The Pilot/Amateur A&P Mechanic who, ironically enough, carries a bunch of tools with him and attempts to troubleshoot/fix everything and anything that breaks.

Particularly annoying as PF, as this rare breed of tool pulls and resets circuit breakers at random causing numerous other items to suddenly shutoff/reset.

Further easily identified as the guy who hovers over the mechanic, often in said mechanic's way, while delivering a lengthy dissertation on why it broke, how it broke, the many different times they have seen the item break, possible causes of the failure, and finally how to fix the failure.
(It's funny watching the mechanics sit and nod, you can almost read the writing on their faces)