Safe Speed Forums

From the Sunday Mail, 12th December 2004:

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Paul Smith
Our scrap speed cameras petition got over 28,000 sigs
The Safe Speed campaign demands a return to intelligent road safety

Since he's only a PC I suspect he's in the warm'n'smelly. If he was an ACC or something it'd be a smack on the wrist.

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Make everything as simple as possible, but not simpler - Einstein

LTI20/20? I think someone needs a trip over to Pepipoo.

Another one for the Safe Speed hall of fame..


BTW as a foot note on the rest of the feature it does not take 1000ft to stop from 120mph in a modern car, but then if they are still working in imperial units they probably assume we still have drum brakes.

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Speed camera policy Kills

Absolutely. In an Impreza or an M3 we could reasonable expect to stop from 150mph in under 1000 feet. (but I think that's what the Police said)

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Paul Smith
Our scrap speed cameras petition got over 28,000 sigs
The Safe Speed campaign demands a return to intelligent road safety

If he was an ACC he would probably claim he was on police business..

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Speed camera policy Kills

By my crude calculations an Impreza WRX Sti can stop from

140mph in 575 ft although this is based on known stopping distances at 60 and 80mph

I assume you added these figures together?

Whilst the reaction time bit is linear (double the speed for the same reaction time doubles the reaction time distance), braking to a halt from a given speed given constant g-force deceleration under braking is a square law relationship, so Paul is closer with 1000 feet in the McMasterson case.

Have a play with the braking spreadsheet:

http://www.safespeed.org.uk/braking.xls

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Paul Smith
Our scrap speed cameras petition got over 28,000 sigs
The Safe Speed campaign demands a return to intelligent road safety

I did but something like an Impreza is going to manage more braking effort at 100+ than at legal speeds due to downforce.

Isn't it?

Nah. I don't think there's ever been a road car with useful downforce, and certainly not an Impreza. Spoilers and so on tend to offset lift effects rather than actually contribute useful downforce.

What we do have to assist braking from high speeds is aerodynamic drag. It can be significant over 100mph.

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Paul Smith
Our scrap speed cameras petition got over 28,000 sigs
The Safe Speed campaign demands a return to intelligent road safety

Driving ban for 136mph policeman

The court heard McMaster was speeding on wet roads
A Highland policeman has been banned from the roads for a year after being caught driving at 136mph on a dangerous stretch of the A9.
Constable Blair McMaster, 28, was caught by a speed camera driving north at Daviot, south of Inverness, at almost twice the 70mph limit.

McMaster was fined £500 at Inverness Sheriff Court.

He will not lose his job but has been stripped of driving duties and will face a misconduct hearing.

Here:
http://news.bbc.co.uk/1/hi/scotland/4152841.stm