REG NASA-LLIS-0785--2000 Lessons Learned Assembly Acoustic Tests.pdf

1、Best Practices Entry: Best Practice Info:a71 Committee Approval Date: 2000-04-14a71 Center Point of Contact: JPLa71 Submitted by: Wil HarkinsSubject: Assembly Acoustic Tests Practice: Subject selected (large surface area, low mass) assemblies, in addition to the full-up flight system, to acoustic no

2、ise. It is imperative on missions with fixed launch windows that acoustic problems on assemblies not be deferred to system level tests.Abstract: Preferred Practice for Design however, the actual acoustic wave angle of incidence distribution is seldom known. In practice, employing a random-incidence

3、acoustic test envelops the effects of the flight environment.Acoustic noise is usually the most severe dynamic environment for a launch vehicle or payload in the mid to high frequency range ( 50 to 2000 Hz). The acoustic pressure fluctuations will induce severe vibrations in relatively large lightwe

4、ight structures, such as solar panels and reflectors, potentially causing failures of the structure or attached electrical components. These structures should be acoustically tested at the assembly level to avoid potential cost and schedule impacts of a failure during system level testing. The full

5、up spacecraft acoustic test provides verification of the integrated system for the vibroacoustic environment, including verification of the adequacy of assembly random vibration requirements. The acoustic test also qualifies spacecraft elements, such as blankets, cable harnesses, plumbing lines, and

6、 secondary structure not tested at the assembly level.Impact of Non-Practice: The probability of failure during systems acoustic testing, or during flight due to the acoustic environment, is increased.Related Practices: N/AProvided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-Additional Info: Approval Info: a71 Approval Date: 2000-04-14a71 Approval Name: Eric Raynora71 Approval Organization: QSa71 Approval Phone Number: 202-358-4738Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-