flying backwards
 

Once flew over killington lake (by the services on m6 in cumbria)
3 times without turning round in a first generation trike.
once at 1500 , once at 1500 blown backwards then once very determindly with the bar between my teeth at about 400 where the wind wasnt as strong but was more "sporting".God the enthusiasm of youth!!!.
Pip Pip.

My information (which is worth exactly what you have paid for it :O ) is that the xwind limit is largely based on rudder authority at the POH final approach speed.

So, if a large runway is available, and you really have to get down, you can fly it 5-10kt faster and "force" the plane down onto the runway, and should get away with it. Not that I would ever try it myself!

Obviously with a 50m wide runway it's easier anyway because you have lots of sideways drift leeway...

There are two schools of thought on how to land; the traditional is to always do a "minimum energy" landing, i.e. you virtually stall at the end of the flare. The other is to fly a bit faster and you have at least the two main wheels down before the stall warner horn goes off. It seems obvious to me that the former technique, while reducing the damage if you hit something (because you are landing slower) will have a much lower xwind limit because you have no elevator authority left and not much rudder authority either.

Not really, although rudder power is clearly a player. Here are a few real world examples - they all exist but for the purpose I'll elect not to name them.

#1 - large span, low wing, moderate lateral and directional stability and moderate rudder power. Crosswind limit is basically set by the need to avoid touching the wingtip on the ground, so the main players are lateral stability and geometry.

#2 - high wing, high rudder power, high directional stability, high lateral stability. We set the limit at about 15kn on that aircraft, although the controls made a 25kn X-wind flyable BUT the sideforces in sideslip were so high that we felt that no normal pilot could reasonably be expected to function in that environment. So, the big player there was directional stability.

#3 - high wing, roll control design that gave very little adverse yaw, moderate lateral and directional stability, very little rudder power (because in normal flight it wasn't needed). So in that case the crosswind limit, which was fairly low, was clearly determined by rudder power.

#4 - biplane, linked roll and yaw controls so no independent rudder control. The aircraft was deliberately landed crabbed right onto the deck (an interesting experience) but the undercarriage was specifically strengthened to take the loads as the aircraft touched down skewed then was pulled straight by it's inertia. So in that case the crosswind limit was determined by maingear strength.

G

N.B. If you've really got a 50m wide runway, land on the diagonal and thus reduce the crosswind component.

Have to admit that I think there's some truth in IO540-C4D5D's theory. That's why I always wheel-landed the Super Cub in moderate crosswinds - it all becomes a bit too uncontrollable at very low speeds just before touchdown if you 3-point it.

Genghis knows far more about these things than me, though. And I'd definitely agree with him that it depends on the type. But regardless of type, you will have more control authority at higher speeds, even if the control authority isn't the limiting factor.

But be careful of that nose-wheel (if you have one) when you land a little faster than usual :ouch:

FFF
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Good on ya Genghis: that was very interesting, and I'm glad to say I think I've learned something today... Cheers!

Andy :D

Super Cub glider towing ops routinely see the pair take off at whatever the wind might be .... with the tug then landing across the strip .. the more adventurous pilots have been seen to land with the wingtip not very far above the grass ....

Sometimes the fibro gable markers have been seen to take a beating ... I am told that it makes quite a "bang" for the occupant(s) ....

I do think that it is a pity to see the generally poor crosswind standard in training these days .....

As an aside, some of the US aircraft with linked controls can be a handful.... I was involved in upping the limit on a Rockwell Commander many years ago .... as I recall the US figure was 15 kt ... we chickened out at a little less than 20 kts as I recall ...