Working as a junior Engineer at a small firm in Somerset called Westland Helicopters. Realised that all the most interesting Engineering jobs went to people who knew about flying, and I'd better learn. Later discovered that flying was fun for a whole bunch of reasons unrelated to Engineering.
The fact that Genghis Sr. was an Engineer at Supermarine, and named me after his favourite war hero (an RAF pilot), the story of whose exploits was a compulsory part of my upbringing may also have been significant.
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