The aircraft are design with directional stability in mind, and the fuselage forms apart of the aircrafts ability to maintain heading along with the ruder. Any crosswind will act upon the fuselage/rudder and if the wind is strong enough, move the aircraft off heading. The resistance offered by the fuselage will try to maintain heading.
A gust of 50+ knots is enough to move smaller aircraft like a 737/C-130 whilst on the ground. The aircraft can not move back as it would try to do in flight. The nose wheel will move/turn as the fuselage moves despite being connected to a tow bar/tractor.
I have seen aircraft tied down with chains at the nose and tail and still move in high winds, breaking chains (10,000lb strain rating) and damaging landing gear struts in the process. Generally the heavier the aircraft, the higher the winds need to be before it will move. We (RAAF C-130 SQNs) had a habit of refuelling the aircraft if high winds were forecast along with tieing them down to prevent the aircraft from moving. Unfortunately some wind gusts were late notice and we could do nothing but watch.
They are lucky no passengers were disembarking/boarding at the time and no baggage was being loaded with the appropriate GSE in contact with the fuselage.
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