Math. Modeling for Wind turbine's loads & Aerodynamics

Dear all;
How can i find the equations that the FAST used it for a mathematical modeling of the wind turbine’s (specially on blades) loads and Aerodynamics?

Dear AbdelRahman.Elkattan,

Information on the FAST theory basis is provided in the following forum topic: http://forums.nrel.gov/t/coupled-blade-modes-in-fast/314/1.

Best regards,

Dear Jason;
Thank a lot for your support and your speed response