er340790, I don't mean to be pedantic, but in the interest of clarification, I assume you mean when TWR gives you the w/v, you then use your method to calculate the crosswind?

Here's one i don't think has been mentioned: i'm ready to be slated by the mathmeticians!!

For Crosswind component ..... Wind Angle + 20 in % = XWC

ie Rwy 26 Wind 300/30 (40+20) = 60% = 18kts

For Headwind Component ...... 110 - Wind Angle in %

ie Rwy 26 Wind 300/30 (110-40) = 70% = 21kts


Seems to work fairly accurately, I also like the clock method and of course the good old graph, especially when winds get a bit close to the limits!

On approach, are you interested in the x-wind or the wind vector which gives you the maximum allowable/demonstrated x-wind for the runway in use?

When on Budgies in the Scottish Isles (and DC10 at bermuda), I used to write a wind table, for each ten degrees, giving this wind vector. That way I knew if I was within the limit.

It was sometimes useful to tell (ask) the controller to give no further wind checks after receiving one within limits.
A wind above the demonstrated limit was acceptable if everything felt right, whereas on other occasions I have gone around when the x-wind was within limits because turbulence made the aircraft almost uncontrollable.

A particular problem with a strong x-wind at 90 (or there about) degrees to the runway can be the along runway component.

Sumburgh 09/27 (15/33 not available at night) is a case in point.

A small change in wind direction can, with a strong northerly, cause the wind to come around the other side of Fitful Head giving an unexpected and sudden tailwind on landing despite the reported wind appearing to be a headwind
There is not much tarmac left if you land (three reds and a white and little or no flare - my technique at Sumburgh at night) with an 18kt tailwind on 09 !!
Cost me several beers to the firecrew in the helicopter club that night!!

sayagaingoaround,

thats the method i always use....its a rough rule but works fine for me! :ok:

You can find both the headwind or tailwind and the crosswind with this formula (a TI-83 calculator will do well with this):

sin(wind_direction-current_heading)*wind_speed = headwind or tailwind component

cos(wind_direction-current_heading)*wind_speed = crosswind

For headwinds and tailwinds, a negative number means a tailwind and naturally a positive number is a headwind.

For crosswinds, a negative number is from the left. A positive number means winds are from the right. Hope this helps!