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: Edmund
Date posted: Wed Aug 20 7:55:12 US/Eastern 2003
Subject: Failure Definition & Scoring Criteria (FDSC)
Message:
My project is proceeding into Reliability Demonstration phase so there is a need to develop the FDSC document for failure sentencing. Is there a Military Standard for developing FDSC. The contractor recommended to follow the M1E1 tank FDSC which says that Mission Reliability Factor (MRF)= Failure Criticality Number x Probability of mission to be chosen. There are 2 sets of requirements in my project namely Mission Abort (MA)and Mission Affecting Failures (MAF) to be fufiled. The MRF will not always results in 1 chargeable failure depending on the mission probability and failure criticality. I would like to query is this the acceptable approach to develop FDSC in the military? If not how do i charge MRF=1 for every chargeable failure? Please advise! Thanks alot

Reply:

Subject: Reliability definitions
Reply Posted by: bwd (bdudley@alionscience.com )
Organization: RAC
Date Posted: Tue Nov 4 13:24:45 US/Eastern 2003
Message:
The old military standard MIL_STD-781D has a section on failure categories. These categories define relavant, non-relevant and chargeable and non-chargeable failures. You can look up this standard in the obsolute specification lists on the web.