Does a tailgater fill your wake? :)
 

Wouldn't they need to be way too close? I was reminded of this when I drove home tonight and an SUV was way too close. Then I wondered if anyone ever actually gets close enough to hit the other car.

What is the correct procedure in that case? Normally, I would hit the brakes and pull over, but that would just make the damage worse, which might be okay, if you can get them to cover the repair bill.

The fun part was seeing light shine through red and blue plastic on top of the roof. The police finally went around.

I had my cruise control set to fifty-five in a fifty-five.

With passenger cars ? They should close in to about 3 ft before the lead vehicle gets any advantage from the drafting.

On a motorcycle, you can feel a semi a bit sooner.

A few folks on here have been rear ended IIRC.

I remember research on a group of cyclists revealed that the best position in a group is not at the back, but just in front of that; what made the difference was the other cyclistst bow wake which the last in the group obviously cannot use.
The wake was said to extend almost indefinitely forward, but gets insignificant if you're not close by. In a group, the wake and the draft of the object ahead can have a combined (positive) effect.

If you get hit you will usually come loose again. No need to hit the brakes while still attached, you might lose control.

My wife's aunt was hit on the motorway by a truck when traffic slowed down.
Her Renault Twingo came loose only to be hit again, now on the drivers side; the grill logo filling her door window.
Was pushed around like that for over a kilometer, until her wheels were worn so far down that the bottom of the car touched the pavement and began to smoke heavily.
The truck driver, who was just keeping up with the next car in front, finally noticed the smoke and honking, gesturing and signaling drivers and went to the emergency lane to investigate.

My wife's aunt came out of it shaking but unhurt. Bought a bigger car.

Wow!! what a description and good luck for her. got to watch the rearview just as much as the front when your driving slowly I guess. I seem to get a negative effect when people get a certain distance, say 50 ft back , coould be something there but hard to judge/

according to my UG, i can be as far back as 25 feet or more to catch the benifits. i don't see any reason to be any closer than 2-3 car lengths. i turn off the cruise by pushing in the clutch, slow down till they have no other choice than to go around me. caltrops would help also.

I am sure glad that she was okay! That accident sounded very confusing and terrifying!

Somehow, I visualize the car getting pulled to one side if I braked after being hit and was hit again, and then rolling over.

When you're the one following, right ?

But for the lead vehicle to get any benefits, you'd need to be far closer.

What if a passenger car is following a big rig (safely or dangerously)? What benefits would the truck see, if any?

I have often visualized someone trying to persuade a trucker to tow his car, explaining that the car would fill the truck's wake, while negligibly increasing the mass.

Honestly, I do not think that it would work unless you could somehow attach the car with the tires on the rear of the trailer. Got it, I am awesome at parking!

Sure...

The air right behind the truck will be very turbulent and by and large move with it, so the car will hardly build up a wake.
So, the truck has no profit whatsoever.

Two trucks following each other close by, that's another story.

yes, as far back as 25 feet.
i don't see any benefit when someone is tailgating me. it just upsets me.

The draft wake of a semi extends much further than just 25 feet. I can see the effect at 50 meters, my usual drafing distance.

Ever stood close to a road on a windless day when a semi passes at speed?
You can feel the wake wind blow for 3 or 4 seconds after the semi went by.

Back to the OP's original question, tailgaters should never be viewed as doing you a favor, aero or otherwise.

In aerodynamics, although the trailing car sees some benefit at not-entirely-unsafe-distances, this is relatively untrue from the lead car's point-of-view.
http://i1271.photobucket.com/albums/...ead2/Gaps2.jpg
(This is from aerohead's magnificent trailer gap reference post that I keep citing.)

In terms of liability, I think traffic officers will almost always find the trailing car at fault for a rear-end, but I wouldn't take it as a given unless you run a dash-cam-DVR, i.e. you can prove that you did not swerve and/or brake-check. I see it as a big headache at best, also an opportunity to meet and greet with the most hot-headed segment of the population.

As I read that image of lead and trailing cars, it suggests that the lead car benefits substantially, by nearly .09 in Cd at the closest range represented without practically touching bumpers.

Christofoo, thanks for sharing that! I had seen it before, but must not have paid attention! :)

Much like geese , where the lead goose and his close friends get the easiest and lowest drag flight position , the geese swap positions so every goose benefits in the end.. Hey I think I see Packs of speeding cars doing this all the time , if only by accident , pun intended.

I was traveling with my son in law following for 3 hours on the highway and I picked up 2 mpg from what we had averaged the week before with nobody consistantly following. He wasn't that close, but my daughter told him a few times to back off so he was closer then 2 secs.
In stock car racing everybody gets their drag reduced, frobt, middle, back. On the highway it's not going to be as drastic but now I'm happy to see a follower.

Until he misses the driver 1 up from you who in his stupidity stops hard & fast for a squirrel stopping on the road , and Slams into your rear end at 65+ mph.


We never plan on having an accident but a tailgating really does make having one much more probable and painful.


The tailgater is no small threat to a life , he is in a position to compact a already compact car with someone or a family inside of it ... Makes much ore sense to buy a awesomely fuel efficient economy car , that does not require drafting to 'get ' some acceptable gas mileage.

Play it safe and safety follows instead of the other way around ,..

http://ecomodder.com/forum/member-fr...6245-gaps2.jpghttp://ecomodder.com/forum/member-fr...e6244-gaps.jpg
Hucho via aerohead

www.youtube.com/watch?v=00zd8g1jQ-E

I guess what is the definition of a tailgater? I still say there is a benefit for both front and back at a normal rush hour following distance and even something at the 2 sec distance. Actually tailgater's often pay close attention to what the car in front is doing and if you think about it, in the even of a panic stop the differential in speed would be less because the car in front can't get to zero before the collision happens. If they are following back further an all relaxed not paying attention, the car in front can make a full stop and a full speed collision can happen. I normally don't tailgate because I like to set cruise and not have to mess with speed adjustments but if somebody drives behind me I'm OK with that also.

I was following a dump truck once at a reasonable distance. A rock that was wedged between the rear dual tires cut loose. I watched it make a bee-line for the hood right in front of my windshield. It looked to be about the size of my fist.

It being a Beetle with a rounded hood, the rock bounced sideways and tore the rear view mirror right off the car.

Even on a good day, drafting causes a lot of road rash by every little thing up to hunks of tire tread.

The guy in the wheel chair must of filled his bag .. It is sad no one took the initiative and flagged the semi over- heartless *******s haha


I Bet the semi did not gain much by drafting the chair

I LOL'd.