www.pulse-jets.com

Cyclogyros come close, although their rotor axes are perpendicular to the direction of flight.

lhttp://hilltop.bradley.edu/~spost/cyclogyro.html

They look somewhat like flying grain harvesters.

Now the Lockwood makes me wonder what if you put a tube in front of the intake but leaving a gap, flared pretty much like that of the intake, with a closed end, so the blast would bounce back into the intake at the proper time, and cram in some more air? Maybe half the intake tube length? Tuned with...

Just curious. Does the detonation cell size change with pressure?