X wind and drift calculations.
 

I've just posted this in "Flying Instructors" - non instructors are welcome to read and/or answer - but NOT here.

Mental powers only!! No computers, calculators - nothing but brain cells.

Sat at the end of the runway, have been given a take-off clearance which included the latest, up to the second, surface wind report.

How do you calculate if the wind is within X wind limits?

Next question - whilst en-route (or holding at a beacon), you need to calculate the current drift - lets put the aircraft in IMC (so you have no ground features to look at). Remember - no machines (includes radio aids). All you have is wind velocity as given by ATC or the weatherman - and a track required).

Go for it.

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