Poor pilot technique. Transport aircraft are designed for alot more side loads on the main landing gear. Ask Skyguy how you land a 747? Leave it in the crab, kick rudder at the last second and let inertia do it is work... plane will straighten out itself. They finally changed our Ops Manual and put in a max X-wind limitation when we went to CAT II operations (27 kts, 15 kts for Cat II). Prior to that, I believe the highest x-wind component I landed in was 43 kts, plus gusts (can't remember).
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