how is thrust calculated?

[rubber314chicken]

title says it all. how would I calculate thrust if I knew the rpm, airspeed, engine hp and torque, and the prop size and pitch?

 

[Steve]

The old-fashioned way would be to tie a fish scale to the tail, but engineers now use equations...

http://www.heli-chair.com/aerodynamics_101.html

Note that this example gives theoretical thrust, excluding efficiency losses.

A more rigorous treatment is available at

http://www.mh-aerotools.de/airfoils/propuls1.htm