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Winds and runway selection. Which one and how do you know?

Posted: 08 Apr 2018, 18:02
by Jacques
Yep, exactly, it is blowing FROM 040 and towards 220 at 4 kts. Since you always prefer a headwind for takeoff and landing, you would choose runway 04 for takeoff and landing in this situation.

If it was indicating 060 at 10 kts, you would still prefer runway 04.

If it was 190 at 7 kts you would prefer runway 22 (220 degrees).

(apologies...posted over the top of Oracle)

Re: Winds and runway selection. Which one and how do you kno

Posted: 08 Apr 2018, 20:04
by Still Learning
Ok, then, I'll do what the METAR says. (If the winds are 040, RWY 4 it is.) That's easy enough; and to choose the proper RWY that's all I need. Besides, I think you have been very patient with me.
Thank you.

One quick question: Say the winds are 040 but the runways available to you are: 1/19, 8/26 at KLAS, in case you were curious. (Tell me if I'm right.) I would choose RWY 01. Because the difference would only be 30*. If I'm not mistaken, RWY 08 would be showing a 40* difference. Question is: how much would those 10* matter? i.e. (40*-30*) =10*

Still Learning

Re: Winds and runway selection. Which one and how do you kno

Posted: 08 Apr 2018, 20:08
by Oracle427
You must consider the runway length, surface type and condition the noise abatement procedures, current traffic situation and your own proficiency in cross winds before making such a decision.

All things being equal, I'd favor the one more directly aligned with the wind unless I wanted cross wind practice.

Re: Winds and runway selection. Which one and how do you kno

Posted: 08 Apr 2018, 21:04
by Still Learning
Thanks Oracle.

The thing is, there is no Rwy 4 at KLAS. There's a 1, there's a 8 and also a 26 and 19. i only mention KLAS because that's probably where I'm flying to next, in the MD-80.

So, all things being equal, would it make a difference, if I chose 1 or 8?

Thanks.

Still Learning

Re: Winds and runway selection. Which one and how do you kno

Posted: 08 Apr 2018, 21:25
by Oracle427
Don't know the MD-80's requirements at all, so unable to recommend. But assuming the runways both meet requirements and the winds are strong, I'd go for 1 over 8. The difference is not huge.

Re: Winds and runway selection. Which one and how do you kno

Posted: 08 Apr 2018, 22:27
by skelsey
Still Learning wrote:how much would those 10* matter?
I confess I have not read the entire thread so apologies if someone else has already posted this, but in direct answer to your question: it matters about 1/6 more :wink:

The 'rule of sixths' is a quick and fairly accurate way to estimate crosswind component. If the wind direction is 10 degrees off the runway heading, then you take 1/6 of the total wind speed as crosswind. 20 degrees off, 2/6, 30 degrees off 3/6 (ie 1/2) and so on. 60 degrees or more you take all of it as crosswind.

Obviously the reverse is true for head/tailwind component (10 degrees off =5/6 headwind, 20 degrees off 4/6 and so on).

If you are not bumping up against an airframe/ops manual limitation for cross/tailwind then as others have said it is worth checking the charts (usually the general/textual data section) for any preferred runways at the airport in question, plus of course considerations about runway length and surface etc.

Re: Winds and runway selection. Which one and how do you kno

Posted: 09 Apr 2018, 09:29
by Still Learning
(Hopefully) you'll be both pleased and relived when I tell you "I've got it." Or at least I think I do..:)

Someone was asking a question about what wind direction means to the Chief Meteorologist at WGN-TV, (back in 2001.) The part of his reply that resonated with me was when he talked about the north winds that blew into Chicago. And that would make the temps even colder. That made it easy to visualize the winds blowing in from say, Canada.

I understand how you say the winds are blowing from runway 22. And I also understand why it's 040 wind. Kudos to the Chief Meteorologist at WGN-TV. (and to all of you, who have been helping me out for 3 pages.)

As I understand it, if you are standing on the numbers, at RWY 4, and the wind is blowing in your face, the direction you're facing names the wind. In this case would be, 040*

Did I miss anything?

Still Learning

Re: Winds and runway selection. Which one and how do you kno

Posted: 09 Apr 2018, 09:49
by Oracle427
I believe you've got it

Re: Winds and runway selection. Which one and how do you kno

Posted: 09 Apr 2018, 10:27
by Still Learning
Thanks guys, I appreciate the help.

Still Learning

Re: Winds and runway selection. Which one and how do you kno

Posted: 09 Apr 2018, 14:25
by Piper_EEWL
No worries! Glad we could be of help!

Happy flying