DV,
Thanks for pointing me in the direction of the XV249 Human Factors Report. Personally, I am not convinced that a Nimrod pilot could PROBABLY inadvertantly select AIR ASSIST; although, I admit that the after start checks do not require confirmation the the MIs are SHUT; only that the start selector has been selected to WINDMILL. However, after engine start, there is no reason to have your hands anywhere near the Start Master Switch - the switches next to it are for alternative start procedures. However, as you rightly stated, the judgement of CAM was that it was PROBABLE.
Duncs
