Stopping Distances. realistic ??

[M@H]

What do people think about actual stopping distances vs Highway code..?

The code says:

20 MPH
6 metres thinking 6 metres stopping = 12 metres (40 feet) or 3 car lengths

30 MPH
9 metres thinking 14 metres stopping = 23 metres (75 feet) or 6 car lengths

40 MPH
12 metres thinking 24 metres stopping = 36 metres (120 feet) or 9 car lengths

50 MPH
15 metres thinking 38 metres stopping = 53 metres (175 feet) or 13 car lengths

60 MPH
18 metres thinking 55 metres stopping = 73 metres (240 feet) or 18 car lengths

70 MPH
21 metres thinking 75 metres stopping = 96 metres (315 feet) or 24 car lengths

But this must be out of date by now with advances in motor car manufacture..??? or is it ???

[plotloss]

The 911 Turbo (993 I think) as tested by Clarkson will do 70-0 in just over 80ft.

However, the law needs to cater for the lowest common denominator and seeing some of the driving I have this weekend 315ft seems about 3 miles too short.

Matt.

[smeagol]

I had this discussion with my IAM instructor as you're supposed to quote these and stick to the distance on your driving. Trust me its a stupid distance at all speeds except if you're driving an SUV, or ford Anglia. In fact I'm sure that the Chevrons painted on Motorways aren't 96metres/ 315 feet apart which are supposed to keep you at a safe distance.

>> Edited by smeagol on Tuesday 2nd April 14:32

[s2 giles]

The distances have been wrong for some time, any plonker can break even in a 15 year old escort with less distance than these.

What annoys me more is the advert on TV about a Nissan Sunny Saloon that crashes into a pedestrian (child just to tug the heart strings)supposedly using the distances suggested above.....with its wheels locked and smoking of course. In reality the car would stop alot quicker than these distances, even if skidding ! and the child wouldnt of been touched.

Its all about spin you know

[Terminator]

quote:In fact I'm sure that the Chevrons painted on Motorways aren't 96metres/ 315 feet apart which are supposed to keep you at a safe distance.

You're correct, they're not. Assuming that the vehicle on front of you is travelling around the same speed as you are, it's stopping distance will be roughly the same too. The distance between the chevrons should allow for your reaction time and your stopping distance relative to his (assuming his brake lights work!)

[adeewuff]

If I remember correctly the distances quoted by the highway code were adopted just after WW2!! So yes it could be said that they are a little bit out of date.

I can't remember which Car TV program I saw it on but they did a comparison with several cars seeing just how short the stopping distances are now. I think at the 70 mph run they stopped in half the distance quoted in the highway code.

>> Edited by adeewuff on Tuesday 2nd April 15:01

[marki]

i saw on i think top gear some years back a braking comparison filmed in car between a car and an hgv done side by side on a track , basicaly the truck did not even seem to slow and just ploughed on out of camera shot , scary stuff when you think of the truck stuck up you butt on a full motorway moving at 55-60 mph

[mondeoman]

Check the advert again - its only one set of wheels that r locked (rears I think), so its probable that its not on full braking (I know, I know, if they were locked it'd take longer to stop cos of the reduced coefficient of friction). On the other hand, why doesn't he stear into the parked cars?? or is a car more valuable than a child?? A point to ponder on perhaps.........

[s2ooz]

exellent point, he should have been taught to pass his test, therefore this teaching requires you to know how to get out of a locked wheel situation and how to steer while braking. clearly this advert shows poor driving, not speeding being at fault..

as for stopping distances, you have to cater for all cars in the argument, and ford anglias are not a banned vehicle.

[CarZee]

quote:as for stopping distances, you have to cater for all cars in the argument, and ford anglias are not a banned vehicle.

Hmm.. Lowest Common Denominator safety legislation is here in plain view for us to see how cretinous it is..

Fail the Anglias/Moggys of the world on their MOT tests until retrofitted with a proper braking system and radial tyres - that problem soon goes away...

[smeagol]

quote:
as for stopping distances, you have to cater for all cars in the argument, and ford anglias are not a banned vehicle.

Actually the highway code says these are typical stopping distances not the maximum. In others words these should be for the average car (as when they were written for the Ford Anglia). It actually states that lerge vehicels and motorcycles need a bigger distance to stop. (there's not many motorcycles I could name that take over 96metres to stop from 70)

[M@H]

Just worked out that the thinking time assigned to the figures equates to about 0.7 of a second... so respond any slower than that and you are not typical of the people at the DVLA...

..and what happens to reaction times as you get older ...??

Cheers
Matt..

[hertsbiker]

THAT bloody advert again... have we any proof it was doing 35, not 55, to make it look bad? or the engine is being used to "drag" the back tyres?

Lies, damn lies, and statistics !


C

[reardrive]

Whether the distances are realistic or not it's impossible to judge to within a metre how close you are - even if you can memorise them for whatever speed you're doing.
To me the 'two second rule' is far easier to apply, it's a simple formula that works at all speeds: Take a fixed point (e.g. lamp-post), when the car in front passes say 'only a fool breaks the two second rule' and you should pass the reference point after that. The higher the speed, the bigger the gap and it always seems a comfortable distance to me.
However, leave a gap that size on an urban m/way and three cars will pull into it.

[Graham]

if i remember correctly clarkson re produced that test, even the anglia stopped in the distance from 70 ft... even if it did wag about abit...

the dicovery did it with no trouble and the porker ( and the pug 106) did it in about 10 ft

[steve harrison]

If we're talking "lowest common denominator" the Highway Code unfortunately omits:

Taking eyes of the girl on the pavement's tits distance 375ft

Taking eyes off the girl in the passenger seat's tits distance 550ft

Adjusting sub-woofer for maximum resident irritation disance 1200ft

Stopping screaming at the kids and looking forward distance 1550ft

Getting ancient eyes to focus distance 250ft

Looking for humbugs in glovebox distance 2000 ft

Typing text message into phone distance 3500ft

Checking hair in mirror distance 2300ft

Finish applying lippie distance 17mile

Kind of makes how good your brakes are pretty irrelevant if you're NOT LOOKING WHERE YOU'RE GOING f***wit.

[JonRB]

quote:the dicovery did it with no trouble

On the contrary, I seem to remember that the Disco actually required the full stopping distance. JC then went on to say that although many cars (the Porsche and, surprisingly, the little Pug 106) could stop in half the distance or less, lumbering 2-tonne lumps of metal with poor brakes like the Discovery still needed the same stopping distance as a Ford Anglia.
Well there's progress for you.

[XPLOD]

A point well made Steve. I must have dealt with countless RTA's over the years and I don't recall a single one being a result of inadequate brakes. It is usually down to inadequate driving: not being able to stop in the distance you can see to be clear. Poor hazard perception and planning etc... Car in gear, brain in neutral.

[Bob the Planner]

quote:
Car in gear, brain in neutral.

How often do we see this ! Best quote in quite a while - well made me giggle anyway.