Safe Speed Forums

3 times in 6 trips now on the south M25. Origional time i mentioned on friday last week, Wednesday pretty much the same but only for a mile or so becaue it was close to a junction and tonight an accident at clacket made the M25/M26 clear all the way to the M20

Mmm, lets see.

125mph = approx 60 yards/sec
thus the dog was 0.5 - 0.66 secs ahead.

In that time, you reacted, choose what to do, and pulled off the action.

You should contact Maclaren immediately.

I agree with your maths, but life is never simple as that. You overlook the point that the driver braked too, therefore slightly extending the ETA, not by much but perhaps enough.
It is perfectly possible for someone to react within that time if they were on the lookout for such danger and had planned for it.
I for one wouldn’t take such described distances as gospel.

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Views expressed are personal opinions and are not necessarily shared by the Safe Speed campaign

I think you'll find that Richard C is the holder of an FIA International Competition Licence and is a highly competitive and well-respected rally driver. 'Nuff said!

hummm

ive been driving a very quick car recently, admittedly not on the public road... but it suddenly makes 80mph seem remarkably pedestrian... and 40 feels like walking speed.

(thats the subjective feel of driving the car at those speeds, not the feeling relative to the car's cosiderable top speed)

it made me question my views on this thread..... but i've not made up my mind how yet !

ANY speed can be dangerous.

100mph on wide, dry road = safe.

25mph on packed snow and ice = bye-bye control, bye-bye car, bye-bye people waiting at bus stop!

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www.thatsnews.org.uk / www.thatsnews.blogspot.com / http://thatsmotoring.blogspot.com/

Best estimates of human reaction time is approx .7 of a second to an expected event - allowing .5 sec for 'processing' and .2 sec for 'movement'. Ergo braking would not have happened before dog splat, even if it was constantly expected that such an intrusion into the car's path was about to occur.

(check sources such as Visual Expert if you like)

If OP is a well respected rally driver then cognition of speed and distance should be better than this ..... BS.

you forgot to add on good tyres, no debris on road etc etc
the higher the speed the higher the number of disclaimers seems to get !

to the extent above a certain threshold perhaps the probabilities add up to = unsafe.



studded tyres ? easy peasy... slalom between the people at the bus stop

Try this http://www.fetchfido.co.uk/games/reaction/reaction_test.htm

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Driving fast is for a particular time and place, I can do it I just only do it occasionally because I am a gentleman.
- James May

Thanks for the link - it's a nice test toltec - even a middle aged git like me can get that down to .21 of a sec or so .... but it's one simple task in reaction to one known event. This doesn't apply to multiple possible inputs and multiple possible actions, such as driving in the OP. The .7 I quote is from research into driving reaction times.

You must be joking!
Can you quote your source please? I believe it to be total BS.

The reason why I say that....
My reaction time.

Don't bother quoting the HC, the figures that's based on are accepted as being unrealistic, and that only applies to braking, not steering. Don't forget, all Richard had to do was steer the wheel - his hands are already on it so no delay there.

If a driver EVER depends on his reaction time he has already messed up royally, or is subject to some significantly unusual event.

In normal driving the process of anticipation makes practical reaction times negative.

The most common reason for the failure of the anticipation process is distraction.

The entire model of a 'driver reacting to a kid running out' is misleading and theoretical. It simply isn't what normally happens. We need to be far more concerned about factors that cause drivers to fail to correctly assess a developing hazard.

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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

The point I was trying to raise was that the test uses an expected event.

As you say driving is more complex however as Paul states above it is also seldom about reaction times. Your ability to process multiple inputs and correctly anticipate possible actions is part of what defines your ability as a driver imho.

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Driving fast is for a particular time and place, I can do it I just only do it occasionally because I am a gentleman.
- James May

Thanks Cooperman. I was going to post that ericthehalfabee was about right. I suppose you will agree that competition as well as years of driving fast and safely makes for fast response in emergency situation.

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Richard Ceen
We live in a time where emotions and feelings count far more than the truth, and there is a vast ignorance of science (James Lovelock 2005)

You are probably right about the recollection of distances smeggy - It might have been as amuch as 50 yards. The braking was associated with steering happened as one but the speed was not greatly diminished as I passed the dog. The dog appeared quite suddenly, running unseen from a farm gate into a road. Reason for quoting it was not to suggest special skill as such, simply that speeds in excess of 100 do not necessarily result in disaster when anything unexpected happens. Skills developed from actually driving enthusiastically and learning car control at an instinctive level surely lead to safer driving.

I agree with Paul that one should not simply react and 17 years and more than half a million miles I probably look further ahead. I can't say whether the avoiding action was simply reaction or I had lifted off a bit being aware of the farm nearby the road.

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Richard Ceen
We live in a time where emotions and feelings count far more than the truth, and there is a vast ignorance of science (James Lovelock 2005)

Well my family and mates must be fighter pilots then, i go an average around .22, the misses about the same and best mate around .2.