Originally Posted by
DaveReidUK
Yes, I recall that the Tucanos built by Shorts for the RAF had to be capable of 240 kts.
Apparently RAF single-seat pilots can only navigate when flying at a whole number of nautical miles per minute.
As in a number divisible by 60, you mean (nm per minute)
It was actually the specification's time to height climb (15,000ft in six minutes IIRC) which was the driving force (no pun intended) behind the TPE331 replacing the PT6 in the Tucano - even then it took 6 mins 40 or something like that. NB The JP took over 15 minutes!