JF - many thanks for your sage words!
I am currently involved in a little discussionette with a certain aeroplane manufacturer regarding manual override for certain safety critical systems controls which they consider are not needed - software will be sufficient. Hoorah....
Really?
An ex-Harrier TP chum (Airbedane) has given me an insight into his view of the dangers of relying upon s/w after it nearly killed him - and the particular s/w I'm discussing has never been specified to be flight critical... Thus my old-fashioned and slightly jaundiced aircrew view that s/w will f**k up and I want my aircrew chums to survive that incident is reinforced by very high-priced TP opinion!
Just see the recent Virgin Atlantic expereince with the A340-600 fuel system computerised madness to see what I mean. For ex-Hunter mates, it's like having the bingo lights monitored by the fuel gauges - so if they gauge says there's plenty and the bingo sensors say there isn't, then the bingo lights are overridden.....
Until it goes quiet, that is...... Then on comes the "Oh Bugger" caption.