Chris Tolley (ukonline really) gurgled happily,
sounding much like they were saying:

Since the 1960s car control has improved tremendously from power
steering through ABS brakes, yet the Highway Code still has the
stopping (thinking/braking) distances of old. I would like to see
these distances recast for modern cars with two tables, one for dry
conditions and one for wet.

The tables will continue to be current until all non-"modern" vehicles
are removed from the roads.

Even though the vehicles to which they are relevant are a _tiny_ minority
of those on the roads - and they are wildly optimistic for other vehicles?

Adrian wrote:

Chris Tolley (ukonline really) gurgled happily,
sounding much like they were saying:

Since the 1960s car control has improved tremendously from power
steering through ABS brakes, yet the Highway Code still has the
stopping (thinking/braking) distances of old. I would like to see
these distances recast for modern cars with two tables, one for dry
conditions and one for wet.

The tables will continue to be current until all non-"modern" vehicles
are removed from the roads.

Even though the vehicles to which they are relevant are a _tiny_ minority
of those on the roads - and they are wildly optimistic for other vehicles?

This may come as a shock to you, but the tables never had anything to do
with real performance. They are a simple mathematical model linking the
speed in mph with the stopping distance in feet. Anyone with GCSE maths
should take no more than 2 minutes to deduce the formula that is used..

--
http://gallery120232.fotopic.net/p14486552.html
(47 009 at Stratford Depot, 4 Jul 1981)

Chris Tolley (ukonline really) gurgled happily,
sounding much like they were saying:

Since the 1960s car control has improved tremendously from power
steering through ABS brakes, yet the Highway Code still has the
stopping (thinking/braking) distances of old. I would like to see
these distances recast for modern cars with two tables, one for dry
conditions and one for wet.

The tables will continue to be current until all non-"modern" vehicles
are removed from the roads.

Even though the vehicles to which they are relevant are a _tiny_
minority of those on the roads - and they are wildly optimistic for
other vehicles?

This may come as a shock to you, but the tables never had anything to do
with real performance. They are a simple mathematical model linking the
speed in mph with the stopping distance in feet. Anyone with GCSE maths
should take no more than 2 minutes to deduce the formula that is used..

Sure. But the formula was based on a roughly representative family car of
the period - the 105E Anglia, allegedly.

On Thu, 29 Jul 2010 23:28:59 +0100, Neil Williams
wrote:
On Thu, 29 Jul 2010 14:08:34 +0100, Paul Terry
wrote:

Added to which, it has been widely reported (and confirmed by the
cameras' manufacturer) that drivers can defeat a SPECS camera by the
potentially unsafe practice of lane-hopping during the measured section
of road.

Really? I always assumed that either of the two cameras would work.
(Not sure why it's 2 - if it's lane based there should logically be 3
across a motorway).


There are only ever two on the cantilever posts. However, if they are
mounted on an overhead gantry, you can have as many as you like.

I have done some work for a firm that supplies these cameras, and it
is true that lane hopping can defeat them (although I wouldn't bet my
licence on it!). But a new generation of control system is being
trialled which allows number plate recognition data from all lanes to
be used. I couldn't find out where it was being trialled, but I
strongly suspect (from where the firm is located) that it would be on
M1 Junction 10-13.

Of course the easiest way to 'defeat' the cameras is to stick to the
speed limit. Boring, I know, but it also helps save fuel.

On Fri, 30 Jul 2010 11:05:56 +0100
Bruce wrote:
Of course the easiest way to 'defeat' the cameras is to stick to the
speed limit. Boring, I know, but it also helps save fuel.

Actually the easiest way to defeat them is to drive a foreign registered
car of which there are plenty around. If road safety was really the concern
then they'd have traffic plods patrolling the road, not revenue raising
"safety" cameras.

B2003

Adrian wrote:

Chris Tolley (ukonline really) gurgled happily,
sounding much like they were saying:

Since the 1960s car control has improved tremendously from power
steering through ABS brakes, yet the Highway Code still has the
stopping (thinking/braking) distances of old. I would like to see
these distances recast for modern cars with two tables, one for dry
conditions and one for wet.

The tables will continue to be current until all non-"modern" vehicles
are removed from the roads.

Even though the vehicles to which they are relevant are a _tiny_
minority of those on the roads - and they are wildly optimistic for
other vehicles?

This may come as a shock to you, but the tables never had anything to do
with real performance. They are a simple mathematical model linking the
speed in mph with the stopping distance in feet. Anyone with GCSE maths
should take no more than 2 minutes to deduce the formula that is used..

Sure. But the formula was based on a roughly representative family car of
the period - the 105E Anglia, allegedly.

The formula is far too simple to be based on anything real. It no doubt
gives and always gave a safety margin. But until every relevant vehicle
has ABS and other suitable gizmos, revising the table only serves to
create a misleading impression of safety. The poster I was responding to
initially clearly has a sufficiently misleading impression of his own
abilities already.


--
http://gallery120232.fotopic.net/p9683800.html
(153 330 at Cark and Cartmel, Jul 1995)

Chris Tolley (ukonline really) gurgled happily,
sounding much like they were saying:

Since the 1960s car control has improved tremendously from power
steering through ABS brakes, yet the Highway Code still has the
stopping (thinking/braking) distances of old. I would like to see
these distances recast for modern cars with two tables, one for dry
conditions and one for wet.

The tables will continue to be current until all non-"modern"
vehicles are removed from the roads.

Even though the vehicles to which they are relevant are a _tiny_
minority of those on the roads - and they are wildly optimistic for
other vehicles?

This may come as a shock to you, but the tables never had anything to
do with real performance. They are a simple mathematical model linking
the speed in mph with the stopping distance in feet. Anyone with GCSE
maths should take no more than 2 minutes to deduce the formula that is
used..

Sure. But the formula was based on a roughly representative family car
of the period - the 105E Anglia, allegedly.

The formula is far too simple to be based on anything real.

No, but the formula would have been worked so that the resulting stopping
distances are approximately correct for "something real".

It no doubt gives and always gave a safety margin. But until every
relevant vehicle has ABS

Which doesn't actually make the slightest difference to stopping
distances, since it does absolutely nothing at all unless the driver
cocks up in a way that would have failed them their driving test.

and other suitable gizmos

You seem to miss the subtle detail that the distances are massively long
for any even remotely competent and roadworthy vaguely modern vehicle.

Adrian wrote:

Chris Tolley (ukonline really) gurgled happily,
sounding much like they were saying:

Since the 1960s car control has improved tremendously from power
steering through ABS brakes, yet the Highway Code still has the
stopping (thinking/braking) distances of old. I would like to see
these distances recast for modern cars with two tables, one for dry
conditions and one for wet.

The tables will continue to be current until all non-"modern"
vehicles are removed from the roads.

Even though the vehicles to which they are relevant are a _tiny_
minority of those on the roads - and they are wildly optimistic for
other vehicles?

This may come as a shock to you, but the tables never had anything to
do with real performance. They are a simple mathematical model linking
the speed in mph with the stopping distance in feet. Anyone with GCSE
maths should take no more than 2 minutes to deduce the formula that is
used..

Sure. But the formula was based on a roughly representative family car
of the period - the 105E Anglia, allegedly.

The formula is far too simple to be based on anything real.

No, but the formula would have been worked so that the resulting stopping
distances are approximately correct for "something real".

Perhaps you should offer some evidence for this contention.

Put it this way - I didn't bother to memorise the distances for my
driving test. I memorised the formula, and as I say, it links mph to
feet. The only way in which it would have any resemblance to reality is
if there were some universal driving constant whose value happens to lie
in the region of 1/5280, being the conversion factor from miles to feet.

It no doubt gives and always gave a safety margin. But until every
relevant vehicle has ABS

Which doesn't actually make the slightest difference to stopping
distances, since it does absolutely nothing at all unless the driver
cocks up in a way that would have failed them their driving test.

Never having had a car so fitted, I wouldn't know. The only evidence I
have to go by is that the continuous rubber smears on the road tend to
be longer than that dashed ones, from which I infer that ABS reduces
stopping distances.

and other suitable gizmos

You seem to miss the subtle detail that the distances are massively long
for any even remotely competent and roadworthy vaguely modern vehicle.

You seem to miss the subtle detail that I have said repeatedly that the
distances are a mathematical enterprise, nothing to do with reality and
include a safety margin.

Personally, I drive according to the two second rule. That's much more
straightforward. I observe that many of my fellow road users think they
are considerably better drivers and can get away with a 0.5 second rule.

--
http://gallery120232.fotopic.net/p10589947.html
(37 092 at London Liverpool Street, 13 Apr 1980)

On 30 July, 11:23, Adrian wrote:
Chris *Tolley (ukonline really) gurgled happily,
sounding much like they were saying:





Since the 1960s car control has improved tremendously from power
steering through ABS brakes, yet the Highway Code still has the
stopping (thinking/braking) distances of old. *I would like to see
these distances recast for modern cars with two tables, one for dry
conditions and one for wet.
The tables will continue to be current until all non-"modern"
vehicles are removed from the roads.
Even though the vehicles to which they are relevant are a _tiny_
minority of those on the roads - and they are wildly optimistic for
other vehicles?
This may come as a shock to you, but the tables never had anything to
do with real performance. They are a simple mathematical model linking
the speed in mph with the stopping distance in feet. Anyone with GCSE
maths should take no more than 2 minutes to deduce the formula that is
used..
Sure. But the formula was based on a roughly representative family car
of the period - the 105E Anglia, allegedly.
The formula is far too simple to be based on anything real.

No, but the formula would have been worked so that the resulting stopping
distances are approximately correct for "something real".

It no doubt gives and always gave a safety margin. But until every
relevant vehicle has ABS

Which doesn't actually make the slightest difference to stopping
distances, since it does absolutely nothing at all unless the driver
cocks up in a way that would have failed them their driving test.

and other suitable gizmos

You seem to miss the subtle detail that the distances are massively long
for any even remotely competent and roadworthy vaguely modern vehicle.

I don't think that they're massively long. If you look at the table in
the highway code, it gives the distances in terms of car lengths
(being 4m):

20mph = 3 car lengths, 50mph = 13 car lengths, 70mph = 24 car lengths
(=96m) with the other speeds in between.

These numbers seem about right to me, maybe slightly over at lower
speeds but not massively.

Chris Tolley (ukonline really) gurgled happily,
sounding much like they were saying:

This may come as a shock to you, but the tables never had anything
to do with real performance. They are a simple mathematical model
linking the speed in mph with the stopping distance in feet. Anyone
with GCSE maths should take no more than 2 minutes to deduce the
formula that is used..

Sure. But the formula was based on a roughly representative family
car of the period - the 105E Anglia, allegedly.

The formula is far too simple to be based on anything real.

No, but the formula would have been worked so that the resulting
stopping distances are approximately correct for "something real".

Perhaps you should offer some evidence for this contention.

Put it this way - I didn't bother to memorise the distances for my
driving test. I memorised the formula, and as I say, it links mph to
feet. The only way in which it would have any resemblance to reality is
if there were some universal driving constant whose value happens to lie
in the region of 1/5280, being the conversion factor from miles to feet.

So did this formula get plucked from thin air for a totally random result?

Why 75m from 70mph?
Why not 200m or 20m?

It no doubt gives and always gave a safety margin. But until every
relevant vehicle has ABS

Which doesn't actually make the slightest difference to stopping
distances, since it does absolutely nothing at all unless the driver
cocks up in a way that would have failed them their driving test.

Never having had a car so fitted, I wouldn't know. The only evidence I
have to go by is that the continuous rubber smears on the road tend to
be longer than that dashed ones, from which I infer that ABS reduces
stopping distances.

Did you miss the "unless"?

Personally, I drive according to the two second rule. That's much more
straightforward. I observe that many of my fellow road users think they
are considerably better drivers and can get away with a 0.5 second rule.

I don't think anybody's said anything to contradict that.

But if these figures purport to be a typical "stopping distance", do you
not think it might actually be useful if they were?