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wrathchild666
4th May 2007, 22:26
Whilst using a best guess for wind correction hasn't let me down as yet. I would appreciate some help with something i feel my former instructors didn't take enough time over.
I understand there is what is known as the 'clock method' of wind correction. I have a little understanding of what is involved, but a comprehensive explanation from anyone would be massively appreciated. (preferably in Disney format as i'm a bit thick).:}

Cheers

foxmoth
5th May 2007, 07:21
Work out MAX drift ( windspeed divided by IAS x 60). take the wind direction and heading - look at the angular difference and apply it to a clock face. the amount round the clock is the amount of max drift.
i.e. 100kt a/c with 20 kt wind - max drift = 12 degrees, wind angle 45 degrees (3/4 round the clock) drift = 8 degrees (3/4 of 12). You can also use this for crosswind component - in this case, 20kts of wind so crosswind component = 15 kts.
For head/tailwind component take the wind angle away from 90 then apply to the clock face, so with a wind at 50 degrees off the nose or tail, subtract from 90 = 40 degrees = 2/3 round the clock = 14kts (round up or down to make things easy, so use 21 kts instead of 20 making it easy to find 2/3).:D

Sleeve Wing
5th May 2007, 19:15
Quote -Work out MAX drift ( windspeed divided by IAS x 60). - unquote.

Nearly right, foxie, me ol' mate ------

MAX. DRIFT = (Windspeed/TAS) x 60. :ok:

Sleeve.

foxmoth
5th May 2007, 19:30
OK I will give you that, I was dashing out before writing this - but most light aircraft are not flying at heights where there is a significant difference and in that event I would not bother working that difference out anyway and just use IAS.

skyhigher
6th May 2007, 08:02
wrathchild666,

pm me your email and i will send you a document i wrote detailing clock method etc...

cheers...

wrathchild666
8th May 2007, 17:39
Cheers guys, that's a great help!:)

jamestkirk
10th May 2007, 12:11
Just to clarify.

Are you talking about drift/time calc. whilst in flight for x-co purposes.

Or, to actually work out the wind speed/direcition in flight.

If its the latter, no idea.

If you would like something i produced on fan lines, cross track error, standard closing angle and time calculations, then please PM your e-mail address to me and i will forward the word doc.