Nick,
it does show a strength of the BK-117 C2 because it DOES meet the latest crashworthy fuel design requirements, so it would have a much lower probability of burning in a post crash fire
I suspect that there's a tad of thread creep: the aircraft is a BK-117B, or B2 but definitely not a C2, so the strength of the original design is well proven. When I ripped the tail rotor gear box out of my 117, after landing and spreading the cross tubes everything was still functioning to the extent that I put the engines to ground idle, and started a 2 minute countdown for the turbines. Until I realised the clonking noise was the tail rotor drive shaft (or the remains of....) thrashing around in the vertical fin
The strength of the BK hull is very impressive, and this reinforces my opinion
