Crow AMSAA Extended Model

[santosh_shetty]

I am looking for comments on implementation of Crow AMSAA extended models. I am currently studying MIL HDBK 189 and found the Crow AMSAA model to be feasible for my work. However, I would like to know the steps involved in the process.
How do you go about developing the test? What is the sample size required?
What happens if the test does not precipitate enough failures?
Additionally, what involvement Management should have in the process?
Are there any good planning tools to go about the process. The project I am working on is a tool that will be utilized in very extreme conditions and hence will be extremely difficult to simulate the test in a lab. This constraint may require us to test the tool in the field. How should failures and CA be developed in this case?

[Pantelis]

You may want to start by looking at http://www.weibull.com/RelGrowthWeb/Crow_Extended.htm

With respect to your other questions, there are tools to compute sample sizes (however all depend on assumptions of the items reliability). I would suggest following the above reference and also asking your good friend "google" :-)

[Lakshmi]

hi,
i am Lakshmi currently doing my masters project on Crow AMSAA Extended Model i have gone thorough all the links that you people have provided in Duane Vs Crow AMSAA discussions.....but unable to finalize what are the parameters that determine the AMSAA model and by using which parameters do we have to plot on log-log graph and what are the expression for lamada and beeta values, expressions for MTBF in Crow AMSAA Extended model...