Motorway driving habits.

[ashkeba]

A particular hate of mine when joining a motorway (or A road), is getting stuck behind a car that doesn’t use the slip road to accelerate to road speed, but pootles down it at 25-30mph, leaving you trapped behind them trying to merge into a lane of traffic going twice your speed, so dangerous!

Bad driving by you to be so close behind another cat on a slip road. You need four to six car lengths headway at 60 mph, so slow down at the top of the ramp and let them get well ahead, then press the gas.

 

[bramling]

Bad driving by you to be so close behind another cat on a slip road. You need four to six car lengths headway at 60 mph, so slow down at the top of the ramp and let them get well ahead, then press the gas.

That’s easier said than done. Round here if you attempted to do that it’s guaranteed someone behind would simply go round you and fill the gap, probably beeping and swearing at you in the process.

Humans are wonderful aren’t they?!

 

[Domh245]

Or of course, you accelerate along the slip road assuming the car ahead will be doing the same, and only as you begin to close in on them do you realise that they're ignoring the highway code. On shorter slip roads, you're then rather limited in being able to back off to get a gap

 

[ashkeba]

Or of course, you accelerate along the slip road assuming the car ahead will be doing the same, and only as you begin to close in on them do you realise that they're ignoring the highway code. On shorter slip roads, you're then rather limited in being able to back off to get a gap

Like the film says, assumption is the mother of all F ups.

 

[Bletchleyite]

It's not the gap that is the main issue, the main issue is such a slow vehicle, attempting to join the motorway at below 56mph i.e. lorry speed, is causing a serious danger to those behind them.

If you don't have the confidence to use the motorway correctly, don't use it. Take some lessons and practice with a qualified driving instructor first.

I'd like to see prosecutions for dangerous driving for doing this, as that's exactly what it is. If you don't like motorways there is literally always an alternative option.

 

[nlogax]

That’s easier said than done. Round here if you attempted to do that it’s guaranteed someone behind would simply go round you and fill the gap, probably beeping and swearing at you in the process.

Exactly this. Where I live almost any gap between me and whoever's in front is seen as opportunity for overtaking vehicles to nip into. Doesn't matter if the gap is a car length or a single metre. London area drivers have always had a death wish and an apparent desire to be at their destination half an hour before they've even departed.

 

[Peter Mugridge]

Bad driving by you to be so close behind another car on a slip road. You need four to six car lengths headway at 60 mph, so slow down at the top of the ramp and let them get well ahead, then press the gas.

I had an unbelievable one once in a two lane slip onto the M25 anticlockwise from the A217.

Slow car doing only about 20 in the left hand lane, me doing about 50 and accelerating in the right hand lane. I was about 30 feet away from overtaking the slow car when the driver suddenly moved over into the right lane in front of me, only indicating after starting the maneouvre. Fortunately there was nothing else behind me as I slammed the anchors on - I reckon I came within a few inches of the moron's rear bumper.

 

[Domh245]

Like the film says, assumption is the mother of all F ups.

Indeed, although you'd like to think that ability to follow the highway code is something you could assume of other drivers, although every mile I drive reminds me that isn't the case!

If you don't have the confidence to use the motorway correctly, don't use it. Take some lessons and practice with a qualified driving instructor first.

Fully agreed. I do find the 'stigma' around motorways driving odd though, the first time I drove on a motorway I found it surprisingly easy given how often you hear about people with no confidence in motorway driving. I don't know if that's just because I'd spent lots of time in the front of a car doing motorway trips, or that I'd done quite a lot of driving on NSL dual carriageways whilst a learner or some other factor though

 

[AM9]

That’s easier said than done. Round here if you attempted to do that it’s guaranteed someone behind would simply go round you and fill the gap, probably beeping and swearing at you in the process.

Humans are wonderful aren’t they?!

I prefer slip roads to either be single lane, e.g. if you know it: M1J6 southbound. The sharp double bend from Mount pleasant Lane means that most vehicles start from about 30mph so they can only be reaching 50'ish by the time the LH lane can be accessed, then about 120m later the slip starts narrowing. If there's a large (or just slow) vehicle in front, it's better to ease off and accelerate straight into the second lane.
The other slip type that works is the split into two single lane entries. Ones that come to mind are those at M25J22 eastbound and M11J6 northbound. It is very unlikely that somebody would cross from the first slip to the second or vice versa even if you lay back to get clearance of a slow vehicle in front. Trying to encourage a vehicle to go faster from behind is both hazardous and usually pointless.

 

[bramling]

It's not the gap that is the main issue, the main issue is such a slow vehicle, attempting to join the motorway at below 56mph i.e. lorry speed, is causing a serious danger to those behind them.

If you don't have the confidence to use the motorway correctly, don't use it. Take some lessons and practice with a qualified driving instructor first.

I'd like to see prosecutions for dangerous driving for doing this, as that's exactly what it is. If you don't like motorways there is literally always an alternative option.

Excellent post, IMV this sums things up perfectly.

 

[bramling]

I prefer slip roads to either be single lane

I agree with this. I don't really get why they were ever provided in the first place, as they seem to cause problems now. With motorways having got busier the last thing needed is two side-by-side vehicles trying to join at the same time. Needless to say this isn't what is meant to happen, but it does. The A1(M)'s Stevenage junctions are terrible for it.

The other slip type that works is the split into two single lane entries.

That works well when they both join the left-hand lane. The A1(M) has a bizarre version of this going northbound at Hatfield, where the right-hand lane on the entry slip-road joins the motorway at the point where it increases from two to three lanes. So traffic heading down the right-hand lane on the slip-road will find itself in the middle lane. Add in the tendency of people to wish to move to the right as soon as they join the motorway regardless of whether they actually need to or not, and for some vehicles already on the motorway to move to the right before the junction again regardless of whether they actually need to or not, and it causes a lot of problems. Wouldn't be a problem if people were more competent at driving of course.

 

[Bletchleyite]

I agree with this. I don't really get why they were ever provided in the first place, as they seem to cause problems now. With motorways having got busier the last thing needed is two side-by-side vehicles trying to join at the same time. Needless to say this isn't what is meant to happen, but it does. The A1(M)'s Stevenage junctions are terrible for it.

Agreed, most European motorways have single-lane slipways and they are much safer. Overtake once you've joined the motorway. The one exception would be where you've got two lanes on approach that then split either side of a traffic island and join the motorway separately.

 

[telstarbox]

This is the relevant design guidance for slip roads if anyone's interested:

http://www.standardsforhighways.co....c design of grade separated junctions-web.pdf

 

[The Ham]

This is the relevant design guidance for slip roads if anyone's interested:

http://www.standardsforhighways.co.uk/ha/standards/dmrb/vol6/section2/CD 122 revision 1 Geometric design of grade separated junctions-web.pdf

Which are practically brand new, as they were only released last month.

 

[AM9]

This is the relevant design guidance for slip roads if anyone's interested:

http://www.standardsforhighways.co.uk/ha/standards/dmrb/vol6/section2/CD 122 revision 1 Geometric design of grade separated junctions-web.pdf

Interesting. So what I was trying to describe is officially called a 'ghost island' taper.

 

[MotCO]

Interesting. So what I was trying to describe is officially called a 'ghost island' taper.

Ys, but was it a lane gain with ghost island offside merge, a lane gain with ghost island nearside merge, or a mainline lane gain and double ghost island merge?

 

[AM9]

Ys, but was it a lane gain with ghost island offside merge, a lane gain with ghost island nearside merge, or a mainline lane gain and double ghost island merge?

M11J6 northbound is a lane drop followed by a single lane taper merge from the M25 CCW then a lane gain 2-lane taper merge from the M25 CW - I think.
M25J24 eastbound is a single lane taper merge.
I was obviously remembering somewhere else with a ghost island, but the learning process has been interesting thanks to the linked document provided.

 

[DerekC]

I can feel a new game coming on - "Spot the Junction!

 

[AM9]

I can feel a new game coming on - "Spot the Junction!

Akin to the Bradshaw's parlour game played in 'All Gas & Gaiters'?

 

[brendarick778]

As an ex van driver in man and a van company I would agree that everyone should be mostly worried about their own behaviour on the road.

 

[D365]

As an ex van driver in man and a van company I would agree that everyone should be mostly worried about their own behaviour on the road.

I’m not sure about that. It’s true to an extent, but if I see someone who clearly is lacking in the driving skills department, I’ll give them an extra wide berth...

 

[underbank]

I’m not sure about that. It’s true to an extent, but if I see someone who clearly is lacking in the driving skills department, I’ll give them an extra wide berth...

I taught my son to drive and told him all the time to watch out for idiots and stay away from them - stay further back, take a wider overtake, etc if there's an idiot in front. Slow slightly and allow more room in front if there's a tailgater behind. I basically taught him to drive using the Institute of Advanced Motorists methods - i.e. the system, observation, etc. He went on the motorway in the afternoon when he passed his test on the morning -no problems at all.

 

[Bletchleyite]

I’m not sure about that. It’s true to an extent, but if I see someone who clearly is lacking in the driving skills department, I’ll give them an extra wide berth...

Primarily don't be an idiot, but almost equally importantly watch out for everyone else being an idiot too and give them space to do it without getting angry (anger causes poor decisions), just accept that you make mistakes too.

I actually think that failing to act defensively where you could have done so should cause you to become liable for part of the insurance cost[1], and should also potentially render you liable to DWDCAA/dangerous driving if the avoiding factors were particularly obvious. For instance if you are at lights in the left hand lane with a grass verge don't be so close to the car in front that you couldn't unilaterally turn up onto the verge if you see someone approaching behind so fast they obviously won't stop. You are watching rather than pratting with your phone, aren't you?

[1] If everyone had to claim on their own insurance for their own damage, a lot of people would think differently about how they drive. I've lost count of the number of times I've heard "it doesn't matter, his insurance will pay". It DOES matter. It is incumbent on EVERY driver, rider and pedestrian to avoid collisions if there is any safe way they can do so within the law. They cost the economy money and more importantly they kill people.

 

[underbank]

I actually think that failing to act defensively where you could have done so should cause you to become liable for part of the insurance cost[1], and should also potentially render you liable to DWDCAA/dangerous driving if the avoiding factors were particularly obvious.

I agree with that. When I did my advanced driving training, it was drummed into me that it doesn't matter whose fault an accident was. What matters is whether YOU could have done something to avoid it happening, even if it was 100% the other driver's fault. I'd rather not have "it wasn't my fault" engraved on my coffin! And yes, that includes looking all around you when stationary in a traffic jam, traffic lights, etc., to see if YOU need to take evasive action if something is about to happen. I know for certain that I've prevented tailgaters from hitting me from behind on motorways. Whenever I get a tailgater, I slow slightly and create a longer gap between me and the car in front. Many times that has enabled me to avoid harsh braking when the vehicle in front has braked hard, i.e. instead of me jamming my brakes on to stop within the usual 2 second car length and the car behind ramming me, it's meant I could brake less harshly, giving time to the car behind to brake too!

 

[Bletchleyite]

"Here lies Bletchleyite. He had the right of way".

Not what I want on my gravestone.

 

[MotCO]

I taught my son to drive and told him all the time to watch out for idiots and stay away from them - stay further back, take a wider overtake, etc if there's an idiot in front. Slow slightly and allow more room in front if there's a tailgater behind. I basically taught him to drive using the Institute of Advanced Motorists methods - i.e. the system, observation, etc. He went on the motorway in the afternoon when he passed his test on the morning -no problems at all.

Basically anticipate everything, and assume everyone else is an idiot until you know otherwise.

 

[Bald Rick]

M1J6 southbound. The sharp double bend from Mount pleasant Lane means that most vehicles start from about 30mph so they can only be reaching 50'ish by the time the LH lane can be accessed, then about 120m later the slip starts narrowing.

Only just seen this - if they are only reaching 50 then they are not trying hard enough! Although it does seem to be the modus operandi.

 

[D365]

Only just seen this - if they are only reaching 50 then they are not trying hard enough! Although it does seem to be the modus operandi.

I agree entirely. There are far worse slip roads on the A1.

 

[Meerkat]

Try the clockwise onslip at J9 M25 Leatherhead!
Off the roundabout, round a corner (and the muppets won’t accelerate round a corner....), then a short sliproad uphill with only very late visibility of the traffic you are trying to merge with. It’s prime territory for the panicky to get to the end of the sliproad and stop, and at busy times you basically have to rely on the professionalism and courtesy of the lorry drivers to let you out.
You can’t win - i try to come off the roundabout slow so I have space to get up to a reasonable speed then floor it, but if the muppet in front doesn’t accelerate (or even slows down when they can’t see a huge gap) you have to be fairly forceful and mess up someone on the motorways braking distance.

 

[Bletchleyite]

I agree entirely. There are far worse slip roads on the A1.

Leicester Forest East southbound was a classic but I think it's been extended. In a reasonable car it took a lot of effort to reach 70mph by the end of it.