By the way, there were also some very interesting developments during World War I.
by Gnome Rhone. Clerget or Oberursel - a so-called rotary engine.
'The crankshaft was attached to the aircraft's frame, and the engine block was also connected there.'
mit Zylindern dreht sich. Gemischführung über die hohle Kurbelwelle. Dhe
The propeller was securely screwed to the engine block.
I'll remember that, nobody has visited or read my link that I posted twice

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all good things come in threes: http://www.fh-friedberg.de/users/zima/konzept.html
Have fun exploring the VARIOUS types of circulation motors

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and even more fun and surprises with the rotary piston engine, which was new to me as well

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CU Gremlin.