What is a strong crosswind?

Crosswind landing is a great way of demonstrating that turning by wings (lift effect) is more effective than turning by rudder (slip effect) since you use lift to cancel out not only the crosswind component, but the turning component of the rudder/fuselage as well. The path of the plane will follow the bank, not the rudder.
 
Part of the issue is I instinctively leave the ground with some aileron still held into the wind, normal for a crosswind takeoff.

So, I'm already rolling into a coordinated banked turn into the wind as the plane becomes airborne, rolling out when I guess my crab angle is about right.

As I've said, this may be what masks for me any weathervaning tendency the plane shows in the few seconds after takeoff.
 
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Having had the humbling honor of exceeding the max recommended cross wind component in my RV-8 (minor ground loop :redface:) I can tell you the max cross wind is any wind you or the plane can't handle. :lol:

I was feeling like Bob Hoover and decided that 15knots gusting to 21knots direct cross wind did not apply to me or my plane (Vans says 15MPH max:eek:) so I landed and found out the recommendations do apply to me also. :redface: :dunno:
 
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Geico266 said:
Having had the humbling honor of exceeding the max recommended cross wind component in my RV-8 (minor ground loop :redface:) I can tell you the max cross wind is any wind you or the plane can't handle. :lol:

I was feeling like Bob Hoover and decided that 15knots gusting to 21knots direct cross wind did not apply to me or my plane (Vans says 15MPH max:eek:) so I landed and found out the recommendations do apply to me also. :redface: :dunno:
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Dang! That probably means the laws of physics apply to me too. Shoot! :D
 
I finally got all the pieces together for my Mythbusters episode - model, leaf blower, wife to operate leaf blower and GoPro.

Here's the video:

http://youtu.be/NhCFAJybVyw?list=UUIRbXga4oZn7XAUSLfkBO7w

I half expected it to weathervane into the "wind", settling the matter once and for all and setting me straight.

But I could detect zero tendency to "pivot" into the wind once the pivot was gone. It moved directly downwind, as seems to be my experience in real life with insufficient crosswind technique.

Maybe I'll try it one more time with much larger "tail feathers".
 
MAKG1 said:
I think every poster has missed the point here.

A strong crosswind is one the PIC is uncomfortable with. Period.

Personal minimums are not subject to review by the Internet peanut gallery. They are not determined by the POH (except that they shouldn't exceed limitations). They aren't even determined by a flight instructor except for student pilots.

No PIC should ever feel pressured to raise personal minimums because SGOTI says so. Or even because an instructor or owner says so. The PIC is responsible for the safe conduct of the flight. Full stop.
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This, and nothing else.
 
I was thinking about this further last night, and this video came to mind:

http://youtu.be/b_WmjWAGkLI

Go to about 1:55. Even a 55k nearly direct crosswind does not seem to "weathervane" that third Cub tow plane. The wind gets under the upwind wing and the plane just moves downwind with no weathervaning apparent. Admittedly, the pilot could have been counteracting this yawing moment, but if anything it seems the pilots were all scrambling to come around into the wind as soon as possible, rather than remain in the crosswind and being forced downwind. The Cub in question does not ever come around into the wind until the pilot eventually banks and turns it into the wind.
 
I successfully accomplished a BFR yesterday at Blairsville, GA (KDZJ).

We were using RWY26 with a pretty strong direct right crosswind.

The instructor was a friend, and we had discussed this "weathervaning after takeoff" scenarios, and he was pretty much in the camp that it was a real phenomena.

So we set up these conditions to test it.

- On takeoff roll, use aileron and rudder normally for a crosswind takeoff.

- Leave the plane on the ground for a little longer than normal (50k) and then "pop" it into the air, with feet off the rudders and only enough aileron to hold the wings level.

We did so, and on leaving the ground the plane simply moved laterally downwind (to the left) with zero yawing to the right - or left.

He found it an interesting demo, and said he'd have to rethink things.

As an aside, with it's pusher prop and thrust line very close to the plane's CG, my little Sky Arrow shows practically no left or right turning tendencies on climb, making it a good choice for this experiment.

I really wish I had had my GoPro on. I had taken it with me, but thought it might be a distraction on a Flight Review. Next time we have similar conditions, I will definitely try to get it "on film"!
 
cosine is for the headwind component, sin is for the xwind component.

sin 30 = 0.5
sin 45 = ~.70
sin 60 = ~.86

So, for a 30 deg xwind, the xwind component is 50% (that's the easy one to remember). 45 degrees is 70% and 60 degrees is 85% (close enough).

If you're comfortable coming in faster, a higher approach speed will allow you to land in a stiffer crosswind, too.
 
stratobee said:
I happened to catch my worst crosswind encounter in my old plane on tape by pure chance. It was a pretty sobering experience, but considering it was gusting a flanking 28kts, I think I did pretty well. It starts at 2:28 in when I screw up and get so far blown off course I have to go around. It starts to get real hairy from around 3:25.

https://www.youtube.com/watch?v=7iFx9uaHzQI&list=UUTrG-tHJbJT5lt1lkIXvXNw
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Sorry for the thread drift, but that was a great video. I was compelled to watch the other legs you posted. I was with you 100% until the CTAF call at Cochise, "any traffic, please advise." Ugh :)
 
We had some pretty blustery westerly winds Friday, when I went out to practice for my BFR - which I passed yesterday.

In any case, Copperhill, TN, has a roughly N/S runway, with a line of trees not too far west of it.

Made for about as much turbulence with the wind spilling over them that I'd choose to handle in my Sky Arrow.

Just happened to have my GoPro running:

http://youtu.be/ricgcIz2SHI

Not that the crosswind nearly vanished right before touchdown, and the monkey motion needed to get the finger brakes into play!
 
FastEddieB said:
I successfully accomplished a BFR yesterday at Blairsville, GA (KDZJ).

We were using RWY26 with a pretty strong direct right crosswind.

The instructor was a friend, and we had discussed this "weathervaning after takeoff" scenarios, and he was pretty much in the camp that it was a real phenomena.

So we set up these conditions to test it.

- On takeoff roll, use aileron and rudder normally for a crosswind takeoff.

- Leave the plane on the ground for a little longer than normal (50k) and then "pop" it into the air, with feet off the rudders and only enough aileron to hold the wings level.

We did so, and on leaving the ground the plane simply moved laterally downwind (to the left) with zero yawing to the right - or left.

He found it an interesting demo, and said he'd have to rethink things.

As an aside, with it's pusher prop and thrust line very close to the plane's CG, my little Sky Arrow shows practically no left or right turning tendencies on climb, making it a good choice for this experiment.

I really wish I had had my GoPro on. I had taken it with me, but thought it might be a distraction on a Flight Review. Next time we have similar conditions, I will definitely try to get it "on film"!
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Yep, I'm always surprised how many people, including CFIs, get confused on this; although I guess I shouldn't be surprised considering the 'Treadmill that may no longer be mentioned'.:rolleyes::rofl::rofl::rofl:
 
IMHO, a "strong x-wind" is determined by the one encountering it. But, in technical terms we could probably refer to the maximum x-wind component figure in our poh or afm. That figure is published by the aircraft manufacturer and is based on "average" piloting skills.
 
coma24 said:
cosine is for the headwind component, sin is for the xwind component.

sin 30 = 0.5
sin 45 = ~.70
sin 60 = ~.86

So, for a 30 deg xwind, the xwind component is 50% (that's the easy one to remember). 45 degrees is 70% and 60 degrees is 85% (close enough).

If you're comfortable coming in faster, a higher approach speed will allow you to land in a stiffer crosswind, too.
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Ummm...no...at least not in my plane.

The approach speed is irrelevant. I'll still touchdown at the same speed. And at touchdown (and the last 5' AGL preceding it) is the only time the crosswind component comes into play.
 
timwinters said:
Ummm...no...at least not in my plane.

The approach speed is irrelevant. I'll still touchdown at the same speed. And at touchdown (and the last 5' AGL preceding it) is the only time the crosswind component comes into play.
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Agreed.

I think pilots confuse the recommendation to increase speed for gusts with a steady crosswind.

I do add speed for gusts. But not for crosswinds per sé.
 
There are several speeds and resulting deck angles at which you can land a plane (well, my plane, at least). The higher speed yields means that you get more bang for your buck out of the slip. That translates to less of a bank angle required to counter a given crosswind, or the ability to tackle a stronger crosswind.

Which part don't we agree on....that you can't land at a range of speeds, or that a higher speed doesn't result in a more effective slip?
 
coma24 said:
Which part don't we agree on....that you can't land at a range of speeds, or that a higher speed doesn't result in a more effective slip?
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My 182 lands at only one speed. Well, it should only be landed at one speed. Touching down at a higher speed, before the wing has completely quit, would actually be more dangerous in a crosswind.

I see you are flying a Lancair...and have no idea if the same is true for your bird.

The only thing I've found to be effective in mitigating a bit of crosswind component is to land slightly diagonally when the runway width allows it. Though, this is in a bird that'll land fairly short on any given day. Faster runway lovers probably don't have this option.
 
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