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Rolling A Car Onto Its Side, Minimun Speed Needed?


NateR31
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Cut a long story short, was in a car accident, the other party claimed they were going 40kms, yet they swerved and the car tipped onto its and then slid for 30meters, it was a rav 4 kinda thing,so its not like it was a real 4wd with a high roll rate, but what im really asking is, is it possible to roll a car at 40kms and then slide for 30meters? what kinda speed would be needed to do this? Hope that makes sense...

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It is near impossible to answer that. There are so many variables e.g.

how grippy were the tyres?

gradient of the road?

How evenly the weight was spread in the car?

how heavy the car was? e.g. were there passengers?

speed?

how quickly they turned?

the height of the car?

you get my drift (excuse the pun :/ ) but it's basically impossible to answer that.

I would say though, that having driven 4wds, they are taller, and once the centre of gravity falls outside the base of the wheels, it'll tip. but you'd have to be pretty unlucky to tip it at 40 kph.

especially considering that since it's just a normal road sissy 4wd, it'll probably have fairly ungrippy cars, and it'd be more liekly to slide out than flip (if it's easier to slide, it will slide, if it's easier to flip, it'll flip).

So who was at fault exactly? what happened?

if they just swerved you, and flipped, isn't that tough cookies for them?

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I'm with PHATR32...

Rav 4 = VERY easy to roll.

Thin stance, high for there stance, soft as suspension. Lots of body roll...

I thought I was going to roll my cousins through an intersection one day... And I was only doing 15km/h! That's how badly they roll over!

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I agree with the above that it's possible to tip it, but to slide for 30m going 40km/hr? I don't think so...

and thats the main answer i wanted to hear...

OK turns out it was a CRV, but heres the story on what happend.

Im waiting to turn(so im not moving) she wasnt paying attention and was veering towards me, i was looking the other way, befor it was too late she side swiped the front of my car, swerved and then tipped over and slide down the road..

Shes saying i pulled out infront of her... now me being a) P plater, b) driving a skyline, guess whos side the cops are on, regardless they gave me a failed to give way ticket, and shes saying she has whiteness saying i pulled out, but meh, she can screw herself..

Im just trying to determine what speed she was going, the road was dry, crv has a kerb weight of 1600kg or so, yes its easy to roll them, but slide down the road, youd need some momentum to get you moving, cause i dont think steel and road are frictionless.. :laugh:

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Dude, that stuff they can work out fairly easy hey. Its just some pyhsics stuff hey.

But I am very septical that 30m would be achived in a slide at 40kmh, that said I think it could be done given the right conditions.

Thing is tho, how the hell is it your fault hitting a car that is sliding on its side!?

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i rolled my skyline almost twice (came to a stop on the drivers side and slid for about 15 meters until it hit grass). i was going around 60

dunno if its any help

yeh see, if she said 60 then she would admit to speeding. zing!

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Dude, that stuff they can work out fairly easy hey. Its just some pyhsics stuff hey.

But I am very septical that 30m would be achived in a slide at 40kmh, that said I think it could be done given the right conditions.

Thing is tho, how the hell is it your fault hitting a car that is sliding on its side!?

well i dont know how its my fault, i guess because she dosnt have insurance.

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well i dont know how its my fault, i guess because she dosnt have insurance.

I'd be debating it mate. If it wasn't your fault, don't lay down and take the kick for it. Did you see how far the car slid?

There's no way car doing 40kph has the inertia to hit something, tip on its side, and slide for 30m, assuming its a flat road and not downhill. They'd have to be going faster than that.

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Take it up with your insurance for a no fault claim and fight the ticket. The Police should have photos of the accident site and by you fighting the ticket will have to do their calculations and will be able to estimate the speed of the other driver. Accident investigation unit has all the tools to do this.

Your insurance company can subpoena the photos and calculations for your defence and to stitch the other driver up.

This one is a no brainer unless you were actually in the wrong. Something you have to decide for yourself.

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Take it up with your insurance for a no fault claim and fight the ticket. The Police should have photos of the accident site and by you fighting the ticket will have to do their calculations and will be able to estimate the speed of the other driver. Accident investigation unit has all the tools to do this.

Your insurance company can subpoena the photos and calculations for your defence and to stitch the other driver up.

This one is a no brainer unless you were actually in the wrong. Something you have to decide for yourself.

Touche'

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if she had right of way and witnesses , you are screwed . even if she is obviously speeding or not paying due care its pretty irrelevant in this case . my wife changed lanes and a guy hit her from behind sending the car accross 4 lanes of trafic and writing it off . he was obviously speeding and police acknoledged that but its his lane and his right of way , you have to prove you wernt there , not how fast shes going.

your only hope is to get a couple of witnesses at the scene to testify 100% that you did not pull into her lane and even then youd probably need some physical evidence of such cause her insurance company will fight it all the way especially as shes got witnesses .

if you got insurance bite the bullet and pay the excess . talk to your insurance company but id say they will give the same advise

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NateR31, how far were you into the intersection? Do they have much proof (debris on the road) that you were into the intersection or had moved out in front of her?

Here is some help.

To calculate the speed at which a car will roll over. (simple calculation with basic info taken into consideration). You can use this as part to show if she was speeding.

Also, was the intersection flat/off-camber/bumps? Was it a large radius she was turning? It will take more speed to roll a car around a large radius, but bumps and an off camber road will increase the chance of it happening.

velocity of vehicle(km/h) at which it will tip = 3.6 x (SR of (w x g x r )/(2 x h))

3.6 converts metres per second to km/h

SR = Square root

w = weight of vehicle

g = gravitational acceleration 9.81m/s

r = radius the car was taking

h = height of centre of gravity from the ground (hard to tell, probably 1/2 of the height (or more) of the cars height in the case of a CRV but its safer to calculate it at 1/3 of the vehicle height, maybe Honda can help)

REMEMBER this is an approximation, but it might show she was driving over the speed limit. The more accurate you can get the CoG and the radius she was turning, the more accurate your answer will be.

If anyone wants to tell me if I am wrong, go for it, just what I have learnt from dynamics at TAFE and don't wan't so see someone get screwed over because he drives a skyline and the stupid bitch can't keep her eyes on the road.

(end rant, works been crap lately)

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