees for Victory" (which I have described as an apolegetica for the V-1710) comes to the same conclusion. The Allison did have advantages over the Merlin, mainly its greater fuel efficiency (see above comments on how that was accomplished - its manifold was designed to provide a ram-effect and ran on leaner mixtures which allowed for removal of the backfire screen - downside was that this caused an uneven fuel distribution and detonation problems at the high altitudes of the European bombing campaign).

However, the obvious advantage of such a conversion is never pointed out, which is that the P-38s could have been flying in Europe at high altitude and full combat power without blowing up. "Vees for Victory" concedes that ultimately, it was objections from Allison that caused the USAAF to quash beginning efforts to do this conversion. "Allied Aircraft Piston engines Engines of WWII" states the same thing - objections from Allison quashed this effort at converting a P-38 to the Merlin.

And the previous Merlin P-38 discussion was incorrect - the P-38K was not the Merlin engined P-38. The Merlin P-38 never had a designation as it was never completed, as far as I can tell and there are only stories of its existence. DarthRad (talk)

Changing the engines to the Merlin may have conferred some advantages but the downside would have been the extensive re-design of the nacelles and cooling systems necessary. The Merlin was supercharged and had no need of the ducting that the turbocharged Allisons had and so much of this pipework could have been removed. This would have saved some weight making the aircraft lighter, which in itself would have improved performance. However, ...

... for the exercise to have been useful the two-stage Merlin 60-series would probably have been needed, and that would have been good for an altitude of around 40-44,000ft, unfortunately this would have exacerbated the compressibility problems that had already plagued the Lightning, as the speed of sound becomes lower the higher one flies. So at the increased altitudes made possible by the new engines the aircraft would just have suffered the effects of the sound barrier even earlier (at lower airspeed) than the Allison-engined ones. The only way to resolve this would probably have been to design a new, thinner wing, with a higher critical Mach number. This was unlikely to happen as it would probably have been better just to start again with a clean sheet of paper.

Lower down the Merlins would probably have conferred no useful advantages (apart from reliability) over the Allisons anyway, with the possible exception of the Merlin being able to use 150 grade fuel. — Preceding unsigned comment added by 80.4.57.101 (talk) 18:12, 22 October 2011 (UTC)

There's a 1943 Lockheed information film; "P-38 Flight Characteristics" on YouTube that some of you might like here: [1] — Preceding unsigned comment added by 80.4.57.101 (talk) 20:06, 1 April 2012 (UTC)

Hispano-Suiza HS.404

As a layman in these topics it strikes me as contradiction what's written here and Hispano-Suiza_HS.404#US_production. According to that article, the autocannons manufactured in the US never worked good enough to be put into use. So where were the 20 mm's for the P-38 coming from? --Pjacobi (talk) 10:52, 28 October 2012 (UTC)

The Lightning experienced in-flight failures of the autocannon, but not as much as some other aircraft with the same gun. Perhaps it was the central placement, subject to less g-force during aerobatics. The autocannon worked good enough if the pilot attacked with a straight approach, not so good in a swirling dogfight. Binksternet (talk) 14:44, 28 October 2012 (UTC)

Distance units in Lindbergh section

Under Charles Lindbergh are given stats on extending the range of the P-38.

I wonder about the use of "miles" --- indicated airspeed on an aircraft is calibrated in nautical miles per hour (knots), not statute miles per hour. Hence the mph figure cited is actually nm/h, or knots. The problem is compounded in calculating the equivalent speed in km/h. As presented here, it is based on ~1.60 km, which is per statute mile. If the miles are nautical, then the proper conversion is 1.85 km. In which case, the equivalent metric speed for 185 knots should be 342 km/h, not 298 km/h. In addition, the 2.6 mpg figure should be 2.6 nmpg, or 2.6 nm/gal. PhuDoi1 (talk) 15:37, 27 November 2012 (UTC)

The P-38, like all US Army airplanes of that time, did not show nautical miles on its speedometer. The mileage figures are fine as they stand. Binksternet (talk) 17:23, 27 November 2012 (UTC)

The use of the knot as a measure of speed in aviation did not become widespread on either side of the Atlantic until after WW II. Prior to this almost all non-metric air speed indicators would have been calibrated in miles-per-hour. The only exception I am aware of was the UK Fleet Air Arm which used knots, it making navigation easier over the sea as all nautical charts are marked using the nautical mile. IIRC, the knot entered western international aviation use in around 1946, possibly due to the ICAO.

So if you see speed figures for a wartime aircraft given in knots then someone would have needed to have converted them, as they would almost certainly have originally been quoted in miles-per-hour. — Preceding unsigned comment added by 80.7.147.13 (talk) 11:03, 16 February 2013 (UTC)

P-38 shot down by a Fiat CR.42 in Croatia

Hello, I found in two Osprey books this information about an air combat between the P-38 and the Fiat CR.42. The information is important as it is one of the last if not the last dogfight of P-38 in Europe and moreover it saw the last kill by a biplane fighter in history. Binksternet deleted it regarding as "not important and trivia". I am still waiting he explain me why. I do ask for consensus to keep this information in the article even if I understand it could hurt the feelings of someone. Here is the text: At least occasionally, the P-38 was still employed in combat in European theater. On 8 February 1945, P-38 Lightnings of the 14th Fighter Group (FG) attacked Luftwaffe Fiat CR.42LWs from Nachtschlachtgruppe 7, bound to strafe partisans in Croatia, Yugoslavia. The American fighters shot down three Fiat biplanes, but two P-38s did not return to base, one of them claimed by a German pilot. So the P-38 was most probably the last kill of a biplane fighter in history. Gian piero milanetti (talk) 21:34, 31 January 2013 (UTC)

I'd say it was more relevant to the CR.42 article than this one.GraemeLeggett (talk) 21:50, 31 January 2013 (UTC)

The problems I have with the addition are twofold: The claimed kill is not confirmed, so is unable to support an absolute statement about the last biplane kill in the world, and the emphasis on one unimportant action is not worthy of the larger topic. Binksternet (talk) 02:49, 1 February 2013 (UTC)

Not confirmed? It seems to me that saying so we are in the "kingdom of personal opinion": there was one claim and two losses! How can you say that is not confirmed? And where is the emphasis? We are speaking of few lines in front of an article very very long. Still, I think these are personal opinions, so the contribute should be put back. Gian piero milanetti (talk) 06:05, 1 February 2013 (UTC)

By "not confirmed" I mean exactly that. The kill was claimed by one German pilot, no name, no unit, his aircraft type not specified, the kill not confirmed. Binksternet (talk) 13:26, 1 February 2013 (UTC)

You should read before deleting: in the contribute were specified the unit and the name of both aircraft involved. Acting in that why you do not help to write a good encyclopaedya, in this case you do not seem to be driven by the interest of helping creating a reference article. May be You can get consensus from some other people here, but that does not mean that you are right, you simply know how to districate yourself in the labyrinth of wikipedia. As an aviation historian I do not appreciate what you are doing here. Gian piero milanetti (talk) 14:41, 1 February 2013 (UTC)

You're taking this rather personally, and getting rather personal in your responses. Please tone it down.

As for the issue at hand: I tend to agree with Binksternet. The claim is dubious and the incident not significant enough to warrant mention in this article. That's a matter of exercising good judgement in trying to keep Wikipedia usable. Wikipedia is not an indiscriminate collection of information.. --Yaush (talk) 14:57, 1 February 2013 (UTC)

Why you say that the claim is dubious? If so, the articles of pilots in wikipedia are full of dubious claims (Beurling's, Pattle's etc) but still the claims are there... And why you suggest me to read the article WP: DISCRIMINATE? You mean that I am trying to do an indiscrimante collection of informations? And this is not Your personal point of view?! Ok, let's stop it, I give up, I know how it works, two or three people agree about something and this is called consensus... that's one of the major shortcomings of wikipedia. I do not insist, thanks God I have books where I can write history. Gian piero milanetti (talk) 17:24, 1 February 2013 (UTC)