I really hope that Gertrude is engaged in a bit of good natured trolling here!

But he is highlighting a major issue I have with the way many pilots think about wind. The right time to think about wind is the pre-landing checks *primarily*. I certainly include consideration in mine, but most checklists don't. That is the time for any deep thinking on the topic, as minor variations as you trundle down final, whilst they can make a difference, happen more rapidly than you are likely to get updates on RT. Plus the instrument the tower are using to determine wind is not (usually) adjacent to your touchdown point.

The reason to throw an approach away from final is that the picture from the cockpit is all going wrong - not any last minute arithmetic. Any pilot who is adequately ahead of the aeroplane should either be comfortable they are well within limits, have already made a decision to go-around, switch runway or divert, or be aware that they are close to personal limits and prepared for the high workload and possible late decision based upon the view out of the window to go around. But they should have all of that sorted in their minds before they turn final - and I'd argue most times before they turn base.

G

Maybe this chap has his CRP-5 and a marker pen out during his CRAP checks :eek:

I've just done a quick route plan on Runway HD based on Perth 21 runway at 60 knots. Current wind is 250/15. Magnetic track is 222deg. Which would amount to a crab angle of 12 deg.
This app uses true track converted to magnetic heading so is 3deg incorrect.
All that is required is the runway magnetic track converted to current wind corrected mag heading at landing speed. This would be done well before final.
Alternatively. Know in advance what the pilot's or aircraft's max crab angle is and watch the compass/DI on final for excessive difference to runway heading, and go somewhere else as required.
Faffing about with mental arithmetic and charts on final is nonsense.
I've forgotten whether runways are in magnetic or true, or is that wind directions?

Standing by to be corrected but:

Runways are magnetic (well, in most parts of them world).

Winds given by ATC or on an ATIS are magnetic, met winds (as seen in TAF/METARS) are True....

Do agree with your comment about faffing about with charts on finals...

I'd argue that knowing the expected wind, plus the breakdown in headwind and crosswind, is one of the most important pieces of information required in the planning phase of the flight. If the crosswind is outside club/aircraft/personal limits, then it doesn't even make sense to show up for the flight. If it's close to limits, you may need to consider passenger comfort or maybe replanning the flight to a more suitable airfield.

The wind that you get through METARs, VOLMET, ATIS, from ATC, or whatever, is merely confirmation of something you should know already. And a chance to detect any deviations.

Also if 3 degrees makes any appreciable difference to whether you're within wind limits or not, then frankly you shouldn't be flying !

Admittedly there are countries where the magnetic-true variation is massively more than 3 degrees, but none of them are in Northern Europe this year.

G

What is a CRAP check?

I'm guessing Carb Heat, geaR, Airspeed, Propeller Pitch?

G

Final landing check:

Carb heat in correct position
Runway clear (and cleared to land)
Approach satisfactory
Propeller fine

:8

ahhhh, he says, nodding knowingly.

G

I never realised working out the crosswind component was so complicated!

The wind might technically be within "limits" but you might get on the approach and have doubts about whether it is safe to land so act accordingly!

CRAP checks? I don't know how I've managed without these "painting my numbers" mnemonics for years.

The worrying part here is that you make decisions based on ATIS/AWOS/tower given wind.

This thread scares me.

The closest isogonic line is 10.5E here :)

Agree 100% with your comments though. No-one should do continue/go-around decisions based on silly xwind calculations, which are nowhere nearly accurate anyway, when on final. If it looks good, continue. If it looks like it won't work, go around.

And you take those numbers as the actual wind? That is scary. I really hope you are trolling.

Forget the bull**** and fly the aircraft.

I'll freely admit light aircraft stuff isn't my aisle, so maybe you guys do things differently but that comment has made me curious.

Are you really saying you wouldn't make a certain decision :8 if say, tower reported wind is significantly outside your and/or your aircraft's crosswind limit ....

Thirty years in control towers and not once did I have an aircraft go around due to a reported crosswind. They all continued and made their own decision based on the aircraft's handling, usually very short final.

Ok thanks for that, so it's a case of "if it looks/feels alright" it is regarded as acceptable to press on and land, regardless of what the tower reports ( and is perhaps on the tapes..?

And equally so, it is acceptable to initiate a go-around, even if the tower says it's well within limits.

The pilot is the commander of his aircraft, and responsible for both good and bad decisions. The tower is only responsible for passing information and in some cases, giving permission or instructing a go-around because of external factors. No controller anywhere in the civilian world has however any say in whether a particular approach is safe or not from the perspective of aircraft handling and performance. That decision is absolutely and completely ALWAYS with the pilot.

G

Let's not forget that the original post is from a student pilot.
Students are trained to fly with an accuracy of a few minutes of arc, or at least try to.
Picking the wrong answer in the Nav written exam may be one degree different to the right answer, but will fail the question. So the question is understandable.

I'm perhaps a little more concerned about some of the questions and views being expressed by apparently experienced pilots. I'm pretty certain that Gertrude has his tongue firmly in his cheek, but others perhaps not.

G

Just to be clear GE I wasn't implying that was the case....bottom line is it is the commander's decision but I was simply very interested in the comment about ignoring reported winds.

I'll get back in my taped/FQISd/ FDRd/CVRd monitored box now...

Ignore - no.

Take a rational command decision, using more information than just that - yes.

G

I can't speak for the others, but I'm saying that my decision to divert, go around or whatnot, is not made on final, based on the ATC reported wind. It will be decided much earlier on, perhaps even before starting the flight.

Because of that, I essentially ignore what the tower reports as the current wind (as part of the landing clearance). By then that information has become largely irrelevant, because I have already made the decision that the wind is within limits, so I'm going to see, and deal with, whatever wind comes my way. And a go-around decision will not be based on absolute crosswind values, but on whether I feel confident I can pull off a safe landing.

The only thing I do when the tower reports the wind on final, is a gross error check to see if it's still more or less the same as what I've heard earlier. I've been in a weird windshear situation where the wind that I had at 1000 feet on downwind, was 180 degrees out from the reported surface wind. That took a bit of mental gymnastics to decide what I was going to do. (And the approach was, well, interesting...)

Quite right Gengis.
So the question "is it acceptable to use a chart on final?"
No, fly the aircraft.
To a student, what picture looks "right" or wrong if he hasn't been there before?
So he goes by numbers.
What's the easiest way to get numbers?
A pax once, on final to 06 with Anstruther due south looked out the windscreen and said " is that Anstruther over there?"
"Yes, please excuse me while I calculate our crosswind component".

it has always been strange to me that a controlling service of whatever nature would not actually give the cross wind component rather than the wind speed / direction. With modern day tools this could be automatically calculated and be no more radio traffic. It would stop all of this phaffing with calculation / rules of thumb etc etc..

RAF sometimes do it when it's strong - e.g. 'wind 240/24, 20 from the right'. Not sure what the threshold is for doing that.

"Because of that, I essentially ignore what the tower reports as the current wind (as part of the landing clearance). By then that information has become largely irrelevant, because I have already made the decision that the wind is within limits, "

I wish I did my landings at places where the wind never changed suddenly and unexpectedly.

Well, I can imagine Scotland has some worse winds than Rotterdam, but still, I'm right inside the aircraft that's being tossed around by the wind, so I experience everything first hand. While the controller is in his comfy tower and needs to read the wind from a scope. Which is fed by a measuring device that it some distance away from both him and me.

Which of the two is going to give me the best information, to make a split-second decision whether to go around or not?

It's not a split second decision, you're not listening to the controller and doing mental arithmetic when you're so near the ground that a split second matters!


However when you're being tossed around at a few hundred feet it can be encouraging when the controller tells you that it's a lot better lower down. (You'll make your own mind up whether you believe him when you get down there, of course.)

As you elude earlier on CV, I was taught the same simple rule as you.

Crosswind of 30 degrees off the runway heading, apply half the wind speed and 60 degrees off, apply the full wind speed. Pro-rata anything else based on that.

Maybe we went to the same place :ok:

The clock code is pretty universal.

Up to 15 degrees off the runway - quarter way around the clock, a quarter of the wind is crosswind.

Up to 30 degrees - half

Up to 45 degrees three quarters

Up to 60 degrees, or over 60 degrees, treat all the wind as crosswind.


As for CV's airbus. - well either the Captain was equally incompetent, or was a complete @rse making an extremely expensive point to his f/o. You can use the same clock code to estimate tailwind. Within 15 degrees of the runway heading count a quarter of the total wind as tailwind, and so on.

Check with a calculator and this is as accurate as you need for most purposes.

Of course maybe the Airbus f/o was struggling to get the numbers into the FMS and determine landing distance? That sounds perhaps a bit more likely.

G