absolutely must not fail ever I know I'm being pedantic, but no such system exists. The best you can do is reduce the probability of failure to an acceptable l

absolutely must not fail ever I know I'm being pedantic, but no such system exists. The best you can do is reduce the probability of failure to an acceptable limit. Especially since this was a military system, some team, somewhere, estimated the Mean Time To Failure for this system and was satisfied with the answer.