Just out of interest for maybe the chaps that run their own vehicles, is 40 less efficient for fuel burn vs 50?
I guess an 80 mph closing speed vs 100 mph closing speed may have similar outcomes in a head on with all the energy to dissipate in a long heavy object with relatively small frontal area and cabs forming the only crumple zones. If you fell off the road or hit a tree then like you say 40 would be much safer.
LIBERTY_GUY:
macplaxton:
“We are analysing your feedback”That means it’s gathering dust at the minute in the in tray.
Thanks for the update Mac.
There is no doubt that the brakes and handling on trucks are far better than they were many years ago, so it would certainly be a worthwhile introduction.
I agree, truck brakes and handling have improved over the years, but drivers haven’t, their seems to be a breed of driver out there that would make an increase from 40 mph dangereous, evidence of that can be seen on a daily basis on a road near you! the M6 this last week between jnt 5 and 6 twice springs to mind.
weeto:
I agree, truck brakes and handling have improved over the years, but drivers haven’t, their seems to be a breed of driver out there that would make an increase from 40 mph dangerous, evidence of that can be seen on a daily basis on a road near you!
There are undoubtedly good drivers and bad drivers even amongst hgv and psv license holders. Some even manage to wreak havoc at less than 5mph in yards and loading areas on a daily basis, all over the country.
Thing is though, at one time police used to ignore lorries travelling at 50mph and preventing a rolling road block at lower speeds. Then attitudes changed and speed cameras that differentiated between trucks and other vehicles started to appear on some routes, all as part of the bigger money making scam that is ‘safety’ cameras.
Last week you could see lorries driving legally at 56mph on the motorways, including through thick banks of fog where visibility was very poor and they would be unable to stop. The lorries only bumps that occurred on the M6 by Birmingham, were as a result of people not leaving separation distances and not watching what was happening up ahead. Bad driving and poor observation wrote off those trucks rather than excessive speed.
I say keep it at 40mph, if only from a selfish point of view being on hourly pay.
An increase would only encourage some “planners” 
, to reduce time schedules that are already too tight.
Also say it was increased to 50, you would only get many sat on the limiter all day on A roads anyway, and if anybody comes back with “Well what’s wrong with that” maybe they should question if they are fit to be in charge of 44 tonnes out on their own.
Drift,
There will be a ‘speed sweet spot’ for any vehicle where fuel consumption per mile is lowest. Speed too low is simply where the mechanical advantage of the engine is being wasted and it is working too hard but not really getting anywhere. But speed too high, parasitic drag increases exponentially as the square of the speed, so there will be a point where the faster you go, the more fuel you use per unit distance. In physics terms, the point of best efficiency (best gas mileage), will be the lowest point of a curve on a ‘power required’ vs ‘speed’ graph, which some smartass from Europe determined should be an average of 90 kph for HGVs 
And while I can’t understand motorway/dual carriageway speeds remaining static for over half a century, I can understand HGV single carriageway speed limits remaining the same; a 44 tonne mass at 40 MPH smashing into a car at 60 MPH still has the same kinetic energy now as it did 50 years ago, and with no central reservation separating the opposing traffic flows, it doesn’t matter how good your brakes are if another vehicle (or you) suddenly veers across the white lines.
Javiatrix:
it doesn’t matter how good your brakes are if another vehicle (or you) suddenly veers across the white lines.
Exactly.
Another thing to consider, apart from increased carnage when the inevitable happens and reduced pricing due to the job being done faster is the 48 hour average working week. WTF has that got to do with anything I hear you say. Well, if doing 50 on singles saves you just 10 minutes per day that’s 50 minutes per week. Over a 17 week reference period it’s over 14 hours. If your salary paid and your boss likes to sail you as close to the 48 hour limit as he dares he’ll just lump all that saved time on you in other ways so you’re increasing your workload with no benefit to yourself. If you’re hourly paid you’re reducing your pay.
I’ve tried to drill this into my old man but I might as well talk to the wall. He blasts down the A14 to Felixstowe and back at 56. Now if he stuck to 50 it would take him 17 mins longer each way so 34 minutes per trip. And he goes a couple of times per week. Some times he’ll do a run and when he gets back they say, “oh, can you just drop a unit off at Hartshornes before you go”. This annoys him. I’ve tried telling him that if he kept to the limit on the A14 he wouldn’t have time for these things but, in one ear and out the other.
It primarily seems to be the logistics and freight industry that is pushing for this increase up from the current 40mph limit and keeping on open mind on the issue, I can see why on paper at least it would bring benefits to them, albeit marginal in the real world outside of the traffic planner’s office.
The safety side is certainly an important consideration, but it it whether the marginally increased risk is offset by improved traffic flow on major routes and whether it brings any worthwhile financial benefits to the haulage industry?
Not quite sure why hauliers get themselves into contracts where the margins are so tight, they would just be better leaving their money in the building society. 
The road network is the one work environment that none of us have any control over. Just one bump, or one diversion puts the best laid plans in turmoil…
LIBERTY_GUY:
I take no chances nowadays and stick rigidly to all the limits
Well you must be the only one who does.
Well i think it should be 60 for trucks and 40 for cars.
See how they like it. 
puntabrava:
LIBERTY_GUY:
I take no chances nowadays and stick rigidly to all the limitsWell you must be the only one who does.
I have four licenses to protect. Car, motorbike, HGV and PSV…
Can never understand professional drivers risking their livelehoods for some ‘Thora Hird’ in a transport office. 
puntabrava:
LIBERTY_GUY:
I take no chances nowadays and stick rigidly to all the limitsWell you must be the only one who does.
Nope, I’m with Liberty Guy on this. I stick rigidly to 40 on SCs and 50 on DC A roads. Why rush? It’s not me that benefits from rushing, though it will most certainly be my licence that suffers if I get zapped.
Apart from anything else it’s often not safe to go much more that 40 on a winding SC road with a fully freighted decker. If the limits were raised, all that would happen is more lorry drivers would end up stuck behind those of us who were driving at a safe speed for the road. Just because the limit’s higher doesn’t mean it’s suddenly safe to drive at it.
Next time you sit religiously at 40mph on a decent enough A road check your mirrors and then ask yourselves why there is a reasonable argument for upping the limit to 50.
ajt:
Next time you sit religiously at 40mph on a decent enough A road check your mirrors and then ask yourselves why there is a reasonable argument for upping the limit to 50.
There’s never much behind me, as I regularly pull over to let everyone past. The fact that there’s traffic behind, however, doesn’t automatically mean that it’s safe to drive faster …
