Wind Direction

[DieselFan]

How does one make the most of wind direction? Eg from the ballooning thread, I can fly at 6000 with a tailwind towards Dbn from Jhb and then over Pmb goto 8000 to keep the tailwind? Is this possible?

I so often hear of people saying we had a headwind, so why don't they go up or down till they get a tailwind?

[Morph]

Yes, when we fly cross countries we try different altitudes to get the lowest headwind/highest tailwind effect. Generally speaking the higher you go the faster the wind, and the wind direction changes as you climb. At low levels ,under 2500ft AGL the wind if affected by the rotation of the earth and the direction bends away from it's normal path by up to 30 deg over land and 15deg over water. This effect is called the Coriolus effect. Additionally the friction caused by mountains, trees etc further influences/reduces the speed of the wind.

It is possible to get a complete change in the direction of the wind between two layers. If you move from one to the other you could experience severe wind shear which is not nice.

If you call the weather office or go to http://www.weathersa.co.za you should be able to give you fairly accurate readings in this regard.

[RV4ker (RIP)]

Am told tailwind does not exist. It aparently a myth

PS
Also some interesting info on the gliding sites. Can make use of mountain waves, but be careful to fly on upwind (leeward?) side and not the other.

What I would like to know is how to read the winds when actually in the air. I came back yesterday and had headwind at FL75, but significant tailwind at FL95? How do you know. Do bases of clouds help?

PPS
Do trikes experience ground effect at low level? In theory I assume would be possible, but just curious. Low wings get more than highwings in bliks.

[Tumbleweed]

Doing my first cross country, we took 1 hour 35 min from Secunda to Springs and 40 minutes to get back.

Beautifull sailing till the last 15 minutes which became such a 'gat stamp' I thought is was part of an initiation shake.

I suppose if tailwind does'nt exsist then the air can move pretty erratically sometimes.