Hi there. I am trying to create a realistic physics simulation for testing thrust based hovering vehicle designs and i am stuck. I understand basic physics like moment of inertia and forces and the like but thrust is something i am having trouble with. Currently if i place a vertical thruster at each corner of a rectangular craft, when the thrust force overcomes the weight of the craft it just kind of floats streight up forever. As it is, the thrust force is just a variable being incremented and added to the rest of the force calculations. The thrusters are supposed to be propeller style things expelling air at high speed. The main problem is that i expected the craft to reach an equallibrium for a given amount of thrust rather than just floating on out into space. There is a huge hole in my knowledge of physics here and if you can provide any links to good resources or have any comments of your own, i would be most grateful for any help.