Safe Speed Forums

It isn't. I see it this way, there are 3 types of tailgater...

1. Aggressive 'get out of my way'. This type justifies his/her actions to him/herself by thinking that the car they are tailgating should get out of the way. No point emphasising 2 second rule to these morons, their own sense of self-importance will override it.

2. Thumb up ass, always drive this way, never had an accident, not really thinking about their driving and thus didn't realise I was tailgating type.

3. Anally retentive type. See the flow of traffic as a queue and if they leave a 2 second gap, someone else less sensible than them will nip in and pinch it leaving them to re-establish the 2 second gap and going backwards (I have heard people use this term even though they are obviously still traveling forwards at 70 odd mph) as a result. So if everyone else is driving like that , I might as well, its unrealistic not to.

Types 2 and 3 can probably be lectured or taught the error of their thinking, types 1's...well how many do your boys lecture each day IG?

Any tail gaiting legislation/enforcement must also address the morons who drive constantly in the lane of their choice with no regard for lane discipline.

If lane discipline were enforced there would be precious little tailgating.

We do target on our patch. Usual procedure is lecture and undue care/careless charge - dangerous if we can make it stick - but this is not very often. This usually bursts their balloon! Agree - these are the one who shoot themselves in foot as soon as they are stopped ! On aggregate - manage to cop some of them if we are lurking nearby. Sometimes the mere presence on the road appears to help as well. Believe that Germans use combination of CCTV/VCS and their BiBs - based on what my cousin (one who lives there) was telling me last week. Would have no real problem with a tailgating camera used as proper tool in this way.

Similarly - would pull someone sat hogging a lane as well. Believe we pull a few of those each day too.

Trouble is - even in area which is still fairly well staffed - we still do not have enough to be on each and every road all the time. But we know and target the obvious danger zones. As soon as another potentially dangerous site is identified - we target there too.

Can only do best we can - and we do seem on average to be doing better than others! (According to our stats - anyway!)

Well said. Please can we do something about dickheads who sit in the middle/outside lane when they're not actually overtaking anything! I've yet to see a copper pull someone for this!

I beg to differ. To my mind, one of the main reasons for strings of traffic with each tailgating the one in front (e.g. the outside lane of almost any motorway at peak times) is that there is insufficient network capacity. Neglecting the length of the vehicles themselves, each lane of motorway has a capacity of thirty vehicles per minute. I've stood on a motorway bridge and counted over seventy on one occasion and regularly count over sixty per minute. This isn't "blips", it's constant streams of tailgating vehicles. If everyone stuck rigidly to the two second rule, the network would gridlock.

So, the Government fail to deliver their promises and seek yet again to penalise the innocent.

For the record, I live by the two second rule and abhor tailgating -- but without adequate roads I can understand why it happens.

_________________
Will

Nope you are talking about congestion, not tailgating. these are very seperate issues. but I do agree with you, if that makes sense.

Well, I've used the term "going backwards", though I was exaggerating. It is a problem though, and especially in lane 2 due to the MLOC and in lane 3 due to everyone having to go round the MLOC. Sometimes I prefer to simply avoid the motorway altogether, leave earlier and go on the back roads. Easier to keep to the 2 second rule, less stressful and often more fun.

_________________
Make everything as simple as possible, but not simpler - Einstein

I don't think that tailgating and congestion are very separate issues. While some people (morons) will tailgate come what may, I'm convinced that lack of road capacity causes the majority of tailgating incidents. Of course, here I'm defining tailgating as following the vehicle in front at less than the recommended separation (two seconds in ideal conditions).

As I wrote in my previous post, the maximum capacity for any lane (be it motorway, dual or single carriageway) is 30 vehicles per minute. If you take vehicle length into consideration, that drops (IIRC 28 per minute at 70mph to 20 per minute at 10mph assuming an average vehicle length of fifteen feet). If more than that number attempt to use the road, two things happen

• tailbacks occur as vehicles wait for the capacity to carry them without tailgating
• the "system" adapts to accommodate the extra traffic by reducing inter-vehicle distances (i.e. tailgating occurs)

Currently, a mixture of both happen. If we totally prevent tailgating, the tailbacks must get worse, and I suspect that would bring this country to its knees.

You may think that slowing down the traffic would create more capacity because slower traffic means less distance between each vehicle, which means more traffic on each mile of road. However, while the road has more vehicles per mile, ironicaly the capacity (in terms of vehicles per minute) has dropped. This is because vehicle length is more significant at lower speeds. So, slowing down the traffic (whether it's a tailback or a deliberate measure by the authorities) actually reduces the number of users a road can carry in safety.

So, congestion (aka inadequate road capacity) causes tailgating and the tailbacks serve to make matters even worse.

_________________
Will

That a well thought out argument but in reality irrellevent. The vehicle load you describe is only an issue at times of congestion when by the very nature of traffic flow the speeds are reduced.

You never hear people complaining about tailgating in the context of traffic jams as the distance that a tailgater would leave becomes a safe distance in the mind of even the complainer.

The issue with tailgating is when traffic is flowing freely eiter at, close to or even above the speed limit and a driver uses his vehicle to intimidate the driver in front to move out of the way. This has the effect with some people with others it hasthe reverse effect.

Now I do not condone tailgaters at all but I can sometimes see their point. FWIW I ride a bike everywhere, dont really take the car anymore. I see the tailgating all the time. Normally there is at least on clear lane beside the front car to the left, and the driver is just "lane hogging".

What is meant to happen? everyone winds up just sitting behind these morons (they are normally just below the speed limit and definately below the "safe-speed". Eventually the anger of the following car driver leadds to the tailgating.

Now not all occasions follow this path, but most do. The same is the case when M/C overtake to the left (not talking filtering here). If there is room for me to pass you on the left thats really where you should be driving as you are not overtaking.

Many years ago I saw a police range rover on the M6 divinbg along and when he came across a member of the middle lane owners club he got infront of them and used an illuminated sign to tell them to move to the left lane. Trouble is that now a days they are not there

A correspondent to our local paper stated that:

In conversations I have had with serving traffic police officers through the course of my job, they are convinced that the capacity of the motorway network could be increased if motorists would treat them as a single lane highway with two overtaking lanes. i.e. when you have finished your overtake, move back to lane to your left. People don't do this then whinge about congestion and tailgating, unbelievable.

He was replying to another correspondent who is convinced that, as long as he is driving at 70mph, he has every right to stay in lane 2, regardless of what is in lane 1. I would love to know where the latter guy got this hopelessly incorrect, selfish and ultimately dangerous idea. As long as we have people driving around with ridiculously skewed perceptions of correct driving behaviour, then we will have frustration and, ultimately, congestion.

When traffic flows to begin to tend towards congestion though, I believe it has been demonstrated that the type of driver behaviour we witness (try to keep going at 80mph, charge up behind the back of the queue, brake, cause the guy tailgating you to brake harder etc leads to the 'unexplained' traffic stoppages that clear for no reason. Many people seem totally baffled by this, failing to link their own behaviour (cause) to the end result (effect).

Maintaining bigger gaps at 80 mph isn't the answer, but slowing the traffic down results in a physically smaller 2 second gap, whilst giving drivers time to react to without overbraking. I think it's been tried on the M25, problem is many people see the 50mph signs (or whatever) can see no reason for them and carry on at 80

This is precisely the situation where tailgating cameras would make a mint, and why I jumped in to highlight this issue.

FWIW, tailgating is never safe to my mind and I always leave a safe distance between me and the vehicle in front. As the traffic bunches up, I leave even more space so that I can afford to brake a little gentler and so lessen the chance that average numpty will rear-end me. Often that means that gap gets filled by someone from the next lane, so I just travel a little slower and the gap automatically restores after each lane hopper closes the gap.

_________________
Will

While lower speeds have a physically smaller two second gap in terms of distance, it's still two seconds. To that two seconds you must add the time it takes for each vehicle to pass a fixed point, which increases as speed reduces. If we assume an average vehicle length of fifteen feet, this increases from 0.14 seconds at 70 mph to over a second at 10 mph. This means that each lane can carry 28 vehicles per minute at 70 mph, reduces to 27 per minute at 50 mph, 25 at 30mph, and just 20 vehicles per minute at 10 mph.

So, reducing the speed actually reduces the number of vehicles per minute that can use the road in safety.

_________________
Will

Whatever the maths appear to show Will, its been demonstrated that slowing vehicle speeds helps ease congestion.

This link http://www.highways.gov.uk/roads/projec ... ual/07.htm offers a small suggestionas to why:



I believe there was a scheme in the USA whereby traffic cops patrolling a notrious congestion hotspot (crossing a bridge) enforced a lower speed limit than drivers would otherwise have attempted to maintain and guess what, the traffic flowed freely over the bridge at a slower but consistent speed.

The key to that is preventing the onset of flow breakdown, which prevents the ripple effect. However, the safe capacity does not increase. What tends to happen is that the traffic settles down so that everyone is doing the same speed and then the inter-vehicle gap reduces. Although the road is carrying more vehicles per unit time, it is at the expense of safety.

Now introduce tailgating cameras into the equation to force everyone into leaving a two-second gap so that the inter-vehicle gap cannot reduce ...

_________________
Will

Correct, slowing the traffic down when volumes get to a certain critical mass has that exact effect.

No - not suggesting Wildcat should have been prosecuted - the collision was obviously not down to her. There will be exceptional accidents when neither driver was at fault but they're rare. Wildcat's was one. But if the driver who piled into the back of her hadn't been incapacitated by illness, he should have been prosecuted. In that case, I guess he probably would have been because personal injury resulted; but if it had been a 'damage only' collision? Is it not the case that police show little interest in 'damage only' collisions. I think that's wrong. If drivers are sent the message that a collision which they caused is no more than 'a bit of bad luck', why should they try to improve?

It may be hard (perhaps impossible) in some cases to allocate blame but in many (most) cases it's not.

Was indeed a rare one in million occurence. Fortunately - she survived it and fully recovered. Will not deny that I had some very bad moments at the time. Apparently this incident is somewhere on list of worst UK accidents - as was incident which killed Ferdl.



Agreed - I would have personally torn him limb from limb. Ironically - he was spotted by Panda before he reached motorway - but he could not stop or did not stop him.....




Apparently one of the reps at Wildy's firm witnessed damage only rear-end shunt at traffic lights. Person was stopped at red light and got rear-ended. Police refused to attend because "no one was injured" - even though the rep thought the idiot had been drinking. That is wrong. There is also the big danger - especially these days that the other party may be uninsured - and you would only find out about that after the event They claim "short staff" . All the more reason to sack all the safety prats and spend the money on providing police officers for this purpose. Even community officers would do for this kind of incident ( )

Paul,

I want to ask you about this comment you made in the thread start:

5) It is reasonable and recommended to adopt a transient close following position in preparation for overtaking. This sort of tailgating tends to represent best practice and should not result in prosecution.

BACK TO ME:

I've always felt that overtaking was best done with a good distance behind the car you are going to overtake and feel that if you sit close you have to tailgate, swerve in and out to see on coming traffic and generally don't get a better view of the road up ahead than if you are back a good distance and that if you HAVE to sit close then the length of road to overtake may not be long enough to safely overtake, in other words the extra distance i'm talking about is used up in the manouvere when a suitable piece of road is found for the overtake. Just my opinion on how I feel about overtaking, not getting at your comment or anything. Would like to hear your comments on my approach.

Andrew

That's my way of thinking exactly. Also, if you're more than two seconds behind the vehicle you want to overtake, you can accelerate so that by the time you reach the overtaking opportunity you have a speed difference that helps make the manoeuvre much smoother and safer (particularly if you're driving a comparitively low-powered vehicle). Also, doing it that way means that if something (e.g. an oncoming vehicle) obliges you to abort the overtake, you just need to lift off the throttle and perhaps dab the brakes to drop back to the "starting" position.

Adopting a close-following position while waiting for an overtaking opportunity is, IMO, dangerous unless you can see well ahead of the vehicle you're about to overtake (in which case, why aren't you overtaking?) because you won't be able to anticipate any emergency braking that vehicle may need to do.

_________________
Will

It's beyond the time I have available this morning to write a full description of overtaking, but see this diagram scanned from Roadcraft:



There are two serious disadvantages in planning to overtake from 2 seconds behind:

1) It might take a long time to close the gap when a short overtaking opportuinity arises - this means missing overtakes.

2) Reducing the time taken to close the gap tends to cause a high speed differential from the "overtakee". This makes you vulnerable to anything the overtakee might do (especially if he suddenly decides to pull out to make his own overtake.

The recommended procedure involves:

1) closing the gap in preparation for overtaking.

2) Pulling out without acceleration when it is safe to do so.

3) Assessing the safety of the overtake from an offside position - you can see MUCH better from the other side of the road in most cases. Only then do you decide to go or to return to the left.

Roadcraft's "overtaking position" isn't clearly defined in terms of gap to the overtakee - I usually pull out from about 1 second behind and accelerate gently while looking for the opportuinity to go. (this isn't in Roadcraft's recommendations). I might sometimes end up holding on offside position 10 feet or less behind the overtakee waiting for the view to clear. If it's a "no" sliding back to the left is trivial, if it's a yes I don't have so far to go to pass the overtakee.

_________________
Paul Smith
Our scrap speed cameras petition got over 28,000 sigs
The Safe Speed campaign demands a return to intelligent road safety