Re: 'Jet Belt': would that be possible?

Dear Simone
Yes, a 'Jet Belt' is possible and does work. The point is that the 
incoming air is accelerated in the jet engine. The relevant physical 
property is the "momentum" i.e. velocity times mass. A mass m of air enters 
the engine with a velocity v, say every second. This mass is ejected with a 
velocity much higher than v  and this results in an upwards force. All in 
all, it works just like a normal jet engine (the mass of the fuel plays an 
additional role).