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Is it just my imagination, or is it a fact that many large airliners actually touch down "crabbed" on difficult crosswind landings?

Here's what I mean in this video, or as shown in this picture:

enter image description here

Is the main landing gear specifically designed to allow this? Is it recommended or discouraged by the manufacturer?

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  • $\begingroup$ Related question about landing techniques & crab-vs-no-crab $\endgroup$
    – voretaq7
    Commented Jan 23, 2014 at 23:17
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    $\begingroup$ I enjoy watching crosswind landings way more than a reasonable human being should. $\endgroup$
    – Cameron MacFarland
    Commented Jan 28, 2014 at 5:46
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    $\begingroup$ As I remember from initial ground school for the 747-100 and -200 in 1990, the recommendation was to simply touch down in a crab. In actual practice we typically used a combination of slipping and a crab at touchdown, how much of each depended on the pilot. In all but the heaviest xwinds you could take out the crab. I forget the max amount of wing down you could go, but I seem to remember that 5 degrees of wing down was fine, and that would get a lot of slip. $\endgroup$
    – Terry
    Commented Feb 12, 2015 at 6:06
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    $\begingroup$ @copper.hat It's a matter of timing, and it comes with a little practice. It's better to err on the side of not getting it straightened out before touchdown as all that means is you're touching down in a crab. If you get it straightened out too soon, the xwind will drift you sideways with respect to the runway. If that happens, put the crab back in and, possibly, more bank. It's not all that hard to time it well in a 747 or any aircraft that you're getting altitude calls from the radar altimeter or another crew member.. $\endgroup$
    – Terry
    Commented Feb 12, 2015 at 7:49
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    $\begingroup$ @CameronMacFarland agreed, they are my "kitty videos" as well; well those and Russian Car Crash vids. :D $\endgroup$
    – CGCampbell
    Commented Feb 12, 2015 at 13:40

1 Answer 1

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The landing gear is indeed designed to cope with crabbed crosswind landings.

The recommendation is to avoid crab on landing however in severe crosswind conditions it is sometimes impossible to decrab completely without introducing excessive bank. Therefore some residual crab has to be allowed.

Airbus recommends less then 5 degrees of residual crab on landing, but aircraft are designed to cope with more.

An exceptional design is found in the B-52, where the main landing gear can rotated to be aligned with the direction of travel to deal with extreme crab angles.

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  • $\begingroup$ Nice. The 747 in the picture above confirms that it can be a lot more than 5 degrees :-) $\endgroup$
    – Philippe Leybaert
    Commented Jan 23, 2014 at 22:34
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    $\begingroup$ That's an All Nippon 747, as a Japanese Airline, they're into their drifting. $\endgroup$
    – Jon Story
    Commented Dec 19, 2014 at 10:48
  • $\begingroup$ I was going to mention the B-52's rotating gear; good catch there. I wonder if any other designs have incorporated it. I know the 747's mains will rotate counter to the nosewheel to assist in taxiing on the ground, but if you were applying rudder to straighten out of a crabbed approach at touchdown, that system if active would point the wheels into the wind instead of down the runway. $\endgroup$
    – KeithS
    Commented Jun 24, 2015 at 19:05
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    $\begingroup$ @PhilippeLeybaert this is not obvious. The aircraft may be going to the left of the runway, the angle of view may emphasize some angle and reduce other, and lots of more perception biais may exist. $\endgroup$
    – Manu H
    Commented Mar 14, 2016 at 11:03
  • $\begingroup$ All Airbus aircraft have high clearance below the engines, so they can afford recommending lot of slip. Especially B737 has low clearance, so crabbing is recommended for it. $\endgroup$
    – Jan Hudec
    Commented Jul 4, 2016 at 17:54

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