Not really sure I get the point?
PH is easy to understand how long it will take to get from one city to another.
60 MPH = 1 mile per minute
Easy to work out
60 miles = 60 mins
30MPH 60 miles 120 mins (double)
etc
Switching to km/h
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Not really sure I get the point?
PH is easy to understand how long it will take to get from one city to another.
60 MPH = 1 mile per minute
Easy to work out
60 miles = 60 mins
30MPH 60 miles 120 mins (double)
etc
Soldato
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The maths is easy, its the relating the mile to an actual distance.
As I said I bet the vast majority of the population could not mark out a mile or even close, hence they cannot claim to have a sound grasp on their speed since they are not equating time to distance in actual measurement, they are equating time to something they cannot demonstrate.
Think of it this way, how far do you travel in 10 seconds at 60Miles Per Hour?
How far do you travel in 10 seconds at 28Metres Per Second?
There is a car visibly braking about 60 metres in front of you, at 30MPS how long will it take you to get there, at 60MPH how long will it take you to get there?
When assessing safe distance its far easier to judge distance when the measurement of your speed is in the same measurement as what your eye can see can be reasonably quantified.
You really think all those experienced drivers out there are busy doing mental arithmetic?
The use of imperial measurements in driving has no bearing on safety at all.
Calculations are done when approaching an object but it's subconscious and experienced based rather than getting out a laser rangefinder and a calculator.
Maybe I don't understand.
If there is a car visibly braking in front of me, would it be relevant for me to work out in my head how long it would theoretically take to brake? Surely by the time I work out and the concentration lapse it would have already been to late since I would have already crashed???
As for assessing safe distance there there's the two second rule to follow which I think is more practical.
If there is a car visibly braking in front of me, would it be relevant for me to work out in my head how long it would theoretically take to brake? Surely by the time I work out and the concentration lapse it would have already been to late since I would have already crashed???
As for assessing safe distance there there's the two second rule to follow which I think is more practical.
Soldato
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No of course not.
I am trying to get across the point that people are oblivious to how fast they are really travelling in concept of the space they can see.
Yes MPH is a specific measurement, but based on the fact that the limits are there for safety reasons would it not make more sense to relate them to a time space measurement that people would actually RELATE to.
I pretty much abide by the 2 second rule myself, most don't however.
The whole point of my post was that even the most idiotic muppet out that can understand that at 30 metres per second when hes driving 5 metres behind someone at 70mph hes got less than 1 second gap. There is no mental arithmetic needed.
Look at it this way, I go and take a photo out the front of my car, stationary.
Then I say approximately where would you be compared to the cars alongside the road in 1 second at 30 metres per second, I bet a far higher number of people would be able to give an accurate representation of where they would be than if I asked the same question and said your travelling at 30mph.
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Might account for all the ****s out on the road there!!
"Sorry mate - I did see you, but I forgot to carry the one during my preliminary calculation of my braking coefficient by factoring 3/5ths used sintered pads on 9/11ths part-worn radial threaded tyres at 42ºC against a road surface of 21.86ºC with 18 mega-μ of traction... and of course I was busy calculating it all out on my iPhone!"
But will converting everything to metric change any of this?
And if they cannot demonstrate it, how come drivers and riders (usually... well, more often than not) still manage to stop their vehicles before hitting something?
Safety actions are based on much more than just the precision of measurements, no matter how fast the brain can measure them.
1/. About 300 yards.
2/. 280 metres.
3/. Well DUH! 2 seconds... minus, of course, the time derived from the complicated calculations to factor in all the variables that ultimately determine the car's deceleration rate, plus the time derived from the complicated calculations to factor in all the variables that ultimately determine my own deceleration rate, if indeed I am not being a retard and actually apply the brakes, while assuming steering around the hazard is not a better option... What's that? What do you mean I already crashed before the word 'calculations'??!!
4/. See above, but likely crashing a mite earlier.
"Only a fool breaks the two-second rule".
There's a reason that is taught to new drivers, rather than hammering the exact thinking and braking distances under ideal conditions into their heads.
IIRC There was an attempt to "Metricate" tyres back in the 80's (IIRC, some were fitted to the Rover Metro)
The problem was, being "Non Standard" they were much more expensive than "Normal" tyres of similar spec so that when owners needed new tyres they would buy a set of imperial rims and fit "Normal" tyres instead.
So the idea flopped!
Soldato
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Not metric per se but an imperial measurement that gives a speed that's actually relevant to the space time our brains can actually relate to visibly in our field of view.
I would actually argue that most of the time when something unexpected happens they don't cope. The reason they appear to cope well is that the actual number of times it becomes relevant they were driving too close / too fast / whatever is a considerably small fraction of 1%
Of course
I was never taught that, although I do pretty much apply it.1/. About 300 yards.
2/. 280 metres.
3/. Well DUH! 2 seconds... minus, of course, the time derived from the complicated calculations to factor in all the variables that ultimately determine the car's deceleration rate, plus the time derived from the complicated calculations to factor in all the variables that ultimately determine my own deceleration rate, if indeed I am not being a retard and actually apply the brakes, while assuming steering around the hazard is not a better option... What's that? What do you mean I already crashed before the word 'calculations'??!!
4/. See above, but likely crashing a mite earlier.
Did you do 1 mentally or have to calculate it, What would have been your view before you actually thought about it?
I didn't say you needed to stop in 3I just said how long till you got there
"Only a fool breaks the two-second rule".
There's a reason that is taught to new drivers, rather than hammering the exact thinking and braking distances under ideal conditions into their heads.
Interestingly how long a second is is actually another thing we as humans are generally quite poor at judging.
Don't get me wrong I don't think we would change to decimal, but if we did would it not be a sensible thing to take a look at the measurement we were moving to and see if they gave any benefits. It would not be hard to change the measurement in simulators, apply real world type "events" and see if they had changed peoples actions.
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Because cars are designed to have the controls on the side of the car with the relatively small gearbox. In a RHD car the controls are on the side of the car with the relatively large engine block, so the driver looses some front crumple zone and is more likely to suffer injuries from parts intruding into the cabin. This applies to front transverse mounted engines, in the Chrysler Grand Voyager it was the difference between 3 and 1 stars in Euro ncap. If you have a front longitudinal mounted engine like in a BMW then there is probably little to no difference.
Edit:
This is OcUK so I need to add: I know you can probably cite 15 front transverse mounted engines where this doesn't apply, don't be a stickler.
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Out of interest, when you say "in line with the rest of Europe" can you explain to me how the EU has actually benefited us?
All I see are negatives, another country (well, Brussels) telling us what to do all the time, leaving us as the dumping ground for people that other countries don't want, etc.
All I see are negatives, another country (well, Brussels) telling us what to do all the time, leaving us as the dumping ground for people that other countries don't want, etc.
While I found your initial proposal interesting, I do side with Culinia on one aspect. We use speed as much for long-distance calculation, i.e. at 60mph I know easily how long it will take to reach somewhere 27 miles away at that speed.
Measuring the distance in metres isn't so much of a problem as it is easy to convert to KM under the decimal system. However measuring the time unit in seconds is. There is no proper metric/decimal time unit i.e we have inherited this 60s/60min/24h clock rather than say 100s/100min/10hr. So if we are travelling at 28m/s it is a right ballache trying to equate that into the sort of distances/durations we typically travel in our cars. Nobody ever does car journeys in seconds, at least not in a situation where they need think about how long it might take to get there. People think about journey times typically in terms of fractions of hours or possibly units of 5mins for local journeys.
So 28m/s, everyone knows that is 0.028km/s, that's easy. But could people with average arithmetic easily know based on that how long a 100km journey will take? Sure, over time we'd effective learn some common calculations, rules of thumb etc.
Again, your point about whether people could measure out 1 mile holds some merit, but why does it matter? I don't need to know how far a mile is (someone has already done the hard work for me by creating maps, roadsigns etc), I just need to know how long it will take to get there at a given speed.
Compared to getting used to driving on the other side of the road, that assessment is marginal at best. Plenty of the vehicles will receive 5 stars with RHD so it is a moot point, and only applies to front end collisions.
It would make more sense to drop all the speed limits - ie all the 30 signs would now mean 30KPH.
We would all be safer, the planet greener and the Daily Mail could have something to campaign for / against
30kph is a miserable speed to travel at, and some of the so-called 30mph areas that were formerly 40mph would now be 18mph. Whilst any impact would be lesser the misery and frustration from driving at 36mph in a former 60mph limit would likely just mean many would ignore the limits.
The limits have to balance safety and making progress.
MKW
As for having the speed limits in m/s that would just be a meaningless measurement that bears little resemblance to the length of the journey which is why they use KPH and MPH. Leave m/s to physics lessons and exams.
"I am doing 48ms and I have 36 km to go, how long will it take me?"
"I am doing 30mph and I have 18 miles to go, how long will it take me?"
At this point the simplicity favours xph not x/s
The biggest issue I have here is the whiners saying "we don't learn this at school" as frankly it is among MILLIONS of things you don't learn at school. Once you leave school, the real learning begins and if you are learning to drive it is this point when you should start learning time and distance in the units applicable. Sure, you want it easy in units you learned at school, but the rest of us are fine with it. You guys just need to man up and learn about imperial as it is just another example of the youth of today they want it all handed to them on a plate. I had to learn KPH when I lived in Cyprus, I had no problems so you youngsters can do it far more easily as you even grow up with you parents using MPH.
Soldato
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Some european country did this, was it sweden in the 70s or something like that.
I remember reading about it and the impact was far far less than expected.
On UK roads though, today with current traffic volumes it would be chaos I think. Imagine motor way access roundabouts!
Saying that I am sure its something that given technology could with investment and time prove quite seemless.
But whats the real benefit in driving on the wrong side
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The brain will relate to whichever space-time they are taught during driving lessons.
If you walk at 4kph, but are taught to drive in mph, you will continue to measure your driving speed in mph.
I measure small distances (sub-metre) in inches, yet measure small components in millimetres because that's the context in which I experience things. If you talk to me in centimetres, I have to convert it to inches or gauge it by the length of a pocket/desk/draughting ruler.
I ride the roads every single day. I hear far more tyre screeches and horns blatting per month than I do vehicle impacts. They cope well enough.
Depends on what aspect of the scene you examine.
If it is just pure speed limits, then you're right. More often, people are driving too fast/close for the conditions they're in. Speed is a factor, but it is the speed relative to the situation and not whatever the sign says... and it is this part that has been omitted from many studies, resulting in the whole 'Speed Kills' mentality.
I've known someone crash their bike and lose a leg while doing 15 in a 30. Everything they did was well within the laws of the road, but they were going too fast for the conditions.
Many people make the mistake of counting from one, rather than zero.
But that very phrase, "Only a fool breaks the two second rule", is meant to be spoken almost in a sing-song and to take just over 2 seconds to say for the average person.
Personally, as a drummer and martial artist, I measure time in fractions of a second and would like to think I'm pretty good at it.
Perhaps... but it would be saturated with trouble as it would take generations to re-educate everyone.
Actions will not change.
As is, people blatantly know but still exceed those limits. I myself was bashed off my bike (I was stationary at the time) the other month by a car doing 60 in a 40.
Speed limits are changed on roads quite often and no-one pays any attention. Speed cameras are still generating a fortune in tickets, so people probably just don't give a toss and will knowingly speed, regardless.
Changing the number on the signposts will make almost NO difference.
You must first set the limits and make it completely impossible for people to exceed them, be it mechanical/electrical vehicle restrictions, neural programming or whatever... or perhaps just make vehicles that drive themselves. That way we can all enjoy our iPhones in complete safety!
And 130mph on motorways
My car wouldnt make it!
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Do you think thats accurate though?
From my experience its very rarely accurate now, traffic density, number of traffic lights, car calming measures, people deliberately going excessively slow, slip roads backing up onto duals so causing braking and stop start etc etc. I cannot think of a journey I have made in 12 months where if I had applied simple multiplication to 27 miles x 70 mph would have given me an accurate time for the journey.
Its precisely that mind set that I believe causes the unplanned speeding, working out that its going to take 20 minutes to get somewhere and being held up for 3 minutes early on, causing them to recalculate and put their foot down in order to "make up lost time".
I do a 20 mile commute, its mainly 60mph A road (single carriage) and my average speed according to onboard computer.. 42mph I checked this morning. Thats about right, it actually seems to take me 45 mins but by the time I leave the office, get in car and get out of car collect coat etc at the other end I am probably only actively driving for 35-40 mins of the 45.
AA route directions suggest 41 minutes for the journey. The assumption that its mainly a 60mph road so should take me around 20 minutes is massively wrong. My sat nav when I first did the route suggested 35 mins iirc.
Also in these days who hasnt got a sat nav that can provide a far better estimate on how long its going to take to get somewhere than doing mental arithmetic in a car on a journey.