Safety Margins Established by Combined Environmental Tests Increase Atlas Missile Component Reliability

A reliability test program known as a ``Search for Critical Weaknesses´´ has been put into operation by the Convair-Astronautics Reliability Organization. The function of this program is to detect critical component weaknesses so that corrective action can be taken before operational failure occurs. Components selected for testing are subjected to combined environmental severlties at and beyond the design requirements. This is done in order to establish a margin of safety and to be able to reassess component reliability in the event that actual flight environments differ from those expected. After completing the first three phases of this program, 203 component types, consisting of 980 individual specimens have been evaluated. A fourth phase in which 105 component types are being tested is nearing completion and a fifth phase has been initiated. This paper covers the testing procedures and the techniques used in determining the relative component reliability during the first three phases of the testing program. In addition, an explanation of representative components´ weaknesses was revealed during the tests, and the corrective action taken has been included.