Excuse me!!!

[jrpilot]

But how do Turbojets and Turboprops work?...Does the thrust somehow bounce of the air? I really don't understand.... :-/

[born_2_fly]

Can you be more specific, how do you mean? How do the engines produce the trust or how it has an effect on the air to produce forward movement?

[OTTOL]

http://en.wikipedia.org/wiki/Jet_engine

A turboJET has a single inlet and exhaust and uses compressed, heated air to push the airplane through the air

A turboFAN- is a turboJET that is atached to a large internal fan. It uses a combination of thrust from the Jet and the Fan. The large blades that you see at the inlet of most modern jets are the "driven" fan. Ambient(temperature) air is driven through the outer(bypass) section of the engine. ( in fact when a turboFAN is running you can safely hold your hand behind the outer exhaust flow!)

A turboPROP-

[chomp_rock]

And they work on the principle of this most important law: Every action has an equal and opposite reaction.

[Tequila Sunrise]

The Vernoulii effect causes thrust taken in one end to be accelerated and lowwered in preasure V1P2. This i caused by intake air entering into a funnel, the same volume of air being taken into the intake must pass through a narrow channell and achieves this by accelerating, this air is then ignited and expands rappidly, it is then expelled through the exhaust whilst trying to expand causing it to push against the free stream air.

I should probably rewrite that as it aint worded too well but I'm off to bed  ::)

Craig  8)

[Nexus]

His name was Bernoulli btw  (You just spelled the name worng, no biggie)  

[Rocket_Bird]

Like what OTTOL said.

A turbojet consists of simply compressing air and accellerating that air back the exaust.  As Force equals mass times accelleration, the more air you accellerate, the more force (thrust) you will have.  Also you can think of it as a balloon, letting all that air out the back gives you a force at the front of the balloon pushing it forward.

A turbo prop works on a similar principle, still compresses air, but the energy you have you use to drive a propeller giving you longitudinal thrust through the use of airfoils