"cavelamb himself" wrote

In addition, there are two fans - side by side.
I believe the torque reactions would be in fore/aft pitch.

Hmm?

I don't think torque is going to be a show-stopper. I believe these are two
counter-rotation, fixed pitch propellers, and the only collective (so to
speak) is the RPM of the engine. The RPM stays mostly constant, and changes
slowly, so the fore and aft reaction should be pretty slight.

I don't see that this thing will work without some kind of fly by wire, or
more precisely, some type of electronic stability system. It is common
practice for remote control helicopters; a couple rate gyros, and a
connection to a couple servos to keep things from wobbling out of control so
much.

Another problem could be the pilots position on the machine. With the real
jet pack, the pilot's legs and free to move around to allow the pilot to
give some "body english" small corrections to the flight path. That does
not look to be possible, for this particular (S)mall (M)otor (U)pwards
(R)otor (F)lyer, or SMURF, for short. ggg
--
Jim in NC