Personnel Airdrop Simulation

We develop an object-oriented simulation that models the airdrop mission of a U.S. transport aircraft, the C-1 7 Globemaster III. The simulation, written in MODSIM III, is based on three basic object types: an aircraft, a wake vortex, and a paratrooper. The aircraft object provides the required aerodynamic constants for simulating the wake vortices generated off each wingtip; the vortex object includes velocity field and decay models as well as a position algorithm; and the paratrooper object implements a 6-degree-of-freedom trajectory model. Using the simulation, we generate vortex encounter information for various formations and wind conditions, and quantify the associated risk of paratrooper/vortex encounters in a potential en counter rate. Time over the drop zone is a primary concern in any airdrop operation, and the results of this analysis form a tool that allows the ground com mander to assess the risk involved in decreasing that time.