Most Beautiful Aircraft of WW2? (1 Viewer)

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So much for heresay stories!

I've never seen a breakdown of the Atsuta, but I understand it was basically a Japanese copy of the DB 601. That said, I can't confirm or deny it; it's just what I've read. Some of what I've heard anecdotally has proven to be true, some not. I'm around warbirds at least a couple to times a week, so not too much BS gets through but, inevitably, some does.

Live and learn, huh?
 
Hi Greg,
Yes, the Japanese versions of the DB 601 and 605 look quite different in detail. They seem to have taken the basic design's and re-engineered them, rather than copy exactly.
I think I have to modify my details about the DB 601/605 oil scavenge path slightly. Looking very carefully at other detailed pictures, there is another link route for scavenge oil from the crankcase main scavenge drain trough in the V between the cylinders. That trough usually drains crankcase scavenge oil to the rear of the engine where it runs down in branch pipes to the rear of each cam cover and the scavenge pumps. However, there are passages at the forward end of the trough that lead out into the front reduction case. These passages are hidden behind that steel plate baffle that stops the oil flowing forwards hitting the large reduction gear. This oil path would normally suit prolonged descent angles, where some oil would be draining forward and would otherwise pool in the forward end of the crankcase. Although the scavenge pumps are at the rear of the cam covers, there is a suction pipe inside each cover that would lift this oil back to the rear of the cam cover and through the scavenge pumps. So, if these forward crankcase drain paths from the trough were blocked, or not there, I think it would mean in a prolonged nose down attitude that the forward part of the crankcase could become flooded with oil as none would pass out through to the reduction gear drain path and the angle would stop it flowing back and out. Overall, this could possibly be what your friend mean't to describe? The result of not having the forward drain path holes would not be trapped oil in the reduction gear area but more a problem of crankcase drain oil trapped in the forward area of the crankcase in a nose-down attitude.
I think you can see the situation if you look carefully at the diagram.
Cheers
Eng

47_2981.jpg
 
Only problem with that is the Japanese were very good with radials and not so hot with inlines.

They never got the Atsuta (Japanese DB) right and a friend of mine who SHOULD know since he flew about 15 Atsutas after the war in Ki-61s, said it was because they missed an oil return line from the nose case. He claims the Atsuta would run for about an hour or so and then the nose case was full of oil and started to overheat while the rest of the engine was low on oil, too. Not too sure of he was right, but the Japanese radials were pretty good as far as reliability ... well, most of them. The Homare was OK when it was built right, but constant bombing made that problematic, to say the least, coupled with low stocks of critical metal raw material.
Atstuta engines were made at Aichi, for the needs of the Navy (mostly for the Judys).
Kawasaki was making Ha 40 engines for the Army, including what the Ki-61 gotten.
 
As far as I know, the Atsuta and the Ha40 were basically the same engine (Japanese DB 601a) made by two different plants and the differing designations were because one was IJN and one was IJA, who never cooperated on anything with one another. Is that the way you see it, Tomo?
 
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Certainly, I find the Japanese DB engine based developments complicated. A good book is Goodwin and Starkings Japanese Aero Engines 1910 to 1945. The developments were made by Aichi and Kawasaki but, they are separate, complicated and quite different. Really complicated and I find understanding the chronology difficult, even with the book.

Eng
 
The P-51H and P-82B/XP-82 IMO look properly aggressive, and the P-51D looks like a tailored suit that Agent 47 from the Hitman games would wear as his signature suit. Combine them and you get the XP-51F/G. Small photos, but photos of them are relatively rare (most of the good ones are probably at Boeing's Archives, though San Diego Air and Space Museum has some good HQ ones, too), certainly of them in actual testing conditions.

XP-51F on run up (source, cropped image from David McLaren's North American P-51H Mustang/Air Force Legends 209, credited to North American Aviation):

North American P-51H Mustang_0002-modified.jpg


XP-51G with an oil overfill issue (source, XP-51G Facebook page, possibly from the NAA/Boeing Archives):

62384_163682846979979_813435_n.jpg
 
The P-51H and P-82B/XP-82 IMO look properly aggressive, and the P-51D looks like a tailored suit that Agent 47 from the Hitman games would wear as his signature suit. Combine them and you get the XP-51F/G. Small photos, but photos of them are relatively rare (most of the good ones are probably at Boeing's Archives, though San Diego Air and Space Museum has some good HQ ones, too), certainly of them in actual testing conditions.

XP-51F on run up (source, cropped image from David McLaren's North American P-51H Mustang/Air Force Legends 209, credited to North American Aviation):

View attachment 758024

XP-51G with an oil overfill issue (source, XP-51G Facebook page, possibly from the NAA/Boeing Archives):

View attachment 758025
On this I must AGREE!
 

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