Pyroshock Test Criteria

The purpose of this standard is to provide a consistent methodology for developing pyroshock test criteria for NASA spacecraft, payload, and launch vehicle hardware during the development, qualification (Qual), flight acceptance (FA), and/or protoflight (PF) test phases of the verification process. Various aspects of pyroshock testing are discussed herein, including test environments, methods and facilities, test margins and number of exposures, control tolerances (when applicable), data acquisition and analysis, test tailoring, dynamic analysis, and prediction techniques for pyroshock environments. The most accurate simulation of the flight pyrotechnic environment is obtained for potentially susceptible hardware by testing with flight pyrotechnic devices on actual or closely simulated flight structure. However, high-fidelity flight structure is not usually available early in a program, and this approach does not provide magnitude qualification margin over flight. The alternative approach described in this standard is to perform qualification or protoflight pyroshock simulation tests on potentially susceptible flight or flight-like hardware assemblies as early as possible, then to activate actual pyrotechnic devices on the flight system to improve pyroshock environment predictions and as a final verification. The advantages of this approach are that it may reveal potential hardware deficiencies early in the development program, and it allows the application of a qualification/protoflight margin to assembly-level pyroshock tests. The disadvantages include the potential for incorrect estimates of the pyroshock environment due to limitations of measurement methods and analysis techniques available today and the difficulty in accurately simulating a specified pyroshock environment at the assembly level. Regardless, testing on actual or closely similar flight structures is essential for final system verification.

Document ID 
NASA-STD-7003
Document Date 
Tuesday, May 26, 2015
Related Topics 
Process Control