So if I'm going to be rear-ended...

Yesterday 120-km/h traffic slowed to 10 km/h RIGHT NOW in my lane. (No reason for this that I ever found out.) I hit the brakes hard (obviously) and so did the guy behind me. No options for grabbing any other real estate left or right. For about a second I thought the guy behind me wasn't going to stop before arriving in my trunk or back seat. So, question: if a crash is coming from behind, what's the current thinking on what to do with yourself? Push yourself back into the seat & headrest? Try to relax? What?

If my 10 seconds of thinking about physics is correct; Hit the car in front of you just before the inattentive driver hits you, this will effectively up the mass of your vehicle and lessen the impact to you and the occupants.

Edit: Unless the vehicle is big/fast enough that your car is going to be crushed to a point that the cabin will be compromised significantly, then you're berkeleyed no matter what unless you have a few hundred feet in front of you.

Pretty much back in the seat tand try to go as limp as possible.

Try to have your head securely back against your headrest, as most injuries in rear end collisions tend to be whiplash related.

Hitting the car in front of you... wouldn't reccomend it. Why? the lighter mass of your car can be moved by the collision, which dissipates the kinetic energy from the vehicle hitting you. If you are instead sandwitched between him and another car, the only dissipation is your car crumpling.

The crashes that hurt the most are the ones where you come to a dead stop.

Let go of the wheel and hope that you're not a lazy berkeley like me who carries a bunch of unsecured projectiles in the back of the car.

That's a toughie. I'm curious as to what the correct answer is.

My thought is to try to relax against the seat, so that as your car is accelerated by the impact, you are accelerated with it, rather than having the seat catch up with you when it's already got a head start on acceleration. The seat, and the car it's attached to are going to be accelerated a certain amount by the impact. The more of that time you can spread your own acceleration out over, the better.

I got rear-ended in a similar scenario. Traffic stacked up suddenly, I stopped. I was trying to stop short of the car in front of me but no shorter than needed so the person behind me in the S-class Merc would hopefully not run into me. They succeeded, but the pickup behind them didn't, and shoved the Mercedes into me, but I didn't get shoved into the car in front of me.

Coincidentally, the car in front of me did hit the car in front of it. Conditions were kind of wacky (sunny/rainy/accident miles up the road causing funny patterns), and there were no fewer than three separate accident groups on the shoulder within easy view, and I watched two more happen while waiting for my tow...

But I digress... I think Kenny's probably right about the "ideal" if you're going to get rear-ended being to contact the car in front just as you stop, prior to impact from the rear. To Apexcarver's point, unless it's something big enough ahead and behind to accordion your car, you want the energy to go into crumpling your crumple zones, and not into accelerating your body...

OTOH, it probably depends on how hard you're going to get hit and by what, and what's in front of you... If the vehicles ahead and behind are big and heavy and still moving fast, I think I'd rather start the impact as far back as possible so the car doesn't get crushed as badly with some energy going into dragging my car along (assuming I can keep my foot on the brake).

In reality, not sure I'll get a chance to calculate, and not sure there's an ideal one-size-fits-all. Guess I'll try to watch for escapes (not always there), and generally try to stop before I hit what's ahead of me, and hope whoever's behind me at least manages to scrub some speed before impact...

I've been in three car accidents in my life. All three were getting rear-ended, totaling one '69 dart, one '71 2002, and one '87 325is (was driving the 325is in the scenario above). The only injury was a friend riding with me in the Dart (no headrests) who didn't know we were about to get hit... His neck bugged him for quite some time after that. I guess seeing the headlights disappear behind the trunk gave me enough notice to hold my head so it didn't get tossed around too badly. Probably dropped it forward some and tensed my neck a bit? In the 325is, I'll never know for sure what would have happened, but I'm awfully glad I swapped out the stock seat with the tired tilt mechanism for a new Corbeau...

Apexcarver wrote: Pretty much back in the seat tand try to go as limp as possible. Try to have your head securely back against your headrest, as most injuries in rear end collisions tend to be whiplash related. Hitting the car in front of you... wouldn't reccomend it. Why? the lighter mass of your car can be moved by the collision, which dissipates the kinetic energy from the vehicle hitting you. If you are instead sandwitched between him and another car, the only dissipation is your car crumpling. The crashes that hurt the most are the ones where you come to a dead stop.

This. No question about it.

ransom wrote: To Apexcarver's point, unless it's something big enough ahead and behind to accordion your car, you *want* the energy to go into crumpling your crumple zones, and not into accelerating your body... OTOH, it probably depends on how hard you're going to get hit and by what, and what's in front of you... If the vehicles ahead and behind are big and heavy and still moving fast, I think I'd rather start the impact as far back as possible so the car doesn't get crushed as badly with some energy going into dragging my car along (assuming I can keep my foot on the brake).

You do have some points there. I mostly am looking at preventing intrusions and limiting damages. It depends much on the vehicles involved. In a modern (last 5-10 years) the safety system is advanced to a point that the acceleration of your vehicle transferring into you is not as likely to injure (seat/restraint system support is pretty good with newer regulations on headrests for this type of accident)

Older vehicles, especially ones without headrests, are a different matter. That said, I still worry over intrusion, because it is much more likely on an older vehicle. Crash structures have come a long ways. So I would probably still lean towards not hitting the car in front of you.

Likely thing is that theres gonna be nothing you can do about if you are or are not into the vehicle in front of you anyways, so mostly a moot point.

neck injuries are the biggest problem in these crashes, unless there IS damage intrusion into the passenger compartment, then all bets are off.

If you're going to get rear-ended, you should really take some time to think about the decisions you made that brought you to this point in your life. You should also fight back as much as possible, no sense they take it without a fight!

Wait, what were we talking about again?

Oh.

Yeah, um, press on the brake, put your head back, drop your arms and try not to tense up too much.

Mythbusters anyone??

turboswede wrote: If you're going to get rear-ended, you should really take some time to think about the decisions you made that brought you to this point in your life. You should also fight back as much as possible, no sense they take it without a fight!

"There's always time for lubricant"

In reply to JoeyM:

Love that movie.

Thank you.

When the Trooper got nailed from behind I just saw a tan flash in the mirror then BANG! so that means neither my daughter or I were tensed up. Her seat was fine; the seat back on mine broke.

Solution: Always be in the left lane with a shoulder. Come in handy more than once.

Obviously not always possible.

ransom wrote: ....Conditions were kind of wacky (sunny/rainy/accident miles up the road causing funny patterns), and there were no fewer than three separate accident groups on the shoulder within easy view, and I **watched two more happen** while waiting for my tow...

http://www.eskimo.com/~billb/amateur/traffic/traffic1.html

DrBoost wrote: Mythbusters anyone??

BINGO!

I was told that its best to get off the brake if you're about to be rear-ended and allow yourself to roll into whatever's ahead of you.

Preferably, I always like to leave myself an out, if its possible.

you should be drunk. those shiny happy people never get hurt.

Giant Purple Snorklewacker wrote: you should be drunk. those shiny happy people never get hurt.

BANGO!

Apexcarver wrote: Pretty much back in the seat tand try to go as limp as possible. Try to have your head securely back against your headrest, as most injuries in rear end collisions tend to be whiplash related. Hitting the car in front of you... wouldn't reccomend it. Why? the lighter mass of your car can be moved by the collision, which dissipates the kinetic energy from the vehicle hitting you. If you are instead sandwitched between him and another car, the only dissipation is your car crumpling. The crashes that hurt the most are the ones where you come to a dead stop.

It is at this point I would like to point out that Apexcarver kinda sorta does this stuff for a living, so we should probably listen to him.

The one time I was struck in the back of my vehicle while stopped, I had no idea it was coming, so I wasn't tensed up at all. I have zero injuries from that incident.

Giant Purple Snorklewacker wrote: you should be drunk. those shiny happy people never get hurt.

yeah, but then it all becomes your fault somehow...

Use the Bob Hoover method of crashing a plane: " Fly as far into the crash as possible."

or...

Racer1ab wrote: I was told that its best to get off the brake if you're about to be rear-ended and allow yourself to roll into whatever's ahead of you. Preferably, I always like to leave myself an out, if its possible.

Out of the 4 times I've been rear ended, two I saw coming and did this. No pain or whiplash later and the damage was far less to my vehicle than when I didn't see it coming and stayed on the brake. On a side note.. Always take the extra insurance when your on vacation in Cali, apparently their legal liability coverage is stupid low at $5000. I learned the hard way. My uninsured motorist coverage thankfully covered the remainder.

Thanks, all. Now that I've had more time to think about this, I remember reading somewhere about the Flying Squad of engineers at Mercedes-Benz in Germany who are sent out to inspect accidents involving M-B vehicles in case there's something they can learn. The article said that these engineers' cars were easy to spot in the employee parking lot because they all had their headrests adjusted up & forward as much as required. Headrests rule. (So does keeping an exit route handy at all times, but it's not always possible, let alone practical.)

Just hang on because there will always be a million things that don't rush through your head. Last time I had been rear-ended (the only time), I had blood squirting out of my face and I still wonder how. I'm just glad I still have the eyet that was barely missed.