Sunday, February 04, 2007

Speed Kills ?

There's an interesting article in The Sunday Times this morning, right here in fact, which is one of those "opinion articles" that is always written in response to another "opinion article", mainly to fill space in the non-news sections of the Sunday papers - the non-news sections taking up ten times more space than the minute news section.

Its in response to the BBC's tv programme "Top Gear" last week during which they showed the footage of one of their presenters crashing a jet car at 288mph during a speed record attempt - by some unknown means the presenter eventualy survived and was on the programme to joke about the incident.

Of course it provoked fury amongst those who campaign for all vehicle drivers to be fined and jailed on each and every occasion that they exceed any arbitory speed limit, speed limits that would be lowered to less then walking speed if the campaigners had their way, making cars out of foam rubber would be their next step too.

The Sunday Times article argues that its not speed that kills, but inappropriate speed, and in that respect the writer is quite correct, the speed limit outside most urban schools in the UK is 30mph but only a fool or those in leave of their senses would suggest that that is an appropriate speed to drive at when the school is turning out up to a thousand pupils at 3.30pm.

Unfortunately the writer of the article then goes on to try and back up his argument with "facts", "facts" that show apparently that only 10% of accidents involve excessive speed and that only a third of that 10% were in excess of the speed limit.

The problem with producing such figures is of course that they are so inaccurate as to be useless.

No-one who has just been involved in a road accident which involved them breaking the speed limit is ever going to tell a police officer "oh yes, I was definitely doing 40mph in this 30mph limit, at least 40, more like 50mph actually" and the forensics of calculating speed from data gathered at the scene depends on measuring skid marks, which may actually be completely absent depending on when and how hard the driver started braking. Add to that completely unreliable witness statements, "he was definitely speeding, oh yes, I'd say 60mph easy, maybe 50...or 40, definitely speeding though, no I was looking in this shop window" and you see that the gathering of speed statistics only works when you have well defined skid marks on a dry road and even then you can only estimate what the dissipation of the speed was according to the model of the car and the condition of the brakes at the time, and even then you only get a rough idea of what the impact speed was if you know what the speed was at the start of the skid - in other words the only way to accurately measure speeds is in commercial vehicles with tachographs - cars do not have them.

What is unarguable is that the introduction of speed cameras on every street corner in the UK has revealed that almost every driver in the UK drives above the speed limit at some time, the few who haven't yet picked up a fine and licence points are simply the ones who are good at spotting the cameras and slowing down in time.

Simple truth is - everyone drives in excess of the speed limit sometimes, not just 10%.

As a bullshit Sunday newspaper filler its not a bad article though.

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