Coping with significant crosswind

[turboplanner]

I dont understand the arguement - you should be flying as you need to, not flying as numbers in your head say you should.Surely a pilot is more concerned about landing safely and holding the craft in the right attitude on descent, for the conditions, than what they think they ought to be doing based on an arbitrary number? The angle and power you need to hold in the crosswind is the main thing - disregard everything else.

 

Either I'm missing the point or this is a storm in a teacup.

 

- boingk

The conversation had moved to how you identify whether the crosswind is in excess of your aircraft's limit, since the wind socks at many airfields are notoriously unreliable guides - see Jabiru Phil's solution.

 

If you are landing with a crosswind within the aircraft's rating, what you are saying is correct; if you are attempting to land above it, (and the numbers are relatively fine), you're likely to go boingk, boingk, boingk.

 

 

[boingk]

Ah, no arguement there at all. Was in a similar situation myself in the flight schools Gazelle which I think I've previously mentioned.

 

Regardless... you *do* need to end up back on the ground at some point.

 

- boingk

 

 

[turboplanner]

Getting back on the ground is like farting.

 

It's how you do it that keeps you out of trouble.

 

 

[facthunter]

True. Sometimes neither is optional, but I thought you used different muscles. Nev

 

 

[Wayne T Mathews]

Uh huh... But sometimes I have to use both sets of muscles at the same time... And that can be a not so pleasant experience. Especially if the wind has lumps in it...

 

 

[David Isaac]

Now this is getting worse ... next we will be talking about explosive gas atmospheres in the cabin ...

 

 

[Wayne T Mathews]

Now this is getting worse ... next we will be talking about explosive gas atmospheres in the cabin ...

Can that happen?

 

 

 

[Guest Howard Hughes]

Can that happen?

Yep, I have experience...

 

 

[eightyknots]

Now this is getting worse ... next we will be talking about explosive gas atmospheres in the cabin ...

The debate is slowly but surely turning to 'greenhouse' gasses......

 

Yep, I have experience...

I take it, HH, that you got more than you bargained for ....or as they frequently say in North America, you got "more bang for your buck"?

 

 

[motzartmerv]

You guys are all talking crap..

 

Hehe

 

 

[kaz3g]

Use the 1:60 ruleMost of you fly final at around 60 knots. If you have to hold 10 degrees into wind to fly the approach you have a 10 knot x-wind

 

Kaz

Tan x = Opp/Adj

 

If Opp = 10 and Adj =60, then tan x = 10/60 = 0.17

 

Artan 0.17 = 10 degrees

 

If opp = 20 and Adj = 60. then tan x = 0.33

 

Artan 0.33 = 20 degrees

 

Not perfectly accurate but closer than I can judge a crab angle.

 

kaz

 

 

[eightyknots]

Tan x = Opp/AdjIf Opp = 10 and Adj =60, then tan x = 10/60 = 0.17

 

Artan 0.17 = 10 degrees

 

If opp = 20 and Adj = 60. then tan x = 0.33

 

Artan 0.33 = 20 degrees

 

Not perfectly accurate but closer than I can judge a crab angle.

 

kaz

Now, try to do this as a mental arithmetic exercise, in flight.

 

 

[kaz3g]

Now, try to do this as a mental arithmetic exercise, in flight

You'd be surprised at the funny things that go on in my head, 80 knots

 

But you can relax because no mental arithmetic is required. Just a reasonable guess about angles... the very same guess you have to apply when calculating the cross-wind component from the message on your friendly AWIS .

 

If you are arriving somewhere and there is no windsock, you can gauge the strength of the cross-wind from the crab angle into wind required to fly your approach. If you need 20 degrees you have approximately 20 knots of cross-wind and are probably in trouble. It's telling you to look for somewhere else to put your bum on the ground.

 

kaz

 

 

[djpacro]

Care to run me through the numbers with an example? Take a significant wind (and a specific airplane type).

 

 

[kaz3g]

Care to run me through the numbers with an example? Take a significant wind (and a specific airplane type).

Hi DJP

 

My first post referred to a fairly typical approach on final at 60 knots.

 

My subsequent post gave two examples of cross winds of 10 and 20 knots respectively.

 

If you are flying a rocket or a slug it requires a lot more work to get an answer but most recreational stuff comes in around the 60 knots figure.

 

It's a rule of thumb that gives a reasonable guide irrespective of whether you are doing 55 knots (Texan 600), 60 knots (Decathlon) or 65 knots (C172) so it covers a fair range of aircraft situations.

 

kaz

 

 

[djpacro]

Edited to eliminate stupidity.

 

The actual limit can simply be the angle of side slip/bank required during the flare for particular conditions (mixed in with pilot competency) rather than a xwind number of kts.

 

In any case, there is a final option of aborting the landing and going somewhere else.

 

 

[facthunter]

The limit is what you can cope with at the flare and after. If your approach airspeed was 60k and the crosswind was the same you would be stationary and at right angles to the approach path. That would be another limit would it not?Nev

 

 

[eightyknots]

The limit is what you can cope with at the flare and after. If your approach airspeed was 60k and the crosswind was the same you would be stationary and at right angles to the approach path. That would be another limit would it not?Nev

Structural Limit perhaps?

 

 

[facthunter]

Yeah that happens after you run off the runway at high speed into a drain. nev

 

 

[djpacro]

Some classic older aeroplanes had crosswind landing gear fitted as an option, I read that it takes the fun out of it.

 

 

[kaz3g]

Depending on the aeroplane, but with types I'd be up in a strong wind in, I a m likely to encounter something like a 30 kt headwind component so my 65 kts is now 35 or so when I need to consider the drift to estimate xwind.The actual limit can simply be the angle of side slip/bank required during the flare for particular conditions (mixed in with pilot competency) rather than a xwind number of kts.

In any case, there is a final option of aborting the landing and going somewhere else.

We are working with airspeeds when we do this, not ground speeds. So, unless you are seriously stalled, you will still be doing around your 65 knots indocated and still be affected by the 30 knots of cross wind so the wind triangle still applies

 

opp/adj = 30/60 = 0.5

 

artan 0.5 = 27 degrees so still holds approximately true

 

I remember Barry Schiff wrote an article published in Australian AOPA a few years back giving several different ways in which the 1 in 60 rule could be used to confound his students... this was one of them.

 

kaz

 

 

[kaz3g]

The limit is what you can cope with at the flare and after. If your approach airspeed was 60k and the crosswind was the same you would be stationary and at right angles to the approach path. That would be another limit would it not?Nev

And a very exciting one, Nev... very exciting!

 

I saw an Auster fly backwards down the gliding strip at Euroa one day but I wasn't that silly even then.

 

kaz

 

 

[djpacro]

Oops, sorry Kaz. I will go back to sleep, forget all this theory and just fly.

 

 

[eightyknots]

Here is a backward flying Piper Super Cub:

 

 

 

[facthunter]

I was doing a shark patrol around Caves beach near Newcastle in the mid 60's and I sat it into wind with a bit of flap out and didn't move forward at all for a while. There was a surf carnival on at the time. They rang up the radio station I was broadcasting on and told us to P8ss off as no-one was watching the surf carnival. They were watching this plane flying backwards.. Nev.