scope:

Abstract:

During the unit level vibration testing of the BEO of the LIDAR instrument of CALIPSO Satellite, the composite structure spider legs supporting the BEO secondary mirrors failed catastrophically. After the initial analysis of the BEO, several small design changes to the structure were made, each of which was so minor, with so little impact on the overall design margin, that the structural analysis was not updated. However, the combined effects of these modifications consumed all design margin, leading to failure during qualification testing.