The trade test I had to pass as an engine fitter in the RAF was to carry out valve and ignition timing on a Lancaster's Merlin engine, which then had to start and run correctly! (I did pass before you comment!)
What was your first technical job which filled you with trepidation as it did me?

Sounds like a piece of pish that

Mine, on my 1st day in ASF @ Binbrook was the changing and wire locking of the cabin pressure controller on a Lightning F6 WITH THE SEAT IN

For those who never had the honour of working on the Frightning, the cabin pressure controller is situated behind the instrument panel / rudder peddles

Basically, you enter the cockpit head first and on your back with your feet dangling around the bang seat face blind handles.
You then, somehow have to get head and both your arms in down one side of the centre console and using a selection of mirrors, torches of which the batteries always go piggin flat half way through the job
sockets, spanners (on a piece of string), wire locking pliers and locking wire
That was the easy bit

The really difficult bit was getting out again after the bloke who's job it was to pull you out by your ankles has pished off for a cuppa and a pie

Almost as easy as changing the oil pressure live line from an outboard engine on a Beverley.

My God, you and Tigers makes my first little job on my A40 seem soooooooooo tiny!

I'd have loved to say "I worked on a Merlin or Lightning"!!

Trouble is Lizzie, you have to be OLD to say it!!!