RAF Guetersloh, 18(B) Sqn flight planning room circa '74; Sgt crewman being Staneval checked on a LL Navex:
C'man: That's 157 degrees - call it 160, 20.3 miles - call it 20, at 90 knots that's just over 13 mins call it 15.
Staneval C'man: That's a 'C' cat call it 'D' !!!!!!!!!!!!!!!!
Oh happy days on the 'real' 18(B) [Wessex] Sqn