They are bring in an overtaking ban, on the M11 up hill stretches.
Surely that is the wrong?

An heavily laden lorry versus a lightly loaded one, will make for a
quicker overtake on an uphill, because the heavily laden one will slow
down. On the downhill parts, the advantage is gone and all will be able
to do a similar speed.

Discuss..

On Friday, 31 March 2017 12:24:19 UTC+1, Harry Bloomfield wrote:
They are bring in an overtaking ban, on the M11 up hill stretches.
Surely that is the wrong?

An heavily laden lorry versus a lightly loaded one, will make for a
quicker overtake on an uphill, because the heavily laden one will slow
down.

I thought the idea was to stop lorries over taking each other slowing the rest of the traffic down.

On the downhill parts, the advantage is gone and all will be able
to do a similar speed.

Discuss..

On 31/03/2017 12:50, whisky-dave wrote:
On Friday, 31 March 2017 12:24:19 UTC+1, Harry Bloomfield wrote:
They are bring in an overtaking ban, on the M11 up hill stretches.
Surely that is the wrong?

An heavily laden lorry versus a lightly loaded one, will make for a
quicker overtake on an uphill, because the heavily laden one will slow
down.

I thought the idea was to stop lorries over taking each other slowing the rest of the traffic down.

On the downhill parts, the advantage is gone and all will be able
to do a similar speed.

Discuss..

If only the lorry drivers could use their common sense and only overtake
lightly loaded lorries. But two heavily laden lorries in an overtaking
situation will snarl the traffic terribly.

whisky-dave wrote :
I thought the idea was to stop lorries over taking each other slowing the
rest of the traffic down.

Yes, but only on the up hill stretches. In my opinion the is more
opportunity for lorries to overtake with a better speed differential on
the up hill stretches than on the level or the down hill parts. There
are only two lanes on the M11.

On Friday, 31 March 2017 13:06:37 UTC+1, Harry Bloomfield wrote:
whisky-dave wrote :
I thought the idea was to stop lorries over taking each other slowing the
rest of the traffic down.

Yes, but only on the up hill stretches.

That's why this new rule or law whatever it is only applies to certain sections isn't it ?

This also reminds me of the esculator idea on getting people moving 'faster' by not walking up esculators.


In my opinion the is more
opportunity for lorries to overtake with a better speed differential on
the up hill stretches than on the level or the down hill parts. There
are only two lanes on the M11.

On 31/03/2017 13:06, Harry Bloomfield wrote:
whisky-dave wrote :
I thought the idea was to stop lorries over taking each other slowing
the rest of the traffic down.

Yes, but only on the up hill stretches. In my opinion the is more
opportunity for lorries to overtake with a better speed differential on
the up hill stretches than on the level or the down hill parts. There
are only two lanes on the M11.
Aren't they usually up against the limiter anyway, unless it's a very
steep hill?

On 31/03/17 13:06, Broadback wrote:
On 31/03/2017 12:50, whisky-dave wrote:
On Friday, 31 March 2017 12:24:19 UTC+1, Harry Bloomfield wrote:
They are bring in an overtaking ban, on the M11 up hill stretches.
Surely that is the wrong?

An heavily laden lorry versus a lightly loaded one, will make for a
quicker overtake on an uphill, because the heavily laden one will slow
down.

I thought the idea was to stop lorries over taking each other slowing
the rest of the traffic down.

On the downhill parts, the advantage is gone and all will be able
to do a similar speed.

Discuss..

If only the lorry drivers could use their common sense and only overtake
lightly loaded lorries. But two heavily laden lorries in an overtaking
situation will snarl the traffic terribly.

Nothing to do with loading. All to do with speed limiters


--
Future generations will wonder in bemused amazement that the early
twenty-first centurys developed world went into hysterical panic over a
globally average temperature increase of a few tenths of a degree, and,
on the basis of gross exaggerations of highly uncertain computer
projections combined into implausible chains of inference, proceeded to
contemplate a rollback of the industrial age.

Richard Lindzen

On 31/03/17 13:37, Chris Bartram wrote:
On 31/03/2017 13:06, Harry Bloomfield wrote:
whisky-dave wrote :
I thought the idea was to stop lorries over taking each other slowing
the rest of the traffic down.

Yes, but only on the up hill stretches. In my opinion the is more
opportunity for lorries to overtake with a better speed differential on
the up hill stretches than on the level or the down hill parts. There
are only two lanes on the M11.
Aren't they usually up against the limiter anyway, unless it's a very
steep hill?

yes.


--
Future generations will wonder in bemused amazement that the early
twenty-first centurys developed world went into hysterical panic over a
globally average temperature increase of a few tenths of a degree, and,
on the basis of gross exaggerations of highly uncertain computer
projections combined into implausible chains of inference, proceeded to
contemplate a rollback of the industrial age.

Richard Lindzen

On 31/03/17 14:49, Jethro_uk wrote:
On Fri, 31 Mar 2017 13:22:35 +0000, Huge wrote:

On 2017-03-31, Broadback wrote:
[quoted text muted]

If you'd ever sat behind 2 "elephant racing" lorries for mile after mile
after mile

I have seen the entire M4/A34-M3/A34 slowed for 27 miles because of a
series of lorries playing roadblock.


"Doing the commercial two-step"


I also notice that the stretch the other way (towards the M40) *does*
have restrictions in place to prevent this behaviour. The landscape
geography is no different to the M4-M3 stretch. However David Cameron
does live there ????



--
You can get much farther with a kind word and a gun than you can with a
kind word alone.

Al Capone

"Jethro_uk" wrote in message
news
On Fri, 31 Mar 2017 13:22:35 +0000, Huge wrote:

On 2017-03-31, Broadback wrote:
[quoted text muted]

If you'd ever sat behind 2 "elephant racing" lorries for mile after mile
after mile

I have seen the entire M4/A34-M3/A34 slowed for 27 miles because of a
series of lorries playing roadblock.

I also notice that the stretch the other way (towards the M40) *does*
have restrictions in place to prevent this behaviour. The landscape
geography is no different to the M4-M3 stretch. However David Cameron
does live there ????

Yes I've been a victim of them on the A34, from M4 J13 (Newbury) to Didcot
many times. It's better now they've brought in the HGV-overtaking ban on
Gore Hill (the steep hill just south of Didcot), but it's still a problem -
mainly because so many HGVs use that route from Southampton to Birmingham.

M1 from M18 to Ferrybridge (start of 3-lane motorway rather than 2-lane
dual-carriageway) is bad too at times.

On 31/03/2017 15:26, NY wrote:
"Jethro_uk" wrote in message
news
On Fri, 31 Mar 2017 13:22:35 +0000, Huge wrote:

On 2017-03-31, Broadback wrote:
[quoted text muted]

If you'd ever sat behind 2 "elephant racing" lorries for mile after mile
after mile

I have seen the entire M4/A34-M3/A34 slowed for 27 miles because of a
series of lorries playing roadblock.

I also notice that the stretch the other way (towards the M40) *does*
have restrictions in place to prevent this behaviour. The landscape
geography is no different to the M4-M3 stretch. However David Cameron
does live there ????

Yes I've been a victim of them on the A34, from M4 J13 (Newbury) to
Didcot many times. It's better now they've brought in the HGV-overtaking
ban on Gore Hill (the steep hill just south of Didcot), but it's still a
problem - mainly because so many HGVs use that route from Southampton to
Birmingham.

M1 from M18 to Ferrybridge (start of 3-lane motorway rather than 2-lane
dual-carriageway) is bad too at times.

That's such a short section (~ 1 mile?) that it doesn't really make any
difference.

The main problem comes on level sections, where a lorry's speed is
determined by its governor, more or less regardless of the state of
loading. So when one lorry overtakes another, the closing speed is
determined by slight differences in their governor settings - and the
manoeuvre can literally go on for miles.
--
Cheers,
Roger
____________
Please reply to Newsgroup. Whilst email address is valid, it is seldom
checked.

On 31/03/2017 14:10, The Natural Philosopher wrote:
On 31/03/17 13:06, Broadback wrote:


If only the lorry drivers could use their common sense and only overtake
lightly loaded lorries. But two heavily laden lorries in an overtaking
situation will snarl the traffic terribly.

Nothing to do with loading. All to do with speed limiters


That may be true on the level. But going up hill, few lorries can reach
the speed limiter speed and their speed is determined by power to weight
ratio.
--
Cheers,
Roger
____________
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checked.

On 31/03/2017 14:11, The Natural Philosopher wrote:
On 31/03/17 13:37, Chris Bartram wrote:
On 31/03/2017 13:06, Harry Bloomfield wrote:
whisky-dave wrote :
I thought the idea was to stop lorries over taking each other slowing
the rest of the traffic down.

Yes, but only on the up hill stretches. In my opinion the is more
opportunity for lorries to overtake with a better speed differential on
the up hill stretches than on the level or the down hill parts. There
are only two lanes on the M11.
Aren't they usually up against the limiter anyway, unless it's a very
steep hill?

yes.



No. It doesn't need much of a gradient to slow them down. A heavy
lorry's drag to weight ratio and rolling resistance to weight ratio are
quite low. But add to that a component of the weight as a result of the
slope, and the required tractive effort increases dramatically.
--
Cheers,
Roger
____________
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checked.

Roger Mills formulated on Friday :
That may be true on the level. But going up hill, few lorries can reach the
speed limiter speed and their speed is determined by power to weight ratio.

Exactly, which is why the best place for over takes to take place, is
on the hill climbs rather than ban them there.

On Friday, 31 March 2017 16:04:38 UTC+1, Harry Bloomfield wrote:
Roger Mills formulated on Friday :
That may be true on the level. But going up hill, few lorries can reach the
speed limiter speed and their speed is determined by power to weight ratio.

Exactly, which is why the best place for over takes to take place, is
on the hill climbs rather than ban them there.

I though it took longer to climb hills irrespective of the type of vehicle, so why encourage it ?

In article ,
Harry Bloomfield wrote:
They are bring in an overtaking ban, on the M11 up hill stretches.
Surely that is the wrong?

An heavily laden lorry versus a lightly loaded one, will make for a
quicker overtake on an uphill, because the heavily laden one will slow
down. On the downhill parts, the advantage is gone and all will be able
to do a similar speed.

You might think that but the results of the experiments carried out on the
M11 under an experimental traffic order for 18 months starting 26March
2010 showed that by restricting lorries to the inside lane there was an
increase in traffic flow, less congestion and fewere accidents due to
frustrated car drivers. What I don't understand is why they waited 5 years
before using this knowledge!

Alan

--


Using an ARMX6

On 31/03/17 16:54, Alan Dawes wrote:
In article ,
Harry Bloomfield wrote:
They are bring in an overtaking ban, on the M11 up hill stretches.
Surely that is the wrong?

An heavily laden lorry versus a lightly loaded one, will make for a
quicker overtake on an uphill, because the heavily laden one will slow
down. On the downhill parts, the advantage is gone and all will be able
to do a similar speed.

You might think that but the results of the experiments carried out on the
M11 under an experimental traffic order for 18 months starting 26March
2010 showed that by restricting lorries to the inside lane there was an
increase in traffic flow, less congestion and fewere accidents due to
frustrated car drivers. What I don't understand is why they waited 5 years
before using this knowledge!

Alan


Sure Belgium has been doing this for years - seemed that way last time I
was there.

And yes, it was incredibly civilised - at least until the R0 ring
outside of Brussels which was slightly mad (but nothing compared to La
Peripherique around Paris which is mental).

"Roger Mills" wrote in message
...
M1 from M18 to Ferrybridge (start of 3-lane motorway rather than 2-lane
dual-carriageway) is bad too at times.

That's such a short section (~ 1 mile?) that it doesn't really make any
difference.

No, check a map. It's about 18 miles. Although *some* of the intervening
section is A1(M), which I'd forgotten about, it's still (I'm sure) only 2
lanes.

On 31/03/2017 17:48, NY wrote:
"Roger Mills" wrote in message
...
M1 from M18 to Ferrybridge (start of 3-lane motorway rather than 2-lane
dual-carriageway) is bad too at times.

That's such a short section (~ 1 mile?) that it doesn't really make
any difference.

No, check a map. It's about 18 miles. Although *some* of the intervening
section is A1(M), which I'd forgotten about, it's still (I'm sure) only
2 lanes.

Sorry - I was responding to the previous paragraph about the A34 - I
somehow missed the sentence about the M1!
--
Cheers,
Roger
____________
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checked.

"Harry Bloomfield" wrote in message
news
They are bring in an overtaking ban, on the M11 up hill stretches.

good

'bout bloody time

Surely that is the wrong?

Nope

An heavily laden lorry versus a lightly loaded one, will make for a
quicker overtake on an uphill, because the heavily laden one will slow
down. On the downhill parts, the advantage is gone and all will be able to
do a similar speed.

The lorries that are in the right hand lane clog it up so that all of the
traffic is forced to trundle along at 65 mph for mile after mile after mile

I once sat in the left hand lane all the way and timed how long it took,
compared with another trip where I sat in the right hand lane behind the
string of overtaking lorries

and from J9 (where the A10 joins) to J8 (where it goes to 3 lanes) the
difference was 90 seconds.

ISTM that a rule that lets the cars zoom past uninhibited is worth asking
the lorries to suffer an extra 90 seconds on their journey time

tim

On 31/03/2017 16:04, Harry Bloomfield wrote:
Roger Mills formulated on Friday :
That may be true on the level. But going up hill, few lorries can
reach the speed limiter speed and their speed is determined by power
to weight ratio.

Exactly, which is why the best place for over takes to take place, is on
the hill climbs rather than ban them there.

I tend to agree.
--
Cheers,
Roger
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checked.

On 31/03/2017 16:46, whisky-dave wrote:
On Friday, 31 March 2017 16:04:38 UTC+1, Harry Bloomfield wrote:
Roger Mills formulated on Friday :
That may be true on the level. But going up hill, few lorries can reach the
speed limiter speed and their speed is determined by power to weight ratio.

Exactly, which is why the best place for over takes to take place, is
on the hill climbs rather than ban them there.

I though it took longer to climb hills irrespective of the type of vehicle, so why encourage it ?

The thing which annoys car drivers is having to follow a pair of lorries
for miles on end as one overtakes the other at an infinitesimally small
closing speed. On a hill - where the speed is determined by power to
weight ratio rather speed limiters - a lightly loaded lorry will achieve
a much higher closing speed over a heavily loaded one.
--
Cheers,
Roger
____________
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checked.

On 31-Mar-17 6:05 PM, Roger Mills wrote:
On 31/03/2017 16:46, whisky-dave wrote:
On Friday, 31 March 2017 16:04:38 UTC+1, Harry Bloomfield wrote:
Roger Mills formulated on Friday :
That may be true on the level. But going up hill, few lorries can
reach the
speed limiter speed and their speed is determined by power to weight
ratio.

Exactly, which is why the best place for over takes to take place, is
on the hill climbs rather than ban them there.

I though it took longer to climb hills irrespective of the type of
vehicle, so why encourage it ?

The thing which annoys car drivers is having to follow a pair of lorries
for miles on end as one overtakes the other at an infinitesimally small
closing speed. On a hill - where the speed is determined by power to
weight ratio rather speed limiters - a lightly loaded lorry will achieve
a much higher closing speed over a heavily loaded one.

Which is fine, if only lightly loaded lorries try to overtake heavily
laden ones. In practice, if the lorry behind is doing a couple of mph
better than the one in front, it will still try to overtake.


--
--

Colin Bignell

Huge wrote:
On 2017-03-31, Tim Watts wrote:

[23 lines snipped]

And yes, it was incredibly civilised - at least until the R0 ring
outside of Brussels which was slightly mad (but nothing compared to La
Peripherique around Paris which is mental).

I used to drive regularly from Port de Bagnolet to Aulnay sous Bois
round the Peripherique and up the A1. The scariest driving experience(s)
I've ever had.



Try the Atlanta ring road in rush hour!

On Fri, 31 Mar 2017 16:09:55 -0000 (UTC), Jethro_uk
wrote:



I have a vague memory that there was an earlier experiment on the M42
past the NEC/M6 junction.

There's still a short section on the A42 section Northbound just
before Ashby. Works well until the lorries are allowed to overtake
again.

--
AnthonyL

On 31/03/2017 17:57, Roger Mills wrote:
On 31/03/2017 16:04, Harry Bloomfield wrote:
Roger Mills formulated on Friday :
That may be true on the level. But going up hill, few lorries can
reach the speed limiter speed and their speed is determined by power
to weight ratio.

Exactly, which is why the best place for over takes to take place, is on
the hill climbs rather than ban them there.

I tend to agree.

Have you considered just how much time it will save them?

They overtake one or two lorries and then join the queue after five or
six hills they may be 500 yards in front so about 45 seconds.

Whereas the car the held up could be ten minutes or more in front.

It isn't worth them overtaking, they just don't understand.

whisky-dave wrote :
I though it took longer to climb hills irrespective of the type of vehicle,
so why encourage it ?

My car would hardley notice a hill, even when towing. Heavily loaded
HGV's do slow down due to inclines.

On 31/03/2017 17:56, tim... wrote:

An heavily laden lorry versus a lightly loaded one, will make for a
quicker overtake on an uphill, because the heavily laden one will slow
down. On the downhill parts, the advantage is gone and all will be
able to do a similar speed.

The lorries that are in the right hand lane clog it up so that all of
the traffic is forced to trundle along at 65 mph for mile after mile
after mile

You're lucky that they are speeding.

AnthonyL wrote:

There's still a short section on the A42 section Northbound just
before Ashby. Works well until the lorries are allowed to overtake
again.

Also the western end of the A14, but only certain times of day

On 31/03/2017 14:22, Huge wrote:
On 2017-03-31, Broadback wrote:
On 31/03/2017 12:50, whisky-dave wrote:
On Friday, 31 March 2017 12:24:19 UTC+1, Harry Bloomfield wrote:
They are bring in an overtaking ban, on the M11 up hill stretches.
Surely that is the wrong?

An heavily laden lorry versus a lightly loaded one, will make for a
quicker overtake on an uphill, because the heavily laden one will slow
down.

I thought the idea was to stop lorries over taking each other slowing the rest of the traffic down.

On the downhill parts, the advantage is gone and all will be able
to do a similar speed.

Discuss..

If only the lorry drivers could use their common sense and only overtake
lightly loaded lorries. But two heavily laden lorries in an overtaking
situation will snarl the traffic terribly.

If you'd ever sat behind 2 "elephant racing" lorries for mile after mile
after mile, you'd think it was a good idea, as I do.



The correct name for the drivers of such vehicles are knob jockeys.



--
Adam

On 31/03/2017 15:26, NY wrote:

M1 from M18 to Ferrybridge (start of 3-lane motorway rather than 2-lane
dual-carriageway) is bad too at times.

You are correct

I am sure you meant A1 not M1 and some of that section it just good old
fashioned A1 and not A1(M).

Those bad times you mentioned (Northbound) are every Monday to Friday
from 7am to 9am:-)

I can get to Ferrybridge (I work there quite often) faster from
Doncaster via the A630 the M18 and M62.






--
Adam

On 31/03/2017 20:27, Andy Burns wrote:
AnthonyL wrote:

There's still a short section on the A42 section Northbound just
before Ashby. Works well until the lorries are allowed to overtake
again.

Also the western end of the A14, but only certain times of day


What happened to the caravans must keep to left hand lane on the M5?

Just after Gordano services ISTR.

--
Adam

On 31/03/17 17:32, Huge wrote:
On 2017-03-31, Tim Watts wrote:

[23 lines snipped]

And yes, it was incredibly civilised - at least until the R0 ring
outside of Brussels which was slightly mad (but nothing compared to La
Peripherique around Paris which is mental).

I used to drive regularly from Port de Bagnolet to Aulnay sous Bois
round the Peripherique and up the A1. The scariest driving experience(s)
I've ever had.

Scary yes, but not as scary as A7/A12 around Genova.



--
djc

(–€Ì¿Ä¹Ì¯–€Ì¿ Ì¿)
No low-hanging fruit, just a lot of small berries up a tall tree.

On 3/31/2017 5:32 PM, Huge wrote:
On 2017-03-31, Tim Watts wrote:

[23 lines snipped]

And yes, it was incredibly civilised - at least until the R0 ring
outside of Brussels which was slightly mad (but nothing compared to La
Peripherique around Paris which is mental).

I used to drive regularly from Port de Bagnolet to Aulnay sous Bois
round the Peripherique and up the A1. The scariest driving experience(s)
I've ever had.


Brussels ring road, 70's, lane 3 of four on an embankment without a
crash barrier, a wagon in lane 2 flipped a metal structure into my lane
giving me a fast front puncture on cross-plies (and a slow rear
puncture, as it turned out). That was fun for a moment.

On Fri, 31 Mar 2017 15:51:29 +0100, Roger Mills wrote:

No. It doesn't need much of a gradient to slow them down. A heavy
lorry's drag to weight ratio and rolling resistance to weight ratio are
quite low. But add to that a component of the weight as a result of the
slope, and the required tractive effort increases dramatically.

20, 30 years ago you'd often come across a lorry doing 30 or 40 mph
up a motorway "hill". These days the vast majority of trucks have
enough power to maintain their speed on the relatively gentle
inclines found on motorways.

The major problem is the slight differences in the calibration of the
limiters (*) meaning a truck attempts to overtake with only 1/4 mph
speed advantage. Happens on the flat, not just hills, thinking of the
dual carriage way parts of the A1 south of Newcastle and the M6 south
of Lancaster.

(*) I have sneaky feeling that modern "limiters" are really rather
sophisticated cruise controls that also have control of the brakes.
Often see a truck trundling down a hill at an apparent steady speed
but it'll briefly brake, maybe only once or twice but well before a
human would notice and far shorter.

--
Cheers
Dave.

They had that on the A20 coming out of Dover but as there are no police to enforce it the drivers just ignored it and sat beside each other going up the hill.

On Fri, 31 Mar 2017 18:23:17 +0100, Nightjar
wrote:

On 31-Mar-17 6:05 PM, Roger Mills wrote:
On 31/03/2017 16:46, whisky-dave wrote:
On Friday, 31 March 2017 16:04:38 UTC+1, Harry Bloomfield wrote:
Roger Mills formulated on Friday :
That may be true on the level. But going up hill, few lorries can
reach the
speed limiter speed and their speed is determined by power to weight
ratio.

Exactly, which is why the best place for over takes to take place, is
on the hill climbs rather than ban them there.

I though it took longer to climb hills irrespective of the type of
vehicle, so why encourage it ?

The thing which annoys car drivers is having to follow a pair of lorries
for miles on end as one overtakes the other at an infinitesimally small
closing speed. On a hill - where the speed is determined by power to
weight ratio rather speed limiters - a lightly loaded lorry will achieve
a much higher closing speed over a heavily loaded one.

Which is fine, if only lightly loaded lorries try to overtake heavily
laden ones. In practice, if the lorry behind is doing a couple of mph
better than the one in front, it will still try to overtake.

Is the right answer / reason.

It seems that if they have their foot on the floor and they are
closing on a vehicle they (probably a selfish minority) *have* to
overtake, even if it is going to take 5 miles.

But once again, because of what I believe is a selfish minority, we /
they all get hit by the same ban.

However, I can also appreciate (mainly as a cyclist / motorcyclist)
that there can be occasions when you feel you are making good speed on
someone, go to overtake then find the headwind suddenly takes away any
hope you had and you lose maybe half of the advantage. I'm not sure
how much impact headwind has on a lorry but knowing they are worse
aerodynamically than cyclists or even motorcycles then it could be
'quite a lot'.

The other things is I wonder how much of this isn't helped by the
lorry being overtaken speeding up (because it happens they can because
of a gradient change or shift in wind direction) and then leaving the
overtaking vehicle stranded? If so I thought that was against the
rules / highway code (even if only by 5mph)?

Cheers, T i m

T i m wrote:

It seems that if they have their foot on the floor and they are
closing on a vehicle they (probably a selfish minority) *have* to
overtake, even if it is going to take 5 miles.

Presumably it's far easier to plant your boot on the accelerator and let
the speed limiter kick-in, than to manually match your speed/distance to
the truck in front.

What if there was a fine-grained tuning knob on the speed limiter, so
they could trim it *down* by a fraction of a mph and keep up with the
vehicle in front without the bother of having to do it manually, or a
radar based distance-keeper like some cars have?

On Sat, 1 Apr 2017 10:17:55 +0100, Andy Burns
wrote:

T i m wrote:

It seems that if they have their foot on the floor and they are
closing on a vehicle they (probably a selfish minority) *have* to
overtake, even if it is going to take 5 miles.

Presumably it's far easier to plant your boot on the accelerator and let
the speed limiter kick-in, than to manually match your speed/distance to
the truck in front.

I guess, especially if the difference in speeds is marginal.

What if there was a fine-grained tuning knob on the speed limiter, so
they could trim it *down* by a fraction of a mph and keep up with the
vehicle in front without the bother of having to do it manually, or a
radar based distance-keeper like some cars have?

Either might work (and the latter probably work better) and is in fact
what I though those who were envisioning what our roads would be like
in the future predicted? That is, 'trains' of vehicles all going along
together automatically?

There is nothing more frustrating that allowing a big truck out (often
more like back off to stop it hitting you as they swerve out at the
last moment) and then having (along with 40 other cars and faster
vehicles) then sit behind it and what it is overtaking for the next 5
miles.

Maybe being a 'Knight of the road' goes out of the window when you are
on a deadline?

I often tow (behind the car, motorbike and cycle) and am very aware
that I, often because of the law rather than any physical / speed
limitations of my vehicles, are forced to go slower that the road
would typically allow. So, I am very conscious of what is behind me
and will very often (as soon as the circumstances allow or make it so
asap if not) either pull over / slow on an obvious / clear overtaking
spot (indicating left as I do so) or pull into a lay by or petrol
station just long enough to let anyone past.

I have observed some slow farm vehicles doing the same and many more
that do not.

Cheers, T i m

"T i m" wrote in message
...
Either might work (and the latter probably work better) and is in fact
what I though those who were envisioning what our roads would be like
in the future predicted? That is, 'trains' of vehicles all going along
together automatically?

The problem with a "train" of lorries all going along at exactly the same
speed is that they may follow at a barely-safe distance from each other -
certainly too small a distance for a car to nip between them. So when you
come to one of these "trains" you know that you have to find an opportunity
to overtake *all* of them in one go, because you won't be able to get past
them individually, in stages.

On a motorway or dual carriageway, that's fine: the only traffic you need to
worry about is what is coming up behind you. But "trains" wouldn't be
workable on a single-lane road because you'd never find a time when you
could get past a "train" of maybe 10 lorries without a car coming in the
opposite direction while you were on the wrong side of the road.

On a single-carriageway road, good lorry drivers (and there *are* some!)
keep a sensible gap from another lorry to give cars that want to go faster
than them the opportunity to leapfrog past lorries one by one.