Wet Road + Wet Grass = ?

[maxrpm]

http://www4.ncsu.edu/~wewebb/P1010199.JPG
http://www4.ncsu.edu/~wewebb/P1010200.JPG
http://www4.ncsu.edu/~wewebb/P1010202.JPG

[maxrpm]

http://www4.ncsu.edu/~wewebb/P1010206.JPG
http://www4.ncsu.edu/~wewebb/P1010215.JPG
http://www4.ncsu.edu/~wewebb/P1010218.JPG
http://www4.ncsu.edu/~wewebb/P1010224.JPG

[Keith-02Accord]

Dood, that totally sucks

Where were u? How did it happen?:(

[maxrpm]

lol, as Shaggy would say "it wasn't me". I'm just sharing some pictures I found on another board.

[Logan]

I didn't know that golf course roads double as road-race circuits.

[ice/solo racer]

You know what I find funny? -- the cop measuring the skid marks,hope he isn't going to try and guess the speed the guy was travelling.
Cops doing that at accident scenes has always kinda bothered me a bit,does the cop know what that kinda grass with that exact amount of moisture has for a friction coeffecient?or how much grip the tires on the car offered at on that surface?or even the exact weight of the vehicle?
OK I'm done now,just pointing out a pet peeve:D

[AlienDNA]

Originally posted by ice/solo racer
You know what I find funny? -- the cop measuring the skid marks,hope he isn't going to try and guess the speed the guy was travelling.
Cops doing that at accident scenes has always kinda bothered me a bit,does the cop know what that kinda grass with that exact amount of moisture has for a friction coeffecient?or how much grip the tires on the car offered at on that surface?or even the exact weight of the vehicle?
OK I'm done now,just pointing out a pet peeve:D

You would be very surprised how close they can get. Physics is an unforgving mistress. Plus, its SOP.

(source: all the damn Mounties in my family)

[Cheers!]

what do they do when there are no skid marks? ie ABS

[ice/solo racer]

Exactly my point-too many variables,physics can only work so well if you don't know all the exact values to use.

[northern911]

When there are skidmarks, we have a weighted device to pull along the exact surface at the exact time, which will give pretty accurate readings.
Most importantly, traffic types like to see measurements for everything. They look pretty on reports.
That way a scene could be recreated should something else come up later.
But really, it just beats standing around deflecting cracks about jelly donuts and requests to arrest annoying neighbours.....:rolleyes:

[Carguy]

One of those traffic cops saved me a lot of hassles (legally speaking) when I got hit in a sweeping curve a few years back. He told me that they are taught vehicle dynamics in different collision scenarios and that includes analyzing and measuring skid marks and reconstructing the accident based on testimony and final vehicle positions.

Here's how it went:

During a morning drive into work, on a dry road with a long sweeping curve I was surprised by some dude in a Caddy crossing over the line into my lane. He had the inside lane and I was going in the opposite direction. I reacted and swerved right, but too little too late and he clipped the rear wheel of my '89 Civic Sedan (4th gen?) - no contest. After the dust settled and my rear bumper stopped spinning, he gets out of the car and accuses me of crossing into his lane!!??? :confused: I was about to loose it on him but instead I found a residence nearby and asked to use the phone - no ubiquitous cell phones at the time.

When the cop arrived he proceeded to ask all the right questions to both of us, etc. Then he returned to me and said that according to the tire marks I had swerved into his lane. He pointed to the tire marks and sure enough I had gone into the other lane. WTF? :confused: I was really pissed at this point and I insisted that he had crossed the line and re-iterated that I could not have made the marks before we hit. :mad: After a little back and forth arguing he further reconstructed the accident by determining the point of impact - before the tire marks - yes! :D The explanation was that after the impact my car pivoted and pointed toward the inside lane. Momentum carried the car over the line and as I was braking and turning back into the outside lane I left tire marks in a fishtail pattern on the road from the inside to the outside lane and finally settled on the side of the road.

The cop finally charged the Caddy driver and his insurance picked up the tab. It turns out he was on medication and had fallen asleep at the wheel. :rolleyes:

[J.C.]

If changing from tire A to tire B can reduce stopping distances or allow greater cornering speeds how can they possibly say what speed someone was travelling? IMO they guesstimate as it is the only solution and it is upto you to argue and prove to them if you feel they are wrong. Wheather or not they will listen depends on if they believe you.