Ki-61 with DB601?
- Thread starter LordRain
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GregP
Major
You anwered your own question above, except for the logistics.
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It wasn't an exact copy of the DB601 that was developed, but a lightened version that the Japanese had serious problems with crankshaft issues. But to answer your question, you already answered it. As GregP posted.
Hello LordRain,
The answer is No.
The Germans had two different versions of the DB 601A engine.
The regular German standard as normally found in the Me 109E was the DB 601A-1.
There was also a version originally intended for export which was the DB 601Aa.
The A-1 had a more powerful supercharger and a little less power down low but had a higher critical altitude.
The Aa had a bit less critical altitude. It also had a higher power 1 minute take-off rating.
As the war dragged on, there were quite a few Me 109E equipped with the Aa engine which might be why some of the performance specifications for the 109E are not always in agreement. The Aa engine also ended up installed in other non-export German aircraft
Only the Aa was ever licensed to the Italians and Japanese. The Italians made some minor improvements on some versions.
The Japanese made some more significant changes (Kawasaki Ha 40) and arrived at an engine with very close to the same altitude capability as the DB 601A-1. From a performance standpoint, the Ha 40 was somewhere between a DB 601Aa and a DB 601A-1. Aichi also built a copy under license but I do not believe they did quite the same amount of work.
DB 601A-1 Critical Altitude 4500 Meters
DB 601Aa Critical Altitude 3700 Meters
Ha 40 Critical Altitude 4200 Meters
That is the long answer as I understand it.
- Ivan.
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Off the top of my head it was around 150 lbs., but give me some time to find that data in my stash on GD and HD's.
GregP
Major
I posted this once before, but maybe its time for a revisit. When I was working at Joe Yancey's Allison shop, he talked with a guy who knew of 3 Ki-61s being worked on in the U.S.A. (I seem to recall the southeast U.S.A., maybe Georgia or Alabama ...) and we heard a claim that sort of makes some sense in light of history.
It seems one of the Atusta Ha-40 engines was pulled apart and examined pretty thoroughly by a knowledgeable pilot/mechanic who said that the Ha-40 was missing an oil return line from the nose case back to the crankcase-oil pump accumulator. That would account for the constant trouble with the Ha-40 and allow for about an hour to an hour and a half of running before the engine might fail. What was postulated at the time (around 2014 or so) was that the Japanese had simply missed the oil return line on the drawing, making the Ha-40 a chronically problematic powerlant. It was intimated that all that was need was to bore the reurn line and give the oil a channel, and maybe the Ha-40's reliability issues would go away.
I can't vouch for the accuracy of this claim at all, or even make an intelligent assessment of the possibility as I've never even seen an Ha-40. But I CAN all say that anyone having access to an Ha-40 that might be undergoing overhaul COULD check to see that all the oil returns in the nosecase of a DB 601 were actually there in the Ha-40 ... that would settle the claim.
Unfortunately, I don't know who, if anyone, still has a Ki-61 in the U.A.A that still might be being worked on at thius time. But the claim of the missing oil return line was bandied about about 6 years or so back. I thought this might be of some interest ... but the Ki-100 was a better airplane than the Ki-61 anyway. Just a possible interesting rumor to think about that may never be settled one way or the other.
It seems one of the Atusta Ha-40 engines was pulled apart and examined pretty thoroughly by a knowledgeable pilot/mechanic who said that the Ha-40 was missing an oil return line from the nose case back to the crankcase-oil pump accumulator. That would account for the constant trouble with the Ha-40 and allow for about an hour to an hour and a half of running before the engine might fail. What was postulated at the time (around 2014 or so) was that the Japanese had simply missed the oil return line on the drawing, making the Ha-40 a chronically problematic powerlant. It was intimated that all that was need was to bore the reurn line and give the oil a channel, and maybe the Ha-40's reliability issues would go away.
I can't vouch for the accuracy of this claim at all, or even make an intelligent assessment of the possibility as I've never even seen an Ha-40. But I CAN all say that anyone having access to an Ha-40 that might be undergoing overhaul COULD check to see that all the oil returns in the nosecase of a DB 601 were actually there in the Ha-40 ... that would settle the claim.
Unfortunately, I don't know who, if anyone, still has a Ki-61 in the U.A.A that still might be being worked on at thius time. But the claim of the missing oil return line was bandied about about 6 years or so back. I thought this might be of some interest ... but the Ki-100 was a better airplane than the Ki-61 anyway. Just a possible interesting rumor to think about that may never be settled one way or the other.
Hello GregP,
As I mentioned, both Aichi and Kawasaki license built DB 601 type engines.
The Aichi version was called the Atsuta. The Kawasaki version was called the Ha 40.
They were not the same engine and the Japanese were very much noted for not sharing much information between services and probably didn't do any better between companies.
The Atsuta was installed in the Aichi Seiran floatplane and in the Yokosuka Suisei torpedo bomber and probably others that I don't remember offhand.
- Ivan.
As I mentioned, both Aichi and Kawasaki license built DB 601 type engines.
The Aichi version was called the Atsuta. The Kawasaki version was called the Ha 40.
They were not the same engine and the Japanese were very much noted for not sharing much information between services and probably didn't do any better between companies.
The Atsuta was installed in the Aichi Seiran floatplane and in the Yokosuka Suisei torpedo bomber and probably others that I don't remember offhand.
- Ivan.
Japanese Wiki explains DB 601 in Japan like this -
"Around 1935 (Showa 10), IJN and IJA decided the license production of DB 600.
IJN scheduled Aichi but IJA thought Kawasaki for production. After discussions between two, as Aichi agreed to undertake the production, negotiation for the license with Daimler-Benz was unified to Aichi only. At this point, IJA was going to use Aichi's products, of course. However, during this negotiation, IJN and IJA had purchased Heinkel He 118 dive bombers which were equipped with DB 600 for evaluation. To know this, Daimler-Benz became distrustful of the Japanese side for obtaining DB 600s before signing the contract. Daimler-Benz requested Japan to revise the license contract. Under this situation, negotiation had been stranded but the contract was agreed anyhow by the mediation of German Ministry of Aviation finally. All issues seemed to have been resolved. However, during the negotiation, more advanced DB 601 had been developed. As DB 601 showed higher performances, Japanese side wondered if they should produce DB 601. Daimler-Benz advised that the license covered DB 600 only and suggested new contract for the 601. In the year of 1939, the production of Japanese military aircraft rapidly increased due to the influence of Sino-Japanese War. IJN and IJA reassessed the production capability of Aichi Aircraft and concluded that it would be difficult for Aichi solely to fulfill the increasing demands from IJN and IJA. Based on this conclusion, IJA decided to let Kawasaki Aircraft produce DB 601 and Kawasaki began negotiation with Daimler-Benz.
It is often said that IJN and IJA produced same engine separately because they were not friendly. However, truth was that they needed more engines immediately though it should be criticized that they did not research Aichi's capability well before the negotiation."
Source: ハ40 (エンジン)
"Around 1935 (Showa 10), IJN and IJA decided the license production of DB 600.
IJN scheduled Aichi but IJA thought Kawasaki for production. After discussions between two, as Aichi agreed to undertake the production, negotiation for the license with Daimler-Benz was unified to Aichi only. At this point, IJA was going to use Aichi's products, of course. However, during this negotiation, IJN and IJA had purchased Heinkel He 118 dive bombers which were equipped with DB 600 for evaluation. To know this, Daimler-Benz became distrustful of the Japanese side for obtaining DB 600s before signing the contract. Daimler-Benz requested Japan to revise the license contract. Under this situation, negotiation had been stranded but the contract was agreed anyhow by the mediation of German Ministry of Aviation finally. All issues seemed to have been resolved. However, during the negotiation, more advanced DB 601 had been developed. As DB 601 showed higher performances, Japanese side wondered if they should produce DB 601. Daimler-Benz advised that the license covered DB 600 only and suggested new contract for the 601. In the year of 1939, the production of Japanese military aircraft rapidly increased due to the influence of Sino-Japanese War. IJN and IJA reassessed the production capability of Aichi Aircraft and concluded that it would be difficult for Aichi solely to fulfill the increasing demands from IJN and IJA. Based on this conclusion, IJA decided to let Kawasaki Aircraft produce DB 601 and Kawasaki began negotiation with Daimler-Benz.
It is often said that IJN and IJA produced same engine separately because they were not friendly. However, truth was that they needed more engines immediately though it should be criticized that they did not research Aichi's capability well before the negotiation."
Source: ハ40 (エンジン)
GregP
Major
The engines we were told about were Ha-40s in Ki-61's from Kawasaki. I am under the distinct impression that the Atsuta and Kawasaki Ha-40 were essentially interechangeable, but it is also distinctly possible that one has a fault the other doesn't, seeing as how they were produced by different companies that likely didn't share tooling.
