DAL 747-400 scrapes an engine

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Quote: Looks to me like a VERY firm touchdown... with no correction at touchdown for the wing low crosswind technique....

would be interested to know what the winds were at the time of the incident
Quote: for the same reason '130 guy' said this....
As I said, it looks like an over correction of aileron since you can see the right spoiler panels increase after touchdown. In other words, instead of the typical error of relaxing crosswind controls upon touchdown, the pilot increased the right bank. And as others have suggested a maximum of 5 degrees bank, well, we see the results.
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Because of the right aileron input during the touchdown, the ground spoiler deployment occurs first on the right wing. This seems to increase the bank further and the engine hits the ground.

The 74 lands nicely in a crab with the body gear able to swivel and straighten out the ground track on touchdown. We always were taught to land it in a crab.
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Quote: I would be curious to know the criteria used to establish the bank limit. I'm not so sure it would be combined with dropping it in, and bending the wing as was demonstrated in the video.
Boeing's FCTM has a graph with a list of notes:
Pitch about the aft body gear centerline
LE flaps fully extended
Aileron full down
Roll around wing gear outside tire
Stabilizer full nose up
Elevator full down
Struts compressed
Flaps 30

It shows you'll drag a RR pod with 6 degrees bank at 5 degrees pitch up or about 5.5 degrees bank at 8 degrees pitch up. P&W and GE engines give you an extra degree of bank before impact. Another chart gives tail clearance. Five degrees up gives 55 inches clearance, eight degrees up give 30 inches and ten gives 10 inches clearance.
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Quote: Because of the right aileron input during the touchdown, the ground spoiler deployment occurs first on the right wing. This seems to increase the bank further and the engine hits the ground.

The 74 lands nicely in a crab with the body gear able to swivel and straighten out the ground track on touchdown. We always were taught to land it in a crab.
What if the Body-Gear Steering is MEL'd and disabled? Been too many years; can't remember the implications.
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Quote: What if the Body-Gear Steering is MEL'd and disabled? Been too many years; can't remember the implications.
Body-Gear Steering enabled on speed decreasing thru 15 knots, de-activated accelerating thru 20 knots.
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I used to take LTs out in a truck to side of the runway (well clear, but a good view) while the local pro did xwind landings--made them cautious!

The initial touchdown looked well within 5 degrees, but when it bounced, really just got light on its "feet" the deploying spoilers and aileron started the roll into the wind. No 744 experience, so no guess as to control wheel position.

GF
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