Another one for working out time taken when doing diversions...
GS - 140kts per hour so:
140/60, take it down to basic fractions - 7/3.
35nm leg, divide the top number into the distance to fly (7 into 35 = 5 then times it by the bottom number 3 * 5 = 15 mins). Its easy once you have some yardsticks stored in your head if your not good at working the fractions out...once you realise estimates are good enough then you end up just using simple rules like 120 = 2 miles a minute, if your slightly over or under then it doesnt matter much, the estimate will still be good enough, just use common sense and add/subtract a minute if necessary. 90kts is 1.5 miles a min or 3/2 in fractions, 100kts - 5/3.
Last edited by wbryce; 22nd March 2008 at 21:31.