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masklinnyesterday at 10:14 AM2 repliesview on HN

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.


Replies

moralestapiayesterday at 5:06 PM

>25mph is the final ground speed

Wouldn't final ground speed be zero?

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cucumber3732842yesterday at 10:36 AM

Pause the video at 13 sec. That firetruck is awfully intact for something that allegedly got hit at high speed. Basically just a bunch of top side sheetmetal damage (concentrated to the rear, obviously). In any case it didn't even get sent hard enough to screw up the cab exterior. And on the flip side, if you keep cranking the speed up you start getting to where the plane starts looking too suspiciously intact. There's just not much room to work backwards from the apparent results and get a high difference in speed or get very high initial speeds (100 onto 75 or whatever). If the plane was going fast the truck had to be going fast too or there'd be more carnage. But if they were both going fast you'd expect more damage from the after the fact barrel roll and the plane and truck to be a little farther apart in distance.

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