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Ken-Young's Avatar
Posts: 387 | Thanked: 1,700 times | Joined on Feb 2010 @ Cambridge, MA, USA
#2536
Originally Posted by billranton View Post
But a jet's thrust pushes against the air, [...]
Not really. A jet engine is a "reaction engine". It propels the aircraft forward by expelling mass, which must result in a forward force on the aircraft, via Newton's third law. It would work just as well in space, if it carried an oxidizer along with the fuel (which would make it a rocket engine).