panabiker wrote:
> Over the weekend, I had a conversation with some friends on a recent
> accident involving NJ governor. It was reported by news media that the
> SUV was going at 91 MPH prior to the crash. My question was how they
> found out the speed, and one answer was that a speedometer would stuck
> at the speed the moment of the impact. I find it very hard to believe
> that any speedometer would stuck at the correct reading considering
> the violent nature of the collisions, unless the speedometers are very
> specially designed to record speeds and to sense the crash. Can anyone
> shed some lights on how accident investigators figure out the crash
> speeds?
>
onboard black box.
confession.
measuring skid marks.
recreating the accident scene - how far did the vehicle slide, etc...

but, probably just an educated guess.

Ray