Landing the big ones.

[22tango]

Im currently doing a PPL and the other day was doing crosswinds. Basically im being taught to crab in, then in the flare, straighten with ruder, and opposite alieron. Just wondering if its a similar proceedure in the airliners, ( i think it isn't) or are they less affected by crosswind?? Secondly, is the flare on any landing the same as a light plane, or does it really just fly onto the ground? If any one could give some info that would be great.
cheers

[Mebro]

Ok here is a very very good cross-wind landing technique....

u probably won't understand some of the tings mentioned but unfortunately I won't be able to just expali in words need to be there in other words sorry !!!

* 20'ht Reselect Attitude - Move Impact point Heading Still Offset

* Fly Aircraft to Impact Point - Main Wheels First

* Yaw Aircraft Straight (Eyes Outside)

* Simultaneously Lower Upwind Wheel (Stop Drift - Keep Aircraft Straight With Rudder)

*Place Aircraft on The Ground

Upwind Wheel Touches First Followed By The Other Main Wheel Finally The Nose Wheel

NB: Aircraft Must Be Tracking Straight-Level Attitude...- To Track Straight - Wings Parallel Aircraft in Balance.

Hope this helps .....Have fun ...

Happy Flying
Mebro

[Diesel]

22Tango - Yep much the same. Certainly bigger aeroplanes have their own problems but don't worry about that. The technique you describe is quite normal and works on all aircraft. Four engine aircraft are more restrictive with regard putting the upwind wheel on first due the possibility of scraping the outer engines. However master the technique in your posting and you won't go far wrong. I believe the Tristar was flown cross controlled (rudder and opposite aileron) much earlier but never flew it. Have flown 737/747/757 and 767 - always worked for me.

Good Luck and keep practicing.

[Lazlo]

I fly the 757/767 and yes it is pretty much the same. Crab in and in the flare squeeze off the crab with a bit of rudder. Maybe use a bit of into wind aileron but need to be very very careful due to the engine pod clearance. The other option that I have seen a lot it to just land it with the crab on since the gear is stressed to handle some pretty serious crab angles. That's what autoland will do as it uses up to a max of 2 degrees bank only. The aircraft straightens out on its own, but due to the length of the aircraft, the poor punters at the rear get bashed around a lot on those kinds of landings.

[CaptBlack]

True,True, Uncle Boeing recommends landing on a wet runway with a Xwind with the crab left fully in. With a strong wind, getting the timing right is a risky business.....
Remember MCT a few years back?

[Bally Heck]

Lazlo me old tater.

To ground the pod of a 757 or 767 you would need a bank angle of somewhere around 16 degrees and a pitch angle of between plus 1 and minus three degrees at touchdown. (Varies a bit with type and engine fit but you get the picture)

I submit that if you are in that sort of attitude at touchdown then the crosswind is a relatively minor part of the total challenge on that particular aproach.

You are more likely to ground a slat or flap track fairing.

Might be a bit more of a problem on a 747 though.

HOW I HATE SMART ARSES

[ehwatezedoing]

Or the DC-8 73, probably winner for minimum bank angle on landing .

I don't know if true but I've been told about "8 degres max for banking & 6 for the flare attitude" (or vice versa)

[Prof2MDA]

MD-11 and DC-10 both use the standard side-slip technique, transitioning to it at about 200' AGL. Autopilot does it at 150'.

[airbuswhiz]

I don't know how other fly-by-wire aircraft handle crosswinds, but the A320 is really slick at it. Airbus recommends using the "crab-in" technique right to the point of flaring for touchdown then feeding in rudder to straighten out the crab.

The result is the upwind wing will automatically drop into wind and thus no opposite aileron is required to maintain centerline. Just pull back on the joystick to flare and voila...you're down. It really does work. It does go against what I have been trained to do for crosswinds as has most people here with regards to the opposite rudder/aileron method.

Leave it to Airbus huh..!!

Cherrs,

Airbuswhiz

[jtr]

Isn't the 320 in direct law in the flare?

[avoman]

'isn't the A320 in direct law at the flare?' Not quite. In landing mode pitch attitude is proportional to sidestick movement. Autotrim is inhibited. The attitude reference becomes progressively negative. Pitch ref at 50 ft is moved to -2 degrees from 30ft over 8 seconds. A backward force on the sidestick is necessary to keep the aircraft nose high for the flare. Clever or what?

[jtr]

Sorry, didn't make myself clear.

Isn't the 320 in direct law in the flare with regard to roll.
i.e., once below 100' RA, (is it 100' on the 320?) lateral control reverts to a direct stick to surface relationship, as opposed to a roll rate command when in flight.
What I am getting to is, the wings will not remain level in a x-wind landing when you push off the crab.

[avoman]

Isn't the 320 in direct law in the flare with regard to roll? No, not quite. Lateral control is side stick command to roll rate command in all landing phases to touchdown, same as rest of the flight. Roll normal law. Turn coordination continues. RA doesn't come into it.
In case of failure roll direct law gives side stick position to surface position relationship.
Of course when you kick off drift you will get a secondary roll effect, same as any aircraft.
All pretty academic. Cheers!

[jtr]

Please accept my humble bowing. I assumed <duh> that the flight control PC's were the same/ similar, to those on the 330 and 340, which do exhibit the tendencies I mentioned above. Much apologizing to all I doubted.

grovel grovel etc...

[atomic]

jtr! I know, You were told already.... just to sum it up: When you land, the Bus goes into the flare mode. When you do an autoland, you will see it annunciated on the FMA on your PFD. Somewhere around 40' or 50' the autotrim stops and without going much into detail, it makes you feel like a conventional airplane in the pitch axis so you can grease it on and feel some pressure in the stick to have a feel for landing the plane. Only if you have a dual RA failure does the plane not know what to do when and guess what: Direct Law as soon as that gear comes down. If you gently add rudder during a crab, the plane does pretty well in keeping wings level, but that's in the perfect world. Reality is that you always have to work the ailerons too during x-wind landings, even though you still roll around in normal law.
And back to the first post , in reply to our aspiring airline pilot: Just learn and practice those x-wind landings, you will get the hang of it, because you will have to work those rudders and ailerons, no matter how large your plane. There is no day at O'Hare without a crosswind landing, trust me!