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Old 29th January 2006 | 19:37
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BEagle
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Joined: May 1999
: ATP+Mil
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From: Quite near 'An aerodrome somewhere in England'
IO540, almost - but not quite - complete nonsense.

'Crosswind component' is not considered using max drift; the idea is first to work out the maximum possible drift from the wind considered; that is equal to Wind speed/ (TAS in mi/min). Thus at a TAS of 90kt it would be 2/3 of the wind, at 100kt, it would be 3/5, at 120kt it would be 1/2 and at 150kt it would be 2/5. Fractions being much simpler than decimals in such circumstances.

Work out max drift pre-flight, then analyse the approximate angle between track and wind and use the 'clock factor'. If it's 15 deg off, use 1/4 of max drift, if it's 20 deg off use 1/3, 30 off use 1/2, 45 off use 3/4 and if 60 or more use all of it.

Simple enough - unless unfamiliar with analogue instruments such as wrist watches.

A useful and simple method of heading estimation sadly lost on button-pushing digi-yoof.
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