INVESTIGATION OF PREDICTION METHODS FOR THE LOADS AND STRESSES OF APOLLO TYPE SPACECRAFT PARACHUTES VOLUME Ⅱ – STRESSES

摘要

The major factors in structural analysis of parachutes are re-viewed, Including ultimate strength, design factors, safety factors, external loading, and internal loading of the individual structural members. A method for computing the internal load distribution for a parachute with a given applied riser load and canopy differential pressure distribution is presented, and comparisons of the predicted canopy shapes and internal loadings with Apollo development test results are given. The analysis discussed above is modified to give better representation of ribbon parachutes with vertical ribbons, and a comparison of results of the two analyses is given. A study of data obtained in dynamic loading tests of pilot chute risers adds to the under¬standing of the effects of high load onset rates which occur at main parachute canopy stretch. A study of methods for measuring parachute aerodynamic and internal loading is performed, and a plan is developed for a three-phase test program to acquire needed data.