Aircraft Engine Historical Society

Roundel · 15 October 2005, 08:20 PM

This group has a website:

http://www.enginehistory.org/

The pre-1925 section has a link to an animated diagram of the workings of the Gnome rotary engine:

http://www.enginehistory.org/before_1925.htm

19 October 2005, 05:10 AM

That was very interesting. But they show the crankshaft off center....?????

FlyXwire · 22 October 2005, 03:56 PM

Yes, the crankcase and cylinders spin on a bearing race at the rear of the rotary engine, and the internal crankshaft is offset from the centerline of the external casing's rotation, thereby causing the rods & pistons to move into and out of the cylinders as they rotate.

If the piston rods rotated around the same axis as did the outer crankcase, then no internal stroke would be enabled (the rods and pistons would just spin static around the centerline with the rest of the engine).