have you ever been on an airplane in a half nap.. all sleepy and stupid, staring blankly at the back of the seat in front of you and you might just as well be in a waiting room at the dentist rather than one of 200 bodies smashed into this noisy jet when suddenly you remember that you are actually just a one hundred pound very breakable human, being flown through the clouds at hundreds of miles an hour, in a pretty heavy metal box that only stays up based on a limited amount of fuel that keeps ... shit i have no idea how it stays up ...

here! the Physics Factbook says it better...

All four models uses the jet engine which operates on the principle of Newton's third law of motion, which states that for every action, there is an opposite but equal reaction. A jet sucks air into the front, squeezes the air by pulling it through a series of spinning compressors, mixes it with fuel, and ignites the fuel, which then explodes rearward with great force out through the exhaust nozzle. This great rearward force is balanced with an equal force that pushes the jet engine, and the airplane attached to it, forward. Thrust is the force that propels an airplane forward through the air. It is provided by the airplane's propulsion system in this case by a jet engine.

that's how i feel right now. like i just realized how fast we're going. and how high up we are.