SRC Forum - Message Replies

Forum: Reliability & Maintainability Questions and Answers

Topic: Reliability & Maintainability Questions and Answers

Topic Posted by: Reliability & Maintainability Forum (src_forum@alionscience.com )
Organization: System Reliability Center
Date Posted: Mon Aug 31 12:47:36 US/Eastern 1998

Original Message:

Posted by: Robert Webb (rob.webb@uecd.co.uk )
Organization:Ultra Electronics, Greenford, UK
Date posted: Mon Jan 7 6:52:43 US/Eastern 2002
Subject: Reliability testing of rotating electronics
Message:
My company is developing an electronic system to operate within the hub of an aircraft propeller. We are currently drawing up a plan for reliability growth testing and/or accelerated life testing of this system. Can anyone please advise as to whether there are any guidelines for reliability testing of electronics in rotating environments. Best Regards Rob Webb

Reply:

Subject: Reliability Testing Propeller Hub Environment
Reply Posted by: Bruce Dudley (bdudley@alionscience.com )
Organization: Reliability Analysis Center
Date Posted: Wed Jan 9 10:47:16 US/Eastern 2002
Message:
In the military handbook MIL-HDBK-781, Reliability Test Methods, there are environmental profiles for a number of conditions. One of the conditions is the V/STOL aircraft, which has mission profiles that describe thermal test parameters and vibration parameters. While these parameters are not defined as on the rotating hub, the turbo-propeller vibration test spectra are indicated and the levels of vibration and duration are described. I would think that one could convert the vibration values to the rotating hub. Helicopter vibration testing exposures are defined in MIL-STD-810, Test Methods for Environmental Engineering in method 514.5 (Annex A). Acceleration spectral density versus frequency plots are shown for turbine engine vibration exposure.