I've wanted to know more about any Japanese aircraft that could have been potential sources of parts found on Niku, but records of Japanese aircraft lost during the war are very poor. There were lots of Japanese aircraft lost in the Pacific theatre during the war but there are very few details of locations, types or numbers. Further complicating the effort is an almost complete lack of remaining examples to look at – most were scrapped after the war and few records even of those were kept. Yet further complicating the effort is an almost total lack of design details. To look into that further I obtained a copy of “Japanese Aircraft 1910-1941” (R. Mikesh, S. Abe, 1990), which has been interesting to look through. The 1930’s were a time when Japan was working with lots of other country’s aircraft manufacturers, buying examples of aircraft, building licensed copies of aircraft and engines, and working with foreign companies to design their own aircraft. All major aircraft companies are mentioned in the book – Douglas, Lockheed, Boeing, Northrop, Vought, Beechcraft, Piper, Bristol, Glouster, Avro, Dewoitine, Messerschmitt, Junkers, Fokker, Wright, Hamilton-Standard, Rolls-Royce, Mercedes, BMW, etc, just to name those mentioned on a dozen pages. Most seemed to have found use in the Sino-Japanese war, and most weren’t suitable for long over-water flights. The few that could have been used over the Pacific are intriguing to think about.
Ric mentioned the Export Control Act, July 2, 1940, as likely to have been the last date any Alclad might have been imported into Japan. Aircraft made immediately prior to that date could obviously have used Alclad, but the 2-2-V-1 artifact appears to be hand-stamped, indicating that it was from an early run, prior to the major buildup to WWII.
The book does not specifically mention “ALCLAD”, but I found one mention that the 1936 Nakajima Experimental LB-2 Long-range Attack Aircraft used “ALC17ST aluminium with a B-2209/2218 aerofoil employed the structural design of the Douglas wing…” (pg 235). There was only one example built, inspired by the licence-built DC-2’s that Nakajima was building, and it was scrapped in 1941.
Nakajima built 5 DC-2’s between 1936-37. The Allied designation was “Tess”, and they were known to have seen service in China.
Of special interest to me was the
photo of some Kawanishi H6K “Mavis” wreckage in New Guinea that clearly showed the “ALCLAD” production stamp. (update - the photographer has confirmed that the photo is of a B-24 and needs to be corrected)
Ric posted “…Although I haven't found aluminum specifically mentioned, the Export Control Act of July 2, 1940 almost certainly shut down all export of aircraft aluminum to Japan, even from 2nd party distributors. The AN-A-13 labeling on the Mavis (Kawanishi HK6) appears to be "rolled on" (aligned with the edges of the sheet) whereas the labeling on 2-2-V-1 was (in the opinion of Alcoa engineers) was hand-stamped and probably from an early and/of small production run.
So it looks like the AN-A-13 designation predates December 7, 1941 and probably predates July 2, 1940, and the artifact was probably hand-stamped earlier than that. I think our hypothesis is okay. (whew!)”
So, this long story seems to indicate that the Japanese were using ALC17ST as early as 1936, and likely stopped getting any new stocks of Alclad after July 1940. They also built flying boats using production Alclad that saw service during the war. (update - this statement is no longer supported - see the update comment above)
What are the chances of an early (hand-stamped) piece of Alclad being found on a Japanese aircraft wreck?
What Japanese aircraft could possibly have been in the Gardner area?
Are there any examples or detailed information that would help identify or rule-out 2-2-V-1 as being Japanese built?
What other questions need asked?