Crosswind landing practice

Your incorrect in your statement. The video you refer to is flight test certification testing the side-load limits of the landing gear for certification purposes. We still use the crab to a sideslip in jumbo jets as the preferred method in crosswind landings. It is not good on the equipment and it is uncomfortable for the passengers feeling the airplane yaw violently as it corrects itself.

 

Having worked on the -80, KC-135, 707,et al I remember that crosswind landing loads were carefully and seriously considered in the design of the main landing gear in face of the short ground clearance especially on number 2 and 3 nacelles. An upwind wing could not be lowered by much, maybe 6 degrees, and an engine strike was omnipresent and they did happen even from non-crosswind landings. The side struts on the main gear and the truck beams were way over designed and never failed in a crabbed landing. The tires withstood extreme skidding as the airplane straightened out but they were designed for it.
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The preferred crosswind method is to align the longitudinal axis with the runway in all airplanes in crosswind landings prior to touchdown regardless of the design limits of the a/c. The exceptions being airplanes without 3 axis controls such as the aircoupe.

It can be done with side slip method or aligning the a/c with the runway just prior to touchdown using rudder alone which requires a great deal of skill and timing.

The autoland computer on the 747 and DC-10 both a/c that I have flown use the side slip method to align the aircraft with the runway prior to the flare. The a/c does not land in a crab!

Although some aircraft (B-52 and C-5A) were designed to land in a crab and have landing gear that rotated to align with the runway to eliminate the stresses imposed on the gear and tires associated with high gross weight landings.

Landing in a crab is horrible on tires and I do not know of an airline that teaches this method? The airplane hops repeatedly and rotates violently as it aligns itself. My passengers do not enjoy this and as their Captain strive to give them the smoothest ride I can. I have landed the DC-10 in over 50 knot direct crosswinds using the wing low method.

Here is a pic of a 747 doing it right.
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I guess I sounded like a crabbed landing was the accepted wasy to land a large tricycled gear airliner. I don't fly these things like you do and don't counter your statement. I was merely implying that the landing gear is designed to react the loads that are imposed by mistreatment. Slapdown, dropped in landings, and loss of directional control, are some of the considerations that are designed for, neither of which are normal operating procedures. During certification of airliners they are put through every bad technique or condition that can be devised and that is what the airplane is designed to.
The B-52 suffered from one major problem, the tandem landing gear. It required the huge vertical tail to maintain directional control on or near the ground. When the castoring gear ( slaved to rudder postion ) was installed they could keep the nose into a crosswind and affect a crabbed landing and the tall tail was shortened. The airplane is also impossible to rotate off the runway like a normal trike-geared affair due to the extreme aft position of the aft truck. That's why the inboard wing has a 7 1/2 degree angle of incidence so it can levitate into the air on takeoff. They fly level with the nose hanging down about four degrees.

 

Yes indeed. I am very familiar with the certification of airliners.

My Father flew Flt. Test for McDonnell Douglas for 26 years and I have amazing videos of what they put the DC-10, KC-10 and MD-11 through to earn their certification. The landing gear high sink rate and sideload tests were amazing to watch from ground level as well as the VMU tests and full VMCA testing.

The flight crew wore parachutes and had explosive charges on the door and ropes going down the fueslage to get out in case they entered a spin. They flew the airplane at the very limit of the envelope.

Average line pilots do not know how far above the envelope they operate their machines, which makes commercial aviation a relatively safe environment. The DC-10 and MD-11 went Mach 1 in the certifiation program. That is well above their normal operating regime.

Here is a pic of the MD-11 when it earned Certification. The guy in the orange jumpseat on the right with the hat is my Dad whom I consider to be a reputable source of information regarding certification of airliners.

Cheers
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Thank you, Paul. I worked for Boeing for 40+ years and was associated in many ways with flight test and training. It is true that people including pilots have no idea of what an airliner goes through to be certified. The number one 777 was a mess when it came back to Everett for refurb. Now you and your dad can teach me some things.
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Your welcome. Glad to add to the discussion.

The airplane you see in the pic went to World Airways. The front part of the airplane was full of wrinkles from the pounding it took from the autoland flight test. It was tripping off early in the program and slamming down rather hard. Hard enough to wrinkle the skins near the nose! They got a very good deal on the plane though.

Paul