Well it is a separate rocket version, it just doesn't take jet fuel. "Invite only" for the rocket version means probably less than 5 will ever be made, if that.
replyI strongly suspect that the invite-only version is the tech that was described in the demo, and differs from the $250K version by the size of the air tank and compression motor.
replyCold gas or not, these are still rocket motors.
replyWithout fuel or an oxidizer or combustion? Not really. It's compressed air, like an air rifle.
replyA rocket engine doesn't require combustion, it just requires expelling a gas to produce thrust, and that the engine not be air breathing. Most rocket engines use combustion to produce the high speed gases, but there are plenty that don't (water rockets, steam rockets, plasma rockets, and... cold gas thrusters as demonstrated by Tesla)
replyMotors don't need combustion, they just need to provide power. See electric motors or compressed air engines.
replyI doubt it is actual air. When compressing gas to 10,000+ psi and then running it through a rocket motor, clean/dry nitrogen is the way to go. Normal air has moisture, which can form ice, and oxygen which gets extremely reactive when heated.
replyAnd many a rocket scientist would be insulted by the comparison of a nozzled rocket motor to the simple pipe of an air rifle.
It takes genius to take rocket motors and cover them in cringe.
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