Tailgate and speed

Strider590

You know when your driving on the motorway and all 3 lanes have slowed to a crawl for no apparent reason? and then suddenly clear up?

Reason = somebody brake tested a tailgater 2 hours earlier........

Jamie_Carter

Strider590 wrote: »

You know when your driving on the motorway and all 3 lanes have slowed to a crawl for no apparent reason? and then suddenly clear up?

Reason = somebody brake tested a tailgater 2 hours earlier........

No, it's usually down to people driving far faster than the flow of traffic. Then they have to brake, and there is a knock on effect down the line of traffic that was trying to go faster than everyone else. If they had all been travelling at around the same speed, with a safe distance between them, then the traffic would flow smoothly.

So don't blame the person who doesn't like someone driving a few feet from their bumper, blame the tailgater who is trying to bully his way past.

smashingyour...

Jamie_Carter wrote: »

No, it's usually down to people driving far faster than the flow of traffic. Then they have to brake, and there is a knock on effect down the line of traffic that was trying to go faster than everyone else. If they had all been travelling at around the same speed, with a safe distance between them, then the traffic would flow smoothly.

So don't blame the person who doesn't like someone driving a few feet from their bumper, blame the tailgater who is trying to bully his way past.

Are you saying strider is wrong?

Strider590

What i'm saying is that there should be no reason to use brakes on a motorway AND when people brake it has a knock on effect for hours and hundreds of cars behind. As the length of the brake press gets longer and longer back down the motorway, someone changes lanes, someone else brakes and it spreads until an hour later the people who were 70 miles behind are crawling to a stop a mile or so away from where the first person used their brakes.

It comes down to chicken and egg:
If someone wasn't hogging the lane, would they have been tailgated?
If the impatient Audi/BMW driver wasn't tailgating, would the person in front have brake tested them?

Are accidents caused by people overtaking, or by people doing 30mph below the speed limit?

There are a lot of these questions when it comes to motoring and everyone is very quick to pass blame, when in fact it often takes two to cause a problem.

Jamie_Carter

Strider590 wrote: »

What i'm saying is that there should be no reason to use brakes on a motorway AND when people brake it has a knock on effect for hours and hundreds of cars behind. As the length of the brake press gets longer and longer back down the motorway, someone changes lanes, someone else brakes and it spreads until an hour later the people who were 70 miles behind are crawling to a stop a mile or so away from where the first person used their brakes.

It comes down to chicken and egg:
If someone wasn't hogging the lane, would they have been tailgated?
If the impatient Audi/BMW driver wasn't tailgating, would the person in front have brake tested them?

Are accidents caused by people overtaking, or by people doing 30mph below the speed limit?

There are a lot of these questions when it comes to motoring and everyone is very quick to pass blame, when in fact it often takes two to cause a problem.

Yes I know exactly what you are saying, and in essence you are correct, except for the 'hour later' bit. It is more likely to be a few 100 meters back at the most.

Variable speed cameras are designed to keep us all at a steady speed. And if we all leave the correct space between vehicles, then all the traffic will flow smoothly. It's usually (not always) the tailgaters (who are usually the ones trying to bully you out of the way, so they can go much quicker), who have to slam on their brakes, because they haven't left themselves time to react. This then causes the knock on effect you describe.

smashingyour...

Jamie_Carter wrote: »

Yes I know exactly what you are saying, and in essence you are correct, except for the 'hour later' bit. It is more likely to be a few 100 meters back at the most.

Variable speed cameras are designed to keep us all at a steady speed. And if we all leave the correct space between vehicles, then all the traffic will flow smoothly. It's usually (not always) the tailgaters (who are usually the ones trying to bully you out of the way, so they can go much quicker), who have to slam on their brakes, because they haven't left themselves time to react. This then causes the knock on effect you describe.

It's often over several miles, unless you know better.;)

Lum

smashingyour... wrote: »

It's often over several miles, unless you know better.;)

Does the distance back really matter? It's the stop/start wave that is annoying, not the exact location that it happens. That makes no difference unless the wave happens just after the exit you wanted

Joe_Horner

Got to agree with jamie here - it doesn't need someone barke testing a tailgater to cause that effect. All it needs is any change of speed and the tailgater(s) themselves do the rest.

When someone is doing 80mph with a 0.5 second gap to the car in front, they tend to be concentrating so hard on that car - out of necessity - that they don't react to a change of speed ahead until the car they're following does. That means they have to react much more than if they were holding back, and the one behind them reacts even harder. That's where the wave starts.

You can demonstrate this (safely) in slow moving traffic. Rather than crawling along stop-start 6 foot behind the car ahead, let the gap open up to 40 or 50 feet. If someone drops into that gap then ease up and let it open again - it'll make virtually no difference to your journey time doing 5mph instead of 10mph for the few seconds it takes for the gap to re-form!

You'll find that you can usually keep rolling even when those around you keep having to stop (slowly killing their clutches and brakes in the process) because you just ease off as they brake, and they're moving again by the time you might need to stop.

Good gaps = better traffic flow at any speed.

alastairq

Good gaps = better traffic flow at any speed.

I agree..however, when someone decides to pull out immediately in front of me, when I am travelling fast enough to be overtaking them [and the vehicle in front of them], then I have to use the brake..or risk running into the back of them.....especially when they don't actually do much to increase their own speed, to get past the vehicle in their way?

If some sad sack in a BMW happens to be coming up behind me, and not reading my situation, then they end up braking even harder.

Luckily, I am now ahead of the inevitable braking queue rapidly forming behind me.

Talking of 'sad sacks'.....there a sad sack BMW Z3 driver on the M5 this morning, north-ish bound..got pulled by an unmarked plods-r-us BMW....came past me like a dose-of-salts, and my speedo was reading just under 80.....the blue lights came on right in front of me...[I knew it wasn't for me anyway....].....everybody around backed off dramatically,except me..I changed to the overtaking lane, and disappeared...as I often do.

Came across an Audi thingumegig that had just been pulled by another unmarked BMW, a while later.

The Fester did rather well, considering it was full of camping gear....

Joe_Horner

alastairq wrote: »

I agree..however, when someone decides to pull out immediately in front of me, when I am travelling fast enough to be overtaking them [and the vehicle in front of them], then I have to use the brake..or risk running into the back of them.....especially when they don't actually do much to increase their own speed, to get past the vehicle in their way?

True enough.

Which is why, in the Driving Nirvana I mentioned before, people leave enough gap in front and don't pull out (or in) to leave an unsafe gap behind.

Ultimately, all multi-vehicle crashes are caused by cars driving too close to each other (think about it!) so, imho, doing so deliberately should be the number one traffic crime!