Safe Speed Forums

I am sure this subject has been discussed many times already on this forum but being new I would be interested to hear other views on the matter.
As someone who takes a great interest in driving I am shocked at how many drivers seem to regularly tailgate other vehicles.
Not only that but also there are so many that will just not keep a safe distance from the vehicle in front.
My interpretation of the matter is that for a start the 2 second rule seems to be completely misunderstood but that is not surprising the way it is advertised.
The 2 second rule is a minimum distance that an alert car driver should keep from the vehicle in front when driving in good conditions.Trucks and Coaches should at least double that and keep a minimum of 4 seconds.
The way the rule is put across I suspect some drivers think if they are using the 2 second rule then they are keeping a safe distance.
Any other views welcome?

Hi and welcome. Yes I think driving too close is a much bigger problem than the authorties seem to acknowledge (whilst exceeding the speed limit is a much smaller one)! However, speed is easy to measure automatically and tailgating isn't...

I'm not sure 4 seconds is an appropriate minimum for heavier vehicles. Yes, they do take longer to stop than lighter ones, by and large, but not twice the distance!

Hello Mole and thanks for your reply.Yes you are quite correct it seems to be a problem that seems to be ignored.
The thing is most of the tailgaters are the ones that also speed.
I do not know if you have driven heavy vehicles or not but I have and I can tell you a loaded vehicle weighing 38T will take
more far more than twice the distance to stop than any car.
When you brake hard in a car the ABS will kick in and the vehicle will stop relatively quickly but in a heavier vehicle the weight takes over and the vehicle carries on for some distance.
How many LGV drivers have driven at say 55 mph and slammed on the brakes to see how long it takes? I have on private ground and it is frightening how long it does take.It is even more frightening when you see them traveling nose to tail on motorways.The problem is most do it everyday and become complacent.
When it comes to keeping a safe traveling distance with trucks the rule was 40mph....40 metres......50mph......50 metres and so on.
How many stick to that now?

Yes there are many unsafe tailgaters around but the fact is that if you drive any busy motorway using the 2 second rule you will be endlessly cut up. Unintentionally you encourage other drivers to make stupid manoeuvres to get past you to fill the gap they believe should not be there.

The 2 second gap is not a stopping distance, it is to give you reaction time. If you can see past the vehicle in front then you can close the gap without compromising safety. Indeed Roadcraft advocates close following as a preparation to overtake, although not for extended periods of time.

Safety is about reading the situation and adapting, not driving to an inflexible set of rules.

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"Show me someone who says that they have never exceeded a speed limit, and I'll show you a liar, or a menace." (Austin Williams - Director, Transport Research Group)

Any views expressed in this post are personal opinions and may not represent the views of Safe Speed

I think we need to be very careful about going down that route, because whilst I agree it is generally true, it tends to lead to the mindset that speeding is (in itself) automatically dangerous - which, of course, is not a view I share! It would be a bit like saying that most tailgaters are the ones who drive BMWs - yet it's obvious that this, doesn't necessarily make BMWs dangerous!

No, 7.5 tonnes is the heaviest I've ever driven (and I didn't try an emergency stop either)! That said, although I'm quite happy to agree that they will take longer to stop, I'd be surprised if it really was more than twice the distance of a car! Certainly, the people who write the Highway Code are of the opinion that all road vehicles stop in the same distance! I know almost all artics have ABS these days, and ESC is coming soon.

Yeah, I often see the "heavies" following each other down the motorway, on their speed limiters, leaving a gap that I couldn't even PARK in, let alone stop in! I've no idea (a) why they do it and (b) why there isn't a lot more carnage that there seems to be! One thing I WOULD say is that the 40 metres at 40 and 50 at 50 thing is actually potentially quite dangerous though. NOTHING (car or truck) has a stpping distance that goes up in direct proportion to the speed. IF it WAS 40 metres at 40, it would be something like 60 metres at 50, 90 metres at 60...and so on. That's the whole reason for moving towards the "2 second" rule (where the interval between the vehicles is defined as a time) rather than a "distance" rule.

Thanks again Mole for your reply. I will not comment about your view on speeding but I can assure you regarding weight that 40tonnes even with ABS will take more than twice the distance to stop that the average car of 2 tonnes.
Going back to the 40....40.....50....50 thing that has been a rule for years with trucks.It is a recommended traveling distance when going at these speeds and not a stopping distance.Look on the link someone else posted and it says there one yard for every mph which proves my point is correct.

Seen many posts on here giving advice on tailgaiting. Some of the ones by IG are particularly illuminating.

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lets bring sanity back to speed limits.
Drivers are like donkeys -they respond best to a carrot, not a stick .Road safety experts are like Asses - best kept covered up ,or sat on

[Sorry Jack272, I ended up editing your post by mistake whist trying to quote it! Hopefully it is now as you left it?]

What I meant to say was:


I'd be keen to hear more about the tests you did with the 40 tonner. For instance, what was the car used for comparison? I must say I'm really struggling (just from a "laws of physics" point of view!), to understand how the stopping distance can be more than doubled!

As for the 40/40/50/50 thing, it may well have been some sort of rule of thumb amongst truckers for years, but just because someone else believes it's true, it doesn't actually mean that it is! It certainly flies in the face of accepted wisdom - even the highway code quoted stopping distances don't go up in direct proportion to the speed! I mean, you don't really believe the stopping distance (in any vehicle) from 60 is only twice what it is from 30, do you?

The 'thinking' distance does increase linearly so possibly this is where the idea comes from. It might work well when following another heavy with similar braking ability, but not when behind a car.

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Driving fast is for a particular time and place, I can do it I just only do it occasionally because I am a gentleman.
- James May

Possibly geting into "shark infested" waters, but how can a "thinking" distance be quoted for the average person. This is going back to my days on single track roads,where you found the brain had sent the message before the eyes registered the problem.( Forum item on Lizard brain activity). We used to find that locals had little problems, whereas visitors ( possibly from an urban environment) took a lot longer to react.

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lets bring sanity back to speed limits.
Drivers are like donkeys -they respond best to a carrot, not a stick .Road safety experts are like Asses - best kept covered up ,or sat on

Thanks again for your reply.Again you seem to be confusing stopping distances with safe traveling distances.
When a vehicle is doing 60mph then a safe traveling distance from the vehicle in front is 60 metres.
The stopping distance not come into the safe traveling distance.If you keep a safe traveling distance you will be able to stop if something happens.

Regarding the breaking tests all I can say is when you brake very hard in a car weighing about 2 tonnes with ABS the cars wheels will lock then release rapidly until the car stops.
When you do the same with 40 tonnes behind you the weight will not allow to lock and release at any reasonable speed.
The weight of the vehicle takes over an keeps pushing the vehicle forward.Maybe I have not explained that very well but I can only go by what actually happened when I tried it.

The fact of the matter and what gets me is when you see vehicles (cars and lorries) traveling far too close to each other if (and thankfully it does not happen too often) something unexpected happens there is no way they will stop but I suspect with a lot of drivers think it will never happen to them and then when it does it is never their fault.....excuses galore...seen and heard it too many times.....Attitudes need to change.

Jack- me,I'm old school. No ABS ETC when I started driving(not even discs) . So I try not to get too close ,as that's when problems start. Try stopping an old car /van or non disc brakes on old tyres in the wet,on a greasy road(Vans were the worst- nothing in rear,unless you loaded them down, so no adhesion on the rar end). Lesson I learned long time ago is that you never depend on something you need to protect you working. Drive as if the worst WILL hapen, and then if it does, you'll be prepared . I don't trust ABS, it might fail. Other experts on here will tell you that it won't. But if mine fails , I've got a right foot ( and lizard brain) to do the job.

_________________
lets bring sanity back to speed limits.
Drivers are like donkeys -they respond best to a carrot, not a stick .Road safety experts are like Asses - best kept covered up ,or sat on

Good man botach....a bit like myself really.....no sychromesh gearboxes...no hydraulic clutches but I seem to think there was more respect on the roads then but maybe it was easier with less traffic.
I also remember when most lorry drivers kept a safe distance but now it seems its only the odd one that does.There just seems to be so many impatient bullies on the road nowadays giving stupid excuses for their bad driving.
I have seen so much carnage on the roads and the pain and suffering it causes and that is why it makes me so angry to see so called professional drivers driving irresponsibly.Don't get me wrong though car drivers are just as bad.
The only way to prevent more carnage is education and changing peoples attitudes but unfortunately I doubt it will never happen.

I don't suppose it will happen until people start getting prosecuted for it. If someone invented a "tailgating camera" tomorrow (and there was a chance for a "tailgating camera partnership" to make a lot of money out of it, you'd soon see them starting to push that message!

60 metres at 60MPH is almost exactly the "2 second rule", and yes, I'm sure it will be fine in most vehicles in most conditions. The problem with trying to separate the "safe travelling distance" from the "stopping distance" is that you make the assumption that whatever you're following isn't going to come to a dead stop (which is what happens in a pile-up). Most of the time, of course, there isn't a pile-up and 60 metres is pretty generous anyway - not much less than the complete stopping distance quoted in the Highway Code for that speed (and most modern cars can pretty much halve that on a dry road anyway). 70m at 70 is less of a safety margin though, and 80m at 80 is getting quite iffy.

Not sure that all tailgaters are impatient bullies, I think a lot of them are just numpties who don't know any better. Certainly when you see one artic following another at 56 with just a couple of car-lengths between them mile after mile, I don't think the following on is trying to "bully" the other, I just don't think he's every really devoted much thought to what might happen. Part of the problem, I think, is that we just have more cars than we have road. Imagine what would happen if everyone on a motorway kept 60+ metres behind everyone else all the time? They probably wouldn't all fit!

Easy peasy mole.... we can pretty much sell you one off the shelf.

We used to have multi role offence detectors , but they went out of fashion.

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lets bring sanity back to speed limits.
Drivers are like donkeys -they respond best to a carrot, not a stick .Road safety experts are like Asses - best kept covered up ,or sat on

Shhhhh!!!! you'll have Greenshed wanting one!!!!! (Do they work inside a van from a motorway bridge)?!

I'm a bit old skool myself, it was a good while after I started driving before I owned a car with even servo assisted brakes. Oh yes, unladen van rear wheel lockup under braking in wet conditions was indeed a tad ummmm interesting

I agree that many drivers seem to have very little appreciation of adequate following distances, but it is not IMO a simple matter. There is no "safe" distance, it is liable to vary depending on many factors, is there visibility beyond the vehicle in front, is it wet, is the road surface poor, is there liable to be ice, what kind of vehicle are you driving, are you diving an ancient unladen van in the wet! etc etc blah blah ad infinitum .....

What IMO we need is for people to be thinking about their following distance and adjusting it appropriately in an informed manner depending on circumstances. I'd bet a fair few so called "distraction" accidents occur simply because somebody did not adjust their following distance prior to unwrapping that mars bar, fiddling with the radio or whatever, just as something unexpected happened somewhere in front, and therefore had no reaction time. I don't want to start another big debate about fiddling with stuff while driving, IMO it is always a bad idea, but if you must do it, do it under suitable conditions and leave extra room, not at 80 mph behind a van you can't see through or past 10 feet behind it at rush hour on a busy motorway in the pi**ing rain while driving a 30 year old unladen van with dodgy brakes!

Safe following distance varies, it ain't ever a set value for all, and it is IMO dangerous to try to make it one. Though I do think a baseline for inexperienced drivers (e.g the existing 2 second jobbie) to work from is a good idea.

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You only need two tools - WD40 and duct tape. If it doesn't move and it should, use WD40. If it moves and it shouldn't, use duct tape. :0)