Originally Posted by
OldLurker
I suspect it's good old "not invented here", like insisting on using inHg instead of those cissy cheese-eating hPa.
Don't remind me OL. HP had to call for power to the engineer on approach in a Hastings. No problem, you soon got used to "-2, -4, -6, -4", and back to the first number you thought of. Then some suit decided that all UK mil boost gauges be changed from lbs to "Hg. Now you had to convert what you wanted, eg -4, double it, take the result away from 32, and then call for 24, etc. Nice steady 3 degree slopes suddenly turned into diverging sinusoidal excursions until we all learnt the new numbers by heart. Great for STANAG though!