Dynamic Simulation and Analysis of Military Vehicle Airdrop Rigged Item Landing

Landing legs of military trailers were being damaged during airdrop testing. A dynamic analysis of a 5-ton capacity military trailer, fully rigged for an airdrop procedure, was performed using DADS software in order to determine the trailer behavior at impact. The analysis showed that the root cause of the damage to landing legs was too much allowable pitch motion of the trailer at impact, forcing the landing leg into contact with the airdrop platform. An additional series of airdrop rigging configurations, consisting of the trailer, platform, energy dissipaters and tie-down straps, were simulated to determine the appropriate set-up to prevent landing leg damage. The configuration selected based on the analysis results proved to be successful in a subsequent field test. The methodology developed for the analysis can be a useful tool for initial analysis of airdrop rigging configurations prior to costly field tests.