I’ve been waiting with bated breath for this video to get posted. This may be the single most epic 11 Foot 8 crash ever.
I don’t know how fast that semi was going to 1) run that light while it was still yellow – every other laser-sensor triggering red-light-runner I’ve seen has ended up running the light while it was VERY red, and to 2) almost clear the crash bar entirely.
This looks like a standard length semitrailer, so call it 53 feet.
Immediately before hitting the crash bar, the semitrailer passes a fixed point on my screen in 16 frames.
The Youtube video is rendered at approximately 15 frames per second.
D = RT, so R = D/T
R = (53 feet)/(16/15ths seconds) = 49.69 feet per second, which is (“just”) 33.9 miles per hour. (Speed limit on Gregson is 25.). Still surprised it cleared the yellow light, though I guess the driver could be slowing down by the time the truck enters the frame.
(The above assumes that the playback speed of the video is equal to the true speed, which I guess we don’t really know.)