Working out the crosswind component

[hugh flung_dung]

Why make something complicated when it can be staggeringly simple - no sums are needed.

1. When on final look at your DI/HSI and find the reported wind direction round the outside of it.
2. Mentally drop a line from the wind direction until it hits the horizontal centre line.
3. The proportion of the centre line between this intersection and the centre is the proportion of the reported wind that's across the runway.

(As originally described a bit earlier by low n' slow)

If you do the same thing horizontally you get the headwind.

This is as accurate as you want to make it and takes about 2 seconds.

HFD

(BTW, if you want to know what the components are before you reach final just turn another compass rose (RBI/CDI?) to the runway track and use that)