Using a wind component chart on final

[Piltdown Man]

Just out of interest, how much effort are you putting into flying? Is the aircraft doing what you want? The reason I ask is that if you have been shown the magic numbers to make your life easier. Approaching the end of your downwind leg you select something like, but please don't quote me, 1,700 RPM, one click of flaps and TRIM. The aircraft should be flying itself, nicely decelerating to 65 kts or so. On base leg you should just be there looking at the view working out when to turn finals and possibly even looking for the windsock. Once on finals you will thinking about lowering more flap and reducing to approach speed. At the same time a good squizz outside should tell you if you are drifting to the left or right of the centreline. Correct as necessary. Wait. Correct etc. This is one if those times when less is more.

Best of luck.

PM

[BackPacker]

Here's what I do. As soon as I know what runway is in use, or is likely to be in use, I set that on a cockpit dial somewhere. Most aircraft I fly have at least an ADF and one VOR display, some have an RMI or something else. One of those gets adjusted so that the runway in use is on top.

As soon as I get a wind vector somehow, I can then just superimpose that mentally over the instrument, and I know immediately what sort of wind I'm dealing with.

As others have said, the exact value is not important. It fluctuates anyway. What is important is the direction it's coming from, and the approximate strength, plus any gust factor.

Don't try to overcomplicate things. Especially not when your brain and eyes should be engaged elsewhere.

[Parson]

I wouldn't be able to tell you what heading I had flown in a cross wind VFR approach. Eyes out of the cockpit nearly all the time except for occasional check of ASI.

[OpenCirrus619]

Back to the VOR method - it has the benefit that you don't need to work out angle between wind and heading, you just look.

You can use the DI, ADF or VOR for this - the advantage of the VOR or ADF is that you can do it before you are on Final.



In this example (it's the only diagram I could quickly find):

• Runway heading 35
• Wind direction 040
• Reported wind 30 knots (little high - I know)
• Cross wind component - the blue arrow comes down around 2/3 of the way from centre to outside of the dial. 2/3 of 30 == 20 knots

The full discussion is at: Crosswind Approach & Landing

OC619

[BackPacker]

Originally Posted by OpenCirrus619

Runway heading 35

That should read "runway 35" or "runway heading 350" to make sense.

[OpenCirrus619]

My apologies - comes of trying to post while not letting my manager see I'm not "working".

OC619

[BillieBob]

That should read "runway 35" or "runway heading 350" to make sense

If we're going to be pedantic, runways don't have headings.

[Gertrude the Wombat]

Originally Posted by OpenCirrus619

My apologies - comes of trying to post while not letting my manager see I'm not "working".

Ah, there's a new browser feature we need.


Once Upon A Time one wasted time in the office with Minesweeper, which like all good games at the time had a "boss button" - if you hit Escape the window minimised (on more sophisticated software the game would be replaced by a fake spreadsheet display).


Wot we need is a way for web sites to indicate to browsers whether they're real work or not, and the browser then to react to a boss button if a game (or PPRuNe or whatever) is being displayed.

[Shaggy Sheep Driver]

Piper Classique, post 5, said all you need to know on this. And nothing you don't need to know.

[Frannibal]

Thank you all for your suggestions! I am currently practicing the following "rule of 6" i.e always dividing the wind by 6 then multiplying it with the difference in degrees:
e.g 10 degrees difference = 1
20 = 2
30 = 3 (in this case the crosswind will be half)
etc...

Runway in use: 27
Wind: 250 at 12kts

270-250 = 20 degrees difference
I then take wind speed and divide that by 6 so in this case it is 12/6=2
As there is 20 degrees difference, i do 2 * 2 = 4
The crosswind component is 4.

I have been told that this is a more complicated way of doing it, but it seems to suit me well for some reason! :-s

I understand the DI method, and maybe i can try this out next time i am flying.

Thanks all!

[tmmorris]

That's what I do. It looks more complicated written down than it seems in reality. I'd stick with it.

[dera]

The big question is: Why do you have to know that when you're on final? Does it make any difference? No it doesn't. You fly the approach, and if you can keep it stable, you continue. If the crosswind exceeds your or planes capability, you go around. Simples.

[ddoth]

One should develop a good visual cue of where the runway intercepts the aircrafts windshield to determine if things might be outside your own limits.
However, I always used the approach speed and angle difference on the DG to Rwy direction out of curiosity.

At 60 kts, a difference of 20degrees was roughly a 20 kt crosswind component (1 kt for every degree) .
At 120 kts, the component is half the angle (1 kt for every 2 degrees).
You don't need it exact but good for a rough guide.

Better to not think of it and just do rather than over thinking and getting worked up or worried about it.

[rarelyathome]

Originally Posted by dera

The big question is: Why do you have to know that when you're on final? Does it make any difference? No it doesn't. You fly the approach, and if you can keep it stable, you continue. If the crosswind exceeds your or planes capability, you go around. Simples.

Well it does in some places. For example, our ops manual gives the max demonstrated in the POH as a max crosswind (and please don't start a discussion about max demonstrated v crosswind limit as I'm sure we are all clear). If the crosswind is outside the POH figure, then our procedure is to divert to somewhere where there is a more into wind runway. So it really is necessary to be able to calculate the crosswind both when joining and when on final.

As for continue until the crosswind exceeds your or your aircraft's capabilities, that's a recipe for disaster. It's a bit late to discover your assessment of either's abilities was a bit optimistic as the undercarriage collapses due to a sideways load.

[piperboy84]

This will get you all squared away

https://wordery.com/mental-math-for-...SABEgLPPfD_BwE

https://wordery.com/mental-math-for-pilots-ronald-d-mcelroy-9781560275107?currency=GBP&gtrck=L0hpczdPb3o1R2hxWEZLajd3enJ VMUY1ODZUL05zV1d6SitzcXRCSDhFTjIzeThjbERBV21SNWxlcDBTTGM2aWN ldVQ2RlV3bmczSkE1bkNkUHRVN1E9PQ&gclid=EAIaIQobChMIqLrwjrnS1Q IVljLTCh3EwQwOEAQYASABEgLPPfD_BwE

[dera]

Originally Posted by rarelyathome

Well it does in some places. For example, our ops manual gives the max demonstrated in the POH as a max crosswind (and please don't start a discussion about max demonstrated v crosswind limit as I'm sure we are all clear). If the crosswind is outside the POH figure, then our procedure is to divert to somewhere where there is a more into wind runway. So it really is necessary to be able to calculate the crosswind both when joining and when on final.

As for continue until the crosswind exceeds your or your aircraft's capabilities, that's a recipe for disaster. It's a bit late to discover your assessment of either's abilities was a bit optimistic as the undercarriage collapses due to a sideways load.

You missed the point. You calculate that, on final? That was the key point in my post, on final you don't mess with anything apart from keeping the plane pointing the right direction. If you can't, you go around, it doesn't matter what numbers you came up with earlier.

[Gertrude the Wombat]

Originally Posted by dera

You missed the point. You calculate that, on final?

You calculate crosswind on final and compare with any limits you have to obey, yes. Otherwise you might land (perfectly safely but) outside limits. How else can failing to break any such rules be achieved?


If the crosswind is one knot outside limits I ask for a "wind check" at intervals on final until I get one that's one knot inside limits, then I don't ask any more. Doesn't everyone do that?

[dera]

Originally Posted by Gertrude the Wombat

You calculate crosswind on final and compare with any limits you have to obey, yes. Otherwise you might land (perfectly safely but) outside limits. How else can failing to break any such rules be achieved?


If the crosswind is one knot outside limits I ask for a "wind check" at intervals on final until I get one that's one knot inside limits, then I don't ask any more. Doesn't everyone do that?

But you know that limit before you turn final, don't you? So the actual math has been done.
In our opspecs we are not allowed to start an approach unless weather is inside our tolerances.

[Gertrude the Wombat]

Originally Posted by dera

But you know that limit before you turn final, don't you?

The limit, yes, but not the wind - that's passed with the "cleared to land" by which point I'm almost always on final.

[tmmorris]

Ah, local variations then. I am always given the wind on downwind (and again on final) giving me a bit more time to calculate or at least to raise a couple of eyebrows.