Internal Propulsion

[broli]

In the device with the fly wheel and the bullet, you suppose their is a momentum m*v to the right. This is true only during the short period when the bullet flies and carries an opposed momentum (leaving at rest the center of mass of the whole device). It is false when the bullet strikes the paddle of flywheel because at this moment the whole systems begins to  rotate on itself in order to maintain both linear and circular momentum of the whole device.

I do not agree with that statement. You can mirror the setup to have 2 bullets and two fly wheels. In order to cancel rotation about the main systems center of mass. But you will still end up with some linear momentum converted into rotational momentum which means the the total linear momentum of the bullets is not converted back all back to linear momentum.

I attached such system and I also included an extra bullet attached to the wheels for balancing to prevent centripetal/centrifugal force action.

[Cherryman]

http://www.youtube.com/user/YbborNetsrek#p/u/25/Nr5qAyJ_30A