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cucumber3732842yesterday at 10:07 AM2 repliesview on HN

The results seem on the high end but they check out at first glance.

A plane is basically a flimsy tube. A firetruck is a solid brick comparatively. The plane out weighs the fire truck by a lot and out speeds it by a lot. So yeah, destroying the whole front of the plane to punt the truck it sounds about right for a 25 on 5 or 35 on 10/15 type rear ending to me. Flipping doesn't really sound that unreasonable considering that the plane made contact with the top of the truck (just by virtue of comparative height) and contact may not have been straight on. Even if it left the pavement on it's wheels airport firefighters aren't exactly who I'd bet on (they're middle of the pack) to keep the truck on it's wheels if they got surprise kicked off the road especially if there's an embankment involved.


Replies

masklinnyesterday at 10:14 AM

A CRJ 9000 is 70000 lbs empty, 84500 lbs MTOW.

An Oshkosh 1500 4x4 is 62000 lbs GVWR (wiki says kerb weight but it’s incorrect).

The plane was landing and the truck was heading to an intervention, so they were likely close to empty and to GVWR respectively.

And again, 25mph is the final ground speed, after the plane punted the truck and kept on going for 600ft.

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ErroneousBoshyesterday at 10:09 PM

> A firetruck is a solid brick comparatively.

I think you'd be surprised. The cab is quite solid because it has to conform to certain vehicle design and safety criteria (at least here in Europe).

The rest of it is made of fairly squashy aluminium box section with panels TIG welded on. There's not a lot left if one of them gets rolled, for example.