Smart Motorways

[Orionaut]

Three lanes to drive in! Smart lane to die in??

Well, Having just made my first long motorway journey for some years I have now experienced full functional "Smart Motorways" for the first time.

Plus points. variable speed limits properly implemented actually do seem to work pretty well. I managed to drive all the way from SW Surrey to Doncaster and back while experiencing only very little in the way of stop/start driving conditions. My only grumble might be that the VSL isn't aggressive enough IE where conditions demand it, they should be willing to go down to 30MPH or even 20MPH (The speed at which you can achieve maximum traffic flow on a highway in terms of vehicles/hour)

(Wasn't the same for the other side mind. I was traveling "Against the tide" as it were. But nevertheless the extra lanes and VSL systems seems d to deliver the benefits that had been claimed that they would.)

Minus points.

I did indeed come across a stranded vehicle on a smart lane.

I spotted it and slowed in plenty of time (Though I did not at that time have an opportunity to change lanes). What scared the living **** out of me was the antics of the lorry drivers following me.

The first one wasn't so bad, he spotted the obstruction about the same time as I did I guess and was able to pull over into the other lane reasonably easily.

The ones following him, 12 ft apart more or less (Back to that later!) came increasingly closer before spotting the stationary traffic and had to make correspondingly increasingly desperate swerves since, because they were all driving insanely close to one another the following trucks had no idea what was going on until the truck immediately in front of them had changed lanes.

This was in daylight in reasonably good dry conditions.

I shudder to think what the outcome would have been had it been night-time and raining.

Some suggest that why is this any different from driving on a DC, well, there are lots of differences really. I could go into them later but the immediate issue is that yes Motorways are different from the DC experience.

Hard shoulders are there for a reason and removing them was a massive mistake.

The roads needed to be widened, they need to be widened further really (The original 3 lane concept originated in the 1950's FFS, before even)

But doing it on the cheap by removing the hard shoulder is a colossal mistake.

Oh and back to lorry drivers. I know there are lorry drivers here. so you tell me. Why (And indeed how are you able to psychologically) do you guys drive literally for miles in convoys of up to six vehicles (The most I counted yesterday) with only enough space between you to park a mini??

All the following drivers can see are the container doors of the truck in front.

The only information that you have about road conditions ahead are the brake light of the truck in front!

We are not talking a 2 second gap here (Even supposing that two seconds in enough for a 44 ton vehicle in the first place) It is more of a 200mS gap!

I am amazed that accidents are not far more common. And this isn't down to the skill of highly trained professionals here. It is down to sheer bloody luck. And relying on luck to keep you and those around you safe to this insane extent isn't just foolhardy, it is reckless and there should be Police out there stopping those concerned and giving them damn tickets!

 

[Mcnumpty2323]

Have to agree
I hate the hard shoulder as an extra
Lane thing and tailgating
Though to be fair not only lorries
Do it
Wouldn't need smart motorways so
Much
If people actually used them
Properly though

 

[Skilid]

They're a great idea and generally work well. I've had many pleasant journeys on them. The problem isn't the smart motorways, it's the people that use them. People that find them too complicated shouldn't even be behind the wheel of a car. I couldn't believe it when I saw the news stories reporting people didn't understand them. If people stuck to the rules everything would be fine.

I think the only flaw is that if a car breaks down and isn't spotted soon enough on the CCTV to close the lane then it can be dangerous.

 

[iamtheoneneo]

So these smart motorways are not even controlled by AI? wow so clever.

Wouldnt trust them with my life, until a computer actually takes over the slack from some low paid DGAF CCTV checker.

 

[Mcnumpty2323]

Yeah broken down vehicle
Especially in poor visibility is my
Objection
Hard shoulder even on normal
Motorway is such a dangerous place
To be

 

[[TW]Fox]

Why is nobody focusing on the real problem here?

Why are people ending up in stranded vehicles on Motorways?

There will always be a proportion of people who genuinely suffer from a completely unexpected event for which they bear zero responsibility – an incident entirely beyond their control. But what proportion of vehicle stranding events are caused by this/

What proportion of people stranded with a flat tyre after a blowout didn’t check their tyre pressures from one MOT to the next? What proportion of people with a break down had been ignoring a funny noise, water leak, etc etc? How many people get into and drive off in vehicles every single day without even thinking about making sure they are roadworthy? I constantly see people happily driving around in cars with defective headlights, this is probably the tip of the iceberg in terms of the number of people knowingly or negligently driving around in rubbish cars that are a breakdown waiting to happen.

If you think about it the number of potential scenarios that take a perfectly serviceable vehicle from 70mph to 0mph in the space of a few hundred yards are few and far between.

Remember the entire dual carriageway network has no formal hard shoulder either.

 

[MR_Punk]

I was coming down the M6 last week around Birmingham and was annoyed how every gantry seemed to have a different speed limit set, surely this is not good for traffic flow speeding up and slowing down?

 

[vanpeebles]

We will still need hard shoulders for when all the leccy cars start going flat

 

[jamoor]

We will still need hard shoulders for when all the leccy cars start going flat

Indeed and when the cars run out of petrol

 

[Orionaut]

I was coming down the M6 last week around Birmingham and was annoyed how every gantry seemed to have a different speed limit set, surely this is not good for traffic flow speeding up and slowing down?

Don't have time for a full explanation, but that is not how the maths of the situation works.

smooth traffic flow isn't about maintaining constant speed, it is about ensuring that there is sufficient capacity to meet the demands being made.

The relationship between average speed and traffic flow isn't that complicated, but nevertheless, people who have not really thought about it before do find it surprising (A bit like the infamous "Monty Hall" statistical problem, it seems astonishing to begin with but is actually reasonably simple)

VSL implemented correctly and suitably enforced (Either via cooperation# or legal enforcement) actually works really well.

#There really should be more explanation to the wider public as to how VSL benefits them and to explain why it is important to obey seemingly low limits when the roads are still apparently flowing reasonably freely. Its a bit like the Peelian principle. Absence of serious congestion is evidence that VSL is working. To deliver full benefits. VSL needs to be imposed before serious congestion occurs.

 

[Steampunk]

The biggest problem is the same as it's always been: people driving too close to the car in front. This means they have very little reaction time, and are unsighted of what is happening in front of them. If there's a broken down car on what used to be the hard shoulder (where broken down vehicles usually are), then those driving along that hard shoulder will likely not have time to react to it, and those driving too close behind will have even less time. I'm sure we've seen the various dashcam footage where one person swerves to avoid a crash, but the unsighted person driving too close behind has no chance to react and smashes into a stopped vehicle.

If there's one thing that will make smart motorways (and driving generally) better, is for everyone to give more space to allow for thinking and reaction times. Most people's standard of driving and lack of patience is too poor for that, so putting stopped cars in the same place as traffic at motorway speeds was always going to be far more dangerous than reserving the hard shoulder for stopped vehicles.

 

[MR_Punk]

Don't have time for a full explanation, but that is not how the maths of the situation works.

smooth traffic flow isn't about maintaining constant speed, it is about ensuring that there is sufficient capacity to meet the demands being made.

The relationship between average speed and traffic flow isn't that complicated, but nevertheless, people who have not really thought about it before do find it surprising (A bit like the infamous "Monty Hall" statistical problem, it seems astonishing to begin with but is actually reasonably simple)

VSL implemented correctly and suitably enforced (Either via cooperation# or legal enforcement) actually works really well.

#There really should be more explanation to the wider public as to how VSL benefits them and to explain why it is important to obey seemingly low limits when the roads are still apparently flowing reasonably freely. Its a bit like the Peelian principle. Absence of serious congestion is evidence that VSL is working. To deliver full benefits. VSL needs to be imposed before serious congestion occurs.

Appreciate the explanation, it just seems silly to be constantly changing speeds.

 

[DomBruv]

oh,

well

yes

okay.

 

[mccarf]

The last few times I've driven on the M23 towards Gatwick it seems to work quite well. In the mornings I always used to have to queue in lane 1 with all the other people taking morning flights but I haven't had to do that in a few years now since they introduced the smart motorway.

 

[weathmatth]

If smart motorways were implemented correctly in the first place then i think they would have some benefit, have a read of the below. I drive on the M1 (j14 - j6) and then M25 (j21 - j29) a couple times a week, and when there are no broken down cars or incidents then they can sometimes run smoothly, but if anything does happen it all grinds to a holt. And the amount or fatal crashes between J14-J10 on the M1 is worrying.

https://www.bbc.co.uk/news/uk-51236375

 

[Nasher]

They cause more confusion and distraction.

 

[Phemo]

I don't have a problem with them myself. As mentioned by others, the problems are more down to other people. I've had many situations where I've been on a motorway with a variable speed limit set, with the signs clearly saying to use the hard shoulder but you still end up with people in lanes 1 and 2 doing 50ish. My most recent one was being sat in the hard shoulder lane driving at the 60mph limit on the nose and I undertook cars for 6 miles before I had to move into another lane. I had to keep double checking the signs to make sure I wasn't being the idiot, but no the signage definitely said to use hard shoulder.

If people could actually do what the signs told them to do, and drive with correct braking distances, everything would work so much better. But alas, most people are morons.

 

[Orionaut]

If there's one thing that will make smart motorways (and driving generally) better, is for everyone to give more space to allow for thinking and reaction times. Most people's standard of driving and lack of patience is too poor for that, so putting stopped cars in the same place as traffic at motorway speeds was always going to be far more dangerous than reserving the hard shoulder for stopped vehicles.

There also needs to be more observation by drivers in adjacent lanes and a greater willingness to allow people to change lanes at short notice.

A driver in L2 is actually more likely to spot a broken down vehicle in L1 than the following drivers in L1 (different sight line)

Under these circumstances the L2 driver should really try to make space for L1 drivers to change lane (By slowing a bit, opening up gaps and changing lane themselves if possible and allow them to do so rather than just ploughing ahead and doing the "You shall not Pass, Driver" thing because it is "Their" lane! )

(And even if drivers are not prepared to do this because it is the decent thing to do, they should do it for self interest too. If a panicked L1 driver does serve into L2 in front of you, or collides with the stationary vehicle and spins it out into the centre of the motorway, then the slower you are going, the less it is going to hurt!)

 

[Maundie]

The problem isn't smart motorways it's the drivers who aren't smart, I've lost count of the amount of times lorry or van drivers are hammering down the inside lane when it's got an x on it to show it's closed.

 

[Jez]

The only thing which i dislike about smart motorways is the constant need for user input on my non radar cruise car. Very annoying to be needing to constantly input on a motorway journey as a result of changing overhead gantry limits.

Wish it was standard on all cars list: Radar cruise, and the ability for the cruise to react to speed limit roundels.