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crisso
4th Sep 2013, 15:01
I've tried to find an answer elsewhere on the net but without success to date. On the Northern part of the M25 (and probably also on other recently upgraded sections of UK Motorways), particularly on the stretches where it has been fairly recently widened to four lanes each way - simultaneously there have been fitted numerous overhead gantries. Since there are often the dreaded graduated white markings painted on the road, just after just after same, I assume they're equipped with speed cameras. However, there is no warning 'camera' sign on any of these gantries. Does that mean they're inoperative/not legal yet, etc.?

dead_pan
4th Sep 2013, 16:07
Not driven down that bit of tarmac for a while so don't know for sure, but could it be that they're extending the variable speed limit? Check the rear of the gantries next time you drive past as they may not have anything installed on them yet. If they have, I've always assumed they only work when the variable speed limit signs are in use, however I may be wrong (not been done yet).

AFAIK they don't now necessarily need to display a traffic camera sign to warn motorists. Those accursed mobile speed cameras used by plod certainly don't, although some of these are also using ANPR tech to collect data for tracking stolen cars, car tax/insurance violators etc.

Random SLF
4th Sep 2013, 16:13
They've just added these to the M62 between Bradford and Wakefield, everyone slows down over the white markers so maybe they are Police speed cameras. I thought they just monitored average speeds so that the displayed speeds on each gantry could be adjusted accordingly, wouldn't like to bet though.

UniFoxOs
4th Sep 2013, 16:29
WOW, another speed camera hamster wheel so soon after the last one!

MG23
4th Sep 2013, 16:30
Yeah, when I lived by the M25, I used to brake for the gantries with camera markings, then accelerate back to the same speed as the rest of the traffic.

And I loved the useless variable speed limit, where I'd be stuck in a queue of stationary cars with a speed limit of 50mph, or driving along an empty motorway at night and suddenly faced with a 30mph limit. Do you brake to 30mph and risk someone going into the back of you at 80+mph, or keep going and risk a big speeding ticket?

Halfbaked_Boy
4th Sep 2013, 17:06
I'm friendly with a gent who works for the HA, and according to him, it goes as follows...

Gantry matrix specifies a speed limit surrounded by a red circle - You MUST not exceed this speed. Depending on the police force, the true speed at which the cameras are tripped is about (10% + 2 MPH) of the displayed speed. Some people think this rule is a myth, it isn't, and here's the link -

Road Traffic Offences: Guidance on Fixed Penalty Notices (http://www.cps.gov.uk/legal/p_to_r/road_traffic_offences_guidance_on_fixed_penalty_notices/) About a third of the way down, under 'Speed Enforcement'. Guidelines only, of course, and different forces may differ. Wales is basically zero tolerance.

Gantry matrix specifies a speed limit with no circle around it - You are ADVISED not to exceed this speed. A load of BS basically.

Gantry matrix specifies nothing/is empty. For all intents and purposes the camera is disarmed, BUT you may still get flashed for certain speeds. This of course from a friend so don't take it as testament, but he says he's only ever heard of cameras activated because of speeds above 100 MPH when there is NOTHING displayed on the matrix.

Another snippet of into from him... For those times when the matrix speed limit changes in front of your eyes from say, 70 MPH to 50/40 MPH, there's no need to slam on the anchors. You've got either 1 minute or 5 minutes before the camera switches to the new displayed speed for enforcement purposes, I can't remember which one, I'd imagine 1 minute.

Stay safe!

racedo
4th Sep 2013, 17:51
It depends..............

There are fairly big camera on some gantrys that are visible because they grey and stick up....................they the one to slow for. Generally see it on gantry on opposite side as well.

Krystal n chips
4th Sep 2013, 18:03
I thought it was quite simple....Active Traffic Flow..or something similar....if the speed is shown as, say 40 and surrounded by a red circle, that's the maximum speed limit until you see the next increase / decrease or unrestricted sign displayed......and they do work....heading South on the M6 at Birmingham about three weeks ago on a Saturday, the signs were displayed.....as were the one's on the North bound carriageway....I saw quite a few flashes as the camera's activated.....which will come as a nasty surprise to those who feel they don't have to obey the speed limits for the relatively short time it takes to get through the controlled area.

No sympathy of course.

mixture
4th Sep 2013, 20:19
I'm friendly with a gent who works for the HA, and according to him, it goes as follows...

Gantry matrix specifies a speed limit surrounded by a red circle - You MUST not exceed this speed.

Gantry matrix specifies a speed limit with no circle around it - You are ADVISED not to exceed this speed.

You needed a friend in the HA to be able to tell you that ? Maybe a re-read of the highway code might be in order ? :E

G-CPTN
4th Sep 2013, 20:42
You needed a friend in the HA to be able to tell you that ?

What the HA guy has confirmed is that they are 'following common practice' - it could well have been different such as '10mph above posted limit' or some other formula (though you would be annoyed if you were caught by the standard deviation rather than what the HA guy told you).

AtomKraft
4th Sep 2013, 20:53
I'm glad that I'll soon be away from this (our) bloody Country.

Loose rivets
4th Sep 2013, 21:07
10% plus 2 mph was the old The Association of Chief Police Officers' (ACPO)recommendation for speeding tolerance. Then you'd get some little jumped-up [email protected] in a local station that would decide to nick responsible middle-aged gentlemen at 32 mph. Our local post office clerk. Never-done-anything-wrong-in-his-whole-life kind of chap. Appalling bad judgement, and feeble-minded weakness on the part of the PCs obeying his ranting commands.

G-CPTN
4th Sep 2013, 21:20
Bear in mind that vehicle speedometers are designed such that they do not under-read (the necessary tolerances are set so that they always over-read) so your actual speed will usually be slightly less than the indicated figure).

European Union member states must also grant type approval to vehicles meeting similar EU standards. The ones covering speedometers are similar to the UNECE regulation in that they specify that:-

The indicated speed must never be less than the actual speed, i.e. it should not be possible to inadvertently speed because of an incorrect speedometer reading.
The indicated speed must not be more than 110 percent of the true speed plus 4 km/h at specified test speeds. For example, at 80 km/h, the indicated speed must be no more than 92 km/h.

The standards specify both the limits on accuracy and many of the details of how it should be measured during the approvals process, for example that the test measurements should be made (for most vehicles) at 40, 80 and 120 km/h, and at a particular ambient temperature. There are slight differences between the different standards, for example in the minimum accuracy of the equipment measuring the true speed of the vehicle.

The UNECE regulation relaxes the requirements for vehicles mass-produced following type approval. At Conformity of Production Audits the upper limit on indicated speed is increased to 110 percent plus 6 km/h for cars, buses, trucks and similar vehicles, and 110 percent plus 8 km/h for two- or three-wheeled vehicles which have a maximum speed above 50 km/h (or a cylinder capacity, if powered by a heat engine, of more than 50 cm³). European Union Directive 2000/7/EC, which relates to two- and three-wheeled vehicles, provides similar slightly relaxed limits in production.

Tankertrashnav
4th Sep 2013, 22:58
I really dont know why people get so lathered up about speed limits and spend so much time working out how to break them and get away with it.

Why not try this experiment? (it works for people who have a regular daily commute) For a two week period, drive within the speed limits. Check your journey times accurately and note them down. Then revert to your practice of breaking the speed limits wherever traffic conditions permit. Then check your journey times under the new regime of speed limit breaking.

Given the generally crowded state of our roads at most times, I'd be very surprised if you have saved as much as 10% on your journey time by breaking speed limits, probably a lot less. Over the years I have got into the habit of mentally noting any particularly distinctive car that has overtaken me in excess of the speed limit. I have long since ceased to be surprised by how many times I have arrived at a traffic bottleneck maybe 20 miles down the route and observed that same car a hundred yards or so ahead of me in the queue. That Bentley that hurtled past me at Indian Queens on the A30 a few weeks ago, for example, popped up again a little way ahead of me 15 minutes later as we both crawled into Truro!

Frankly I never bother trying to identify speed cameras - I find it much easier to just stick to the speed limits. Oh, and having no points on your licence does wonders for your insurance premium.

AtomKraft
4th Sep 2013, 23:45
Tanker

What a load of Bollocks.

Most folk just plug along at whatever speed seems reasonable- then get fined!

By all means fine the loony speed merchants..

I canna wait to get way from all this wank. ;)

mixture
5th Sep 2013, 07:12
Why not try this experiment? (it works for people who have a regular daily commute) For a two week period, drive within the speed limits. Check your journey times accurately and note them down. Then revert to your practice of breaking the speed limits wherever traffic conditions permit. Then check your journey times under the new regime of speed limit breaking.

I can agree with this statement.

I once did this experiment (well, wasn't a deliberate experiment, just happened to end up that way) with a friend between a couple of cities in the UK (London and Brighton).

At the time he was driving a top of the range Porsche, I was driving something less exciting, a heavy saloon with a less beefy engine.

He sped off into the distance a the first hint of a dual carriageway and I never saw him again after that, so I assume he wasn't quite doing the NSL on the faster sections.

I strictly adhered to the speed limits, sticking to various advanced driving techniques to "make progress in a safe manner" as they say.

Sure I found him already parked up in the car park. But he had not finished unpacking his stuff from his boot yet .... turns out he'd arrived less than 10 minutes before me.

So I wholly agree with Tanker when he says "I really dont know why people get so lathered up about speed limits and spend so much time working out how to break them and get away with it."

What's the point of trying to find ways to break the law without being caught when the savings are so marginal. Those idiots who slam on the anchors when they see cameras are utter twats and don't deserve a driving license.

As the old saying goes ... "do the crime, pay the time" (or in the case of driving, you could always go live in Germany or the Isle of Man !).

Lightning Mate
5th Sep 2013, 08:42
Cruise control is your friend.

The three-pointed star on the front is even better.

Curious Pax
5th Sep 2013, 08:54
Tanker

What a load of Bollocks.

Most folk just plug along at whatever speed seems reasonable- then get fined!

By all means fine the loony speed merchants..

I canna wait to get way from all this wank. ;)

I'm a careful responsible driver, well able to drive safely at speeds above the specified limit, and any attempt to stop me from doing so is 'wank'. However I see lots of loony speed merchants around me every day....

Surely the ability to drive safely at speeds above the speed limit includes having sufficient awareness of what is going on around you, and the ability to see cameras/speed traps well enough in advance not to set them off. I hold my hands up to breaking the speed limit very regularly, however I also reckon I'm pretty good at spotting the traps, and have therefore never had a speeding ticket in the UK in 30 years of driving. (Probably shouldn't tempt fate, so I'll get one next week!).

When I lived in the Netherlands I did get 4/5 tickets, but unless you really went mad they just seemed to regard them as an extra fee for using the roads fast, so I wasn't as careful as the consequences weren't great. You could even set up a direct debit with the authorities so they could automatically collect the fines from you. Points didn't come into it unless (as far as I could tell) you got up to about double the limit! The local paper in the Hague suburb where I lived seem to have a report every week about a foreign driver getting caught on the A4 doing in excess of 200kmh (they always seemed keen to highlight the foreign bit!).

mixture
5th Sep 2013, 10:25
However I see lots of loony speed merchants around me every day....

And that surely is the problem. They have to legislate for the lowest common denominator.

MagnusP
5th Sep 2013, 10:45
Also, every loony speed merchant thinks that he/she is the only good driver, and it's everyone else who's a loony speed merchant.

Any fule kno that I am, in fact, the good driver; it's you lot causing the problems.

See what I mean? :O

Alloa Akbar
5th Sep 2013, 12:11
I had 6 points on my licence (3 for speeding on the motorway at 82 mph and 3 for being a complete ******** on my R1 in Yeovil - Fair cop!) However I then got 3 more taking me to 9 for doing 74 on the M42 in a 70. I questioned the offence and was told that the 10% + 2 rule is only at the Chief Constable's discretion, and essentially I was shit out of luck. So at 9 points and within touching distance of a ban, I decided speed limits were actually to observed. I survived the 20 months on 9 points, and am now back down to 6, but my driving style remains the same.. I fracture speed limits ever so slightly, but on the whole I am a good boy and I still get to my destination in reasonable times.

Lets be honest, volume of traffic on todays roads makes short blast speeding pointless.

onetrack
5th Sep 2013, 12:28
Trapster is your friend. There's no point in regularly contributing to Govt coffers, merely because you infringed some pointless statutory limit, imposed by some faceless public servant. :)

Speed Trap Sharing System - Trapster (http://www.trapster.com/)

Curious Pax
5th Sep 2013, 12:59
And that surely is the problem. They have to legislate for the lowest common denominator.

I know that and you know that, but I'm not sure about the rest of 'em!

Tankertrashnav
5th Sep 2013, 13:04
Lets be honest, volume of traffic on todays roads makes short blast speeding pointless.


Precisely - plus expensive in fuel costs and engine/tyre/brake wear and tear.

onetrack - my comments are aimed at drivers in the UK and NW Europe (German autobahns excepted) where traffic levels frequently reach saturation point. I'm assuming roads in Western Australia are somewhat emptier - even I'd be tempted to floor it crossing the Nullarbor!

Just thought, I wonder if any of those drivers on the Sheppey crossing this morning will admit they were driving too fast. All those interviewed said they had been shunted from behind - but nobody seemed to think that they were at fault for hitting the car in front!

Captivep
5th Sep 2013, 13:35
Tanker - absolutely agree with you.

On a journey of 100 miles, the time difference between averaging 70 mph and 80 mph is about ten minutes...

onetrack
5th Sep 2013, 13:50
Tankertrashnav - Unfortunately, the W.A. Police are particularly intent on catching speedsters, even along that tedious run known as the Eyre Hwy.
If you floored it across the Nullarbor, I could pretty well guarantee you would be relieved of a sizeable sum of money before you could travel very far!

To them, it's a matter of trying to reduce the road toll - as many drivers lack the necessary control skills to keep their vehicle upright and pointing in the right direction - even on a straight, flat, monotonous stretch of outback highway!

If excessive speed is added to the equation, then there is almost certainly a much higher level of fatalities when they roll over.
The limit is 110kmh, you can get away with a small fine ($50) and 1 demerit point up to 119kmh - at 120kmh, it's $150 and 3 points.

If you travel at more than 45kmh an hour over the limit, your vehicle will be impounded for 28 days on the spot - you get a free ride in a police car - and the charge is "dangerous driving", that can incur a 6 mth jail term!
You will also be charged towing fees and storage fees for your impounded vehicle - and they take no responsibility for any damage whilst impounded!

As to the Sheppey crossing pileup - I have never understood why people do not slow down in fog to the available visibility distance!! It's sheer lunacy to travel at 80 or 90 kmh when you can't see more than 10 or 20 metres!

There was one incredible smash here in Australia between a truck driver with "pedal-to-the-metal" syndrome - thick fog - and an interstate freight train, weighing 4,380 tonnes!

The truck driver ploughed into the side of the second of the three locomotives on a level crossing, at around 80 kmh in thick fog.
He knocked 2 of the locomotives right off the tracks - destroyed more than 2/3rds of the freight train - and the total damage bill was over AU$30M!! It took the rescuers 5 days to find his body!

http://www.atsb.gov.au/media/24301/rair2006004_002.pdf

MG23
5th Sep 2013, 14:09
Also, every loony speed merchant thinks that he/she is the only good driver, and it's everyone else who's a loony speed merchant.

Numerous studies have shown that the safest drivers are around the 85th percentile by speed. Good drivers can and do drive fast. Bad drivers either drive faster than the safe speed because they're overconfident, or slower because they know they're bad.

In the UK, I believe speed limits used to be set based on the 85th percentile, because criminalizing the safest drivers would be insane. Now they're mostly set by politicians looking for a votes.

Speed cameras are probably also the single biggest contributor to the loss of respect for police in the UK over the last couple of decades. Criminalizing middle-class drivers who've been driving for decades without an accident because they were driving at a few miles per hour above an arbitrary speed limit is also insane.

Windy Militant
5th Sep 2013, 15:32
As to the Sheppey crossing pileup - I have never understood why people do not slow down in fog to the available visibility distance!! It's sheer lunacy to travel at 80 or 90 kmh when you can't see more than 10 or 20 metres!

Not sure of what happend there this morning but here in Oxford/Berkshire we get a lot of patchy fog by which I mean CAVOK to IFR in yards, like a wall and a lot of tailgating especially on the A34 M40, on some days you'd think the BMW autoroad train was already in use. When one of these hits a fog wall it only takes one person to hit the brakes and it all goes pear shaped.
Why I use the back roads to get to work, statistically more dangerous but feels safer.

Molemot
5th Sep 2013, 15:59
AH, MG23..the 85th percentile!! This is worth reading; science, not prejudice...

ABD - Speed Limits (http://www.abd.org.uk/topics/speed_limits.htm)

ShyTorque
5th Sep 2013, 17:17
Also, every loony speed merchant thinks that he/she is the only good driver, and it's everyone else who's a loony speed merchant.

Not only that -why are they even allowed to use my roads in the first place? ;)

ShyTorque
5th Sep 2013, 17:31
The reasons for setting speed limits?

I was always somewhat intrigued why a quarter mile of the A614, a straight stretch of road Blyth services A1, was suddenly given a 30 mph limit. It has a relatively clean accident report as far as I know (I commuted along it every day from 1988) yet the limit was suddenly reduced from the national speed limit. It appears to me that 50 mph would be perfectly safe.

Then it was pointed out to me that a number of local councillors live in the houses along that stretch. There is a transport cafe on the other side of the road. So I guess that's where they all shuffle across to in their slippers, for their all-day breakfasts.

500N
5th Sep 2013, 18:46
One Track

"To them, it's a matter of trying to reduce the road toll - as many drivers lack the necessary control skills to keep their vehicle upright and pointing in the right direction - even on a straight, flat, monotonous stretch of outback highway!"

Then why did the road toll increase when the NT brought in speed limits ?

They are now looking at or have decided to bring back unlimited on certain roads.

M.Mouse
5th Sep 2013, 20:47
Now they're mostly set by politicians looking for a votes.

So true. My road (a cul-de-sac) has by default become a 20mph zone because the road along which I travel to get to my road has had a 20mph limit imposed. I have lived here for nearly 20 years and am unaware of any accidents or injuries on that road. If you ask the local council why they imposed the limit the reply is to reduce accidents. When you ask how many accidents there have been the reply is they don't know because they don't keep statistics for each road!

20mph is pathetic and is seen as such by 99% of the people who drive along the road and totally ignore this new limit.

There is something seriously wrong with the way speed limits are currently set. On the whole I try to adhere to them but it is amazing how often I end up with a queue of cars behind me! I hasten to add I don't dither about but do drive at the limit when safe to do so.

I am also currently training for the Advanced Motorcycle Test and again adhering to the speed limits invariably leads to a queue of people behind you especially in a 30 mph zone. It doesn't bother me so much in a car but on two wheels with some muppet perched on your rear wheel when you are already travelling at the set limit for the road is as irritating as it is unnerving.

30 mph in built up areas IS plenty fast enough. I object to the blanket 40mph and 50 mph limits being set on often sparsely populated roads or even roads with no population at all.

Windy Militant
5th Sep 2013, 22:25
Yep local politics plays a big part in it. About three or four years ago a stretch of road between two villages near where I work suddenly became a thirty zone. At first it was a bit of a mystery until we discovered it was the first part of allowing that stretch of road to become eligible for development. Apparently they would not have been allowed to build there if it was a sixty zone as the access would not have been able to meet the highways requirements so they dropped the speed limit and lo and behold a couple of months ago the bulldozers moved in and began work.

ExSp33db1rd
5th Sep 2013, 22:27
20mph is pathetic and is seen as such by 99% of the people who drive along the road and totally ignore this new limit.

NZ has 20 KPH !! passing a school bus ( 12 MPH ) This gives the kids the wrong message - i.e. cars will slow down for them to run gaily across the road - but what are they going to do on their first day at work, when alighting from a public bus ?

We have a Toll Road here controlled by overhead gantry cameras - i.e. one has to pay Online before or after the jouney, or risk an added fine, no tossing coins idly into a basket. Stupid system. I once realised that I hadn't been charged, and could vaguely remember overtaking a lorry as a I passed the cameras, and assumed that I had "fallen" between two lines of sight of the cameras ? When I can, I now swerve from lane to lane as I pass under the cameras but have yet to repeat my financial success !

Tankertrashnav
5th Sep 2013, 22:28
It's not all bad news - a short stretch of single carriageway bypass (straightish, no obvious hazards) near me has just had its universally ignored 40mph speed limit upped to 50mph. I wouldnt mind betting that this will even have the affect of slowing down a few drivers, who'll be more inclined to adhere to 50 than 40.

onetrack
6th Sep 2013, 02:20
500N- The increase in road deaths in the NT since speed limits were introduced can be fairly easily explained, IMO. Statistics on a yearly basis are always misleading.
As a result, averages over several years provide a better idea. The road toll in the NT varies substantially from year to year.

Taking 6 year averages (2001-2006 and 2007 to 2012), the average annual NT road toll is 48.6 for the first period and 51.1 for the second period (after the speed limits were introduced).

This relatively small average annual increase could be sheeted home to a susbtantial increase in the number of vehicles on NT roads.
The "grey nomad" population travelling Northern Australia in Winter has exploded in recent years - with an increase in caravan production of 25% a year for the last 10 years - giving you some idea of the increase in the number of people "getting away from it all".

As one who drove North in Winter in 2012 (Perth to Darwin), after not having done so for quite a number of years, I was blown away by the absolutely vast number of caravans, motorhomes, and 4WD'ers on the Northern Hwys during that Winter drive.

The numbers on the Northern Hwys have exploded, it was almost like peak hour in the cities. So much so, there were numbers of servos who had run out of fuel - the oil companies were unable to keep up with the demand.
At one roadhouse, we waited 24 hrs for fuel supplies to arrive before we could proceed.

I'm in agreement with 130kmh limits on long isolated stetches of highway - but not unlimited speeds. The dangers of roaming livestock makes unlimited speed limits foolhardy - and the dangers to other road users pulling out onto the highway, unaware of what the speed might be of an approaching vehicle, is just unacceptable.

Can you imagine the scenario of a road train pulling out onto an unlimited speed highway? - after first checking for approaching vehicles, and seeing nothing - suddenly becoming aware of a Ferrari, M3 BMW, GTS Holden, or something similar, approaching at 250 kmh??
The dangers of the massive speed discrepancies are obvious.