I believe many people here have seen at least one of Cargospotter's videos of crosswind landings at Düsseldorf (DUS/EDDL). There are several of them. I picked this one:

Crosswind landing

I think the pilots land their aircraft manually in case of such heavy crosswinds. But is that true? Or do they lean back and watch the scene as the autolanding system does its job?

This somehow related question suggests the plane is operated manually.

Are there any regulations as to when using autolanding and when to do it manually? I know this might be opinion-based, but could autoland even handle these crosswind situations?

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    $\begingroup$ One reason why autoland systems haven't been developed with high crosswind capability is that autoland is needed most for low-visibility conditions, which usually coincide with calm or light winds. $\endgroup$ – pericynthion Jan 30 '17 at 21:44
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    $\begingroup$ @pericynthion Or with conditions in which landing isn't safe anyway, such as a strong thunderstorm. $\endgroup$ – reirab Jan 30 '17 at 22:07
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    $\begingroup$ It's not opinion based. The limits will be specified for each aircraft type and autopilot system installed. The company may also restrict this further. Rather than have a specific regulations it will defer to the type certification and manufacturers limits $\endgroup$ – TomMcW Jan 31 '17 at 18:20

The B777 is limited to a max crosswind component of 25 knots when using Autoland so it is most likely that it was a manual landing in the photo above.

The B777 has a "max demonstrated crosswind component" of 38 knots. Some companies will round this up to 40 knots for a company limit.

The "max demonstrated crosswind component" is not a limit. It just means the aircraft can land with that wind speed, in a crabbed configuration, without damage to the aircraft or landing gear.

Crosswind landings for certification are done in a crabbed configuration. Boeing has demonstrated landings for the B777 with a 38 knot crosswind, so that becomes the Demonstrated Crosswind Component.

If Boeing had tested with winds greater than 38 knots, AND it resulted in damage, then the B777 would have a 38 knot Crosswind LIMIT.

Of course there was no damage at 38 knots and there is nothing preventing pilots from landing with crosswind components greater than 38 knots.

Since Boeing has not tested or demonstrated crabbed landings ABOVE 38 knots, we don’t know what the actual limit is when damage may occur due to side loading.

So when landing with a crosswind greater than 38 knots, it would be prudent to use a technique that would involve a slip and removal of any crab at touchdown so that excessive side loading is avoided.

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  • $\begingroup$ May I ask if I understood this correctly: up to 25 knots the B777 pilots can use autoland, up to 38 knots they can/must land manually and above 38 knots they cannot land and must either wait or go elsewhere, right? $\endgroup$ – PerlDuck Jan 31 '17 at 19:51
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    $\begingroup$ 38 knots is really just a recommendation, not a limit. Above 38 knots the pilot must remove the crab at the moment of touchdown, or use side slip. $\endgroup$ – Mike Sowsun Feb 1 '17 at 0:02
  • $\begingroup$ But you better be very experienced with crosswind Landing technique and current as well. Big gamble with 300+ lives aboard to casually do otherwise. $\endgroup$ – Carlo Felicione Dec 2 '18 at 17:03
  • $\begingroup$ @MikeSowsun So, for the sake of argument, suppose a pilot does decide to land at higher speeds than 38 knot, how does the company later check whether or not damage indeed happened. $\endgroup$ – curious_cat Dec 2 '18 at 17:08
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    $\begingroup$ "Maximum demonstrated crosswind component" just means that's the highest they showed during certification testing; it doesn't mean that's the limit of what the plane can do safely. But 38kts is already quite high; they probably couldn't find any higher crosswinds during testing--outside of a tornado or hurricane, at least. $\endgroup$ – StephenS Dec 2 '18 at 17:19

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