Originally Posted by
jimjim1
Youtube allows 0.25 speed (and others). Gear Icon/Speed.
At that speed the nose can be seen to fall off before the fire is visible.
Yes, the fuselage fractures due to the impact on to the runway. That was the reaction to the impact. The fuselage acts like a simply supported beam subject to a distributed load (in this case the fuselage weight x NZ (G) load factor). The simple support is at the interface of ground and tyre. The force finds the weakest point and if the force is high enough, structural failure ranging from material plasticity and bolt failure up to catastrophic rupture, as seen here, occurs.
Often, the weakest point is the MLG joints and the landing gear collapses or punches through the wing, and the fuselage hits the ground more or less in one go, as with the 777 at Heathrow.