The car that hit me slammed on the brakes, skid for 100 +/- feet on dry pavement, and still hit me hard enough to spin my Chevy Avalanche around so hard that it knocked one of my tires off of the truck. How do I figure out how fast the other driver was going?
2007-02-28 05:33:51 · 6 answers · asked by BRENDAN F 1 in Cars & Transportation ➔ Safety
It would take an automotive expert - you never mentioned what kind of car it was, and the size and type tires it had, how good its breaks were, etc etc. And your tire falling off has nothing to do with speed, you can pop a tire off going 15 miles an hour then hitting a sewer at the wrong angle.
2007-02-28 05:40:45 · answer #1 · answered by brian 3 · 0⤊ 0⤋
There are calculations that the police can make, but there is no formula that is completely accurate. They can only get an estimate without doing a comprehensive chemical analysis of the tyres to determine the actual friction co-efficient of those specific tyres on that specific road surface. I once had a car that could do what you describe, and at only 40 mph. The tyres were old and the rubber had gone hard - I'd still be doing 35 mph after a skid that long. Tyre type, brand, traction rating and age - as well as vehicle weight and road surface - all play into it.
However, the computer that operates the airbags (in most cars) will record the vehicle speed for about the last 5 seconds before impact - this is what it uses to determine whether to inflate the airbags, and how fast to do so. The police can often get a dealer to download this info for their investigation. (I came across a case like this recently. A couple of guys were having a drag race, and one crashed. He claimed he was doing about 55 at the time of impact, but the computer gave his speed as close to 100 mph. He got busted big time.)
2007-02-28 06:11:39 · answer #2 · answered by Me 6 · 0⤊ 0⤋
If the car did not have anti-lock brakes, it's possible to calculate this from the skid marks. The police may have already done this in their invesitgation, but if not, there are engineering consultants you (or your attorney) can hire to do the inviestigation. If you know what you're doing, it's pretty simple (if the cop at the scene did a proper investigation). However, this isn't a task for amateurs, since that would not hold up in court. Good Luck.
2007-02-28 05:39:53 · answer #3 · answered by JeffyB 7 · 0⤊ 0⤋
You need to have an Accident Reconstructionist check out your accident. Most police deparments have at least one accident investigator on their deparment and some departments even have an accident reconstructionist. If the police agency that investigated your accident has a reconstructionist, ask if that person could further investigate your accident further. Reconstructing an accident is pretty technical stuff and has to take many factors into account; the drag on the pavement, where the initial impact took place, the final rest of the vehicles involved, etc. This is not something that just any ole' person can do.
2007-02-28 05:48:04 · answer #4 · answered by ? 7 · 0⤊ 0⤋
You must know the weight of the other vehicle, and also the weight of your vehicle, for starters.
If you know the make and model of both vehicles, plus add weight of drivers and passengers in each vehicle....
You must be accurate in the skid lenght as this is very, very important in the equation.
After you have this, add it to your question and we'll go from there.
2007-02-28 05:41:15 · answer #5 · answered by Anonymous · 0⤊ 0⤋
This site should give you a good estimate... I figured about 50 mph
http://www.e-z.net/~ts/speedch.htm
2007-02-28 05:42:14 · answer #6 · answered by double_klicks 4 · 0⤊ 0⤋