Originally Posted by thijsseh

A short lesson in root cause determination:

Start asking 'why':
'Why would the wheels not retract ' is only the first question.
Once you get a reply (for instance 'the locking pin was not removed'), ask:
'Why was the locking pin not removed'
Once you get the answer to that, continue to ask 'why' (like a 2 year old) until there is no need to ask more questions and there is a clear path to prevent recurrence (or to reduce the chance of recurrence).

It is unlikely that you will need to ask 'why' more than 5 times, hence the name '5 whys' for this problem solving technique.

[/ lecturing mode off....]