[Jukka Juutinen]

It is mentioned in this thread that lack of sourced prevent this and that topic to be studied. But, let's remember the recent book Secret Horsepower Race. Many, many times before that book one could hear claims that that topic lacked sources. Then came Calum Douglas who dug deep into the archives and found mountains of new information creating a masterpiece. After that case one may really ask that how much untapped material still is to be found on other Luftwaffe topics in the archives, but researchers have not delved thus far deep enough. And in the case of the Secret Horsepower Race, another crucial aspect pertaining to the authoritativeness of the book is that he is an engine-designer himself.