Trajectory Modeling of a Parafoil in Motion Using Analytically Derived Stability Derivative at High Angle of Attack

(Abstract) Parafoil and payload system are light weight, fly at low speed and provides soft landing capability. The parafoil-payload system flight dynamics requires a 9-DOF model unlike the 6-DOF model, since this system is a two-body dynamic system. This paper attempts to formulate the aerodynamic model for parafoil-payload system and derives the detail analytical expression for the longitudinal and lateral directional aerodynamic derivatives at high angle of attack. The 9-DOF simulation studies were carried out for a chosen parafoil-payload system using the derived aerodynamic derivatives.