A Technique for the Calculation of the Opening-Shock Forces for Several Types of Solid Cloth Parachutes

摘要

In 1965, the Naval Ordnance Laboratory was engaged in a project which required the deployment of a 35-foot-diameter extended-skirt parachute (type T-10) as the second stage of a retardation system at an altitude of 100,000 feet. At that time, there were no available data on the T-10 parachute deployed under similar circumstances. This new parachute opening-shock calculation technique was generated as a solution to this dilemma. A drag area ratio-time ratio signature derived fro infinite mass wind-tunnel parachute deployments is combined with Newton's second law of motion to develop instantaneous velocity ratios and shock factors during the deployment process. Methods of computing the reference time (to) and the inflation time (tf) are presented. (Author)