I'm kinda' curious myself;
Been a Boeing man for 20 years ( though not at all exclusively ) and I've never heard the term either. I know of various, specific, spanner-type tools for various parts of Boeing iron but no "Beoing spanner".
Could be we're talking the same language...except we're talking a different language
In other words, it's just a matter of regional terminology.
Some translated "Britishisms" I've had the pleasure of making the aquaintance of:
Spanner = Wrench
Nut runner = Ratchet
Bits = Parts
Gudgeon pin = Piston pin ( or wrist pin )
Snags = write-ups ( logbook )