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Believe B-52s have steerable main gear for landing crabbed.

EGLM & EGTN

Touched down fully crabbed and held it….

Home runway, in central Ontario, Canada, Canada

Why?

France

How does @Pilot_DAR s photo indicate that the plane was “touched down fully crabbed”? It looks to have been landed in a slip, one which kept side loads off the landing gear despite a very strong crosswind.

I don’t land in strong cross winds all that often, but my preference when doing so is to move from crab to slip at a height well above that where any lack of smoothness can be worked out before I hit the ground. The only plane I’d fly to the ground in a crab is an Ercoupe, which has a remarkably overbuilt landing gear designed for that job – the aircraft has no rudder pedals. I know airliners are also designed for that technique, but I’m not planning on flying an airliner soon.

Last Edited by Silvaire at 29 Sep 21:41

Handling practice.

On the ice, scrubbing tires isn’t a thing, and there’s no runway to drift off, so I can practice… There was not a significant crosswind that day, I was mostly into the wind (I could choose the runway direction), and tracking a more or less straight line, though heading and track were considerably different. No problem with roll control, until I slowed, and could no longer hold the wing up.

When landing on unbroken snow (wheels or skis), or on sand, I like to “test” the surface first, so I put one wheel down first at flying speed to feel the drag on the wheel. If the wheel drags, or I otherwise don’t like the feel of the surface, I lift it out, and do not land. If I’m content, I’ll roll at least my “runway” length, lift off again, and go back around to check my wheel mark. If it’s okay, I’ll repeat on both wheels, and see if the results are similarly pleasing. If so, I have a runway, if not, I do not allow to the plane to slow below liftoff speed. When landing on floats in a crosswind, it may be desirable to put the upwind float into the water first, and allow the downwind float to settle in as roll control reduces with speed.

Though I won’t land wheels into snow I suspect more than a few inches deep, on skis it can be pretty important to assure that it’s not too deep to get back out. Obviously, it’s wise to not be crabbed much touching down on skis, but I’ll still try to put only one down, holding the other wheel off, to assess the surface. I like to be confident about precise roll and directional control on the surface, So, I practice….

Home runway, in central Ontario, Canada, Canada

But why land crabbed instead of decrabbing just before the wheels touch and having the airctaft lined up with the runway heading, instead of putting sideways strain on the landing gear?

France

Why not, he’s on ice so there wont be much side load at all.

One thing I don’t quite understand is that the image looks as if you’ve got one wing low, whilst I thought landing crabbed would be wings level with the fuselage pointing in a different direction to the track over the ground

gallois wrote:

But why land crabbed instead of decrabbing just before the wheels touch and having the airctaft lined up with the runway heading, instead of putting sideways strain on the landing gear?

Certainly on a friction surface, I would minimize sideload on landing gear. On ice, it’s not a factor, which was why I was practicing that day. It was all about control, what could I make the plane do, both into the wind and crosswind. Yes, it is certainly possible to land wing low without being fully crabbed, and to land in an intense crosswind without lowering a wing much, I just like to practice when conditions invite. A frictionless runway which is ten miles in all directions is too inviting to resist!

Home runway, in central Ontario, Canada, Canada

There’s possibly no reason why not on ice. As I wrote I have never landed on an ice lake or similar.
Crabbing is used to stay on a normal approach with the nose into the wind and on the centre line and wings level. The same as you would do in a flight from A to B with the wind coming from the left or right whilst maintaining the magenta or green line.
So if the wind is coming from the right your heading is to the right of the runway but the nose stays on the centre line.
Just before touch down, usually in the flare you turn the aircraft to line up with the centre line by pushing the left pedal as you would do in a soap box cart. However, if you did nothing else a strong wind might well lift the into wind wing or push the aircraft left. So you add into wind aileron at the same time as pushing the pedal. How much depends on the aircraft. But as the aircraft slows along the runway and depending on type of aircraft you may need to add more into wind aileron to stop the aircraft from turning.
In a Robin 300/400 for instance on take off and landing in a cross wind you can just about use full aileron from applying power to wheels leaving the tarmac and the reverse when landing, to keep you straight during landing and take off roll. In a Seneca or Seminole you need to reduce the amount of into wind aileron as you speed up during take off and add it whilst slowing down during landing.
It seems the technique is not widely used in GA outside France but it was a method I was taught and I find it works for me. I have tried coming down the centre line on short final with into wind wing tilted towards the wind and keeping aligned with the centre line using rudder and keeping that configuration until touching down wing low and on one wheel. I decided that the crab technique suited me better.

France

gallois wrote:

It seems the technique is not widely used in GA outside France but it was a method I was taught and I find it works for me.

I was taught the same technique in Sweden, in 1984.

ESKC (Uppsala/Sundbro), Sweden
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