As an American I am sorry to say that it is drummed into us that America was built on the guts and integrity of the individual and that the rights of the individual take precedence over the good of society (take for example the debates on gun ownership), not to mention the unalienable right to drive. This is not the official line but an underyling part of the culture.
BTW when I was in France the speed limits were much higher than the US but it was rare to see them exceeded. In the DC area the Beltway speed limit is 55 and cars routinely go 70-75 with no enforcement.
This chain of logic is not really right unless everyone leaves the same distance to the car in front irrespective of the speed. A ten-mile stretch of road can safely contain more cars driving at 30mph (approx stopping distance 75 feet) than if they are driving at 70mph (approx stopping distance 315 feet). This reduction in the number of people who can be on the road then trades off against the reduced transit time, in addition to all the odd dynamic phenomena like the spontaneous traffic jams alluded to by Colophon
I seem to recall that the speed which maximises the number of cars a road can carry is about 40mph.
The 70mph limit on motorways is informally treated as a minimum speed, for cars at least. It’s rare to see a car travelling less than that.
I keep to about 80-85 if the motorway is pretty clear, and this feels like average speed as compared to other motorists.
And yes, I slow down for speed cameras, or if there’s a police car at the roadside or travelling alongside. This is normal driving conduct for virtually everyone here.
As for driving long distances at 55mph – that would seem absurdly slow for a clear, straight road.
Motorways, for example, have very wide lanes and extremely gently bends. If I were sat on a clear motorway for a long period at 55 I’d go out of my mind.
I’d need a Navitron Autodrive™ for a journey like that.
Car designers could optimize the gear ratios in the transmission to allow the car’s engine to run at optimum RPM for any speed. But as far as aerodynamics go, the shape of the car doesn’t matter. It will always be more efficient at a slower speed.
In the interest of stopping the smart asses out there. If a car was capable of travelling at supersonic speeds, the shape of the car could be designed to be more effiecient at just above mach 1 than it would be at high subsonic speeds. But, that’s really not an issue here.
The best thing for traffic flow and fuel economy is to spread out the traffic over the longest possible time and avoid ‘busy hours’. Many roads are over-utilized during the morning and evening commutes, which creates too much traffic to flow smoothly…causing breaking and acceleration = wasted fuel.
If local jurisdictions could work with large schools and businesses to stagger open/close times, and it was enough to ease congestion, this would be a big impact on fuel usage, and roads that are less congested are also safer.
I could go on about what a pain in the ass it was when there was a national speed limit. The department I worked for accepted equipment provided by a federal program (radar guns) and we had to make out these matrix reports on their use. Thos forms were anal as hell and it took a long time to fill out.
And I don’t care what anyone says, the majority of people oppose the 55 limit. During the 70’s and 80’s otherwise law abiding people spent hundreds of millions on Fuzzbusters, scanners, CB’s, “jammers”, C.H.I.P.s detectors, aircraft radios, and other devices just so they could break the law. The sales of those items now are nothing compared to what they were back then.
When else have you spent your money on something so you could break the law? I didn’t think so.
Multi-lane highways were specifically built for safe speeds of 65, 70, 75, even 80 miles an hour. It should be up to each individual state to impose it’s own speed limits. Congress put to death the failed experiment of a national speed limit in 1995. Let’s keep it that way.
I just took a two-week driving trip from New York City to Mount Rshmore and back. I can’t imagine how long such a thing would have taken if I was limited to 55.
I don’t mean to deprecate your experience, and I don’t doubt that this is the culture that the Government is trying to create, but I’ll point out this article that indicates that the state of South Australia has issued 1.5 million speeding fines in the last six years – in a state whose total population is only about 1.6 million. This makes it sound as though speeding in Australia is in fact extremely common.
Changing the speed limit is a demonstration of obstinate, willful ignorance of human psychology. Traffic adjusts naturally to the safe flow. This is why when there are a huge number of cars on the road, traffic slows down, and it speeds up when there are fewer. Obviously this doesn’t apply to residential zones, where “safe driving” means being able to stop suddenly for pedestrians, but on the interstate, a speed limit is just dumb.
Absolutely not true. Often, ambient speeds differ from state to state, based upon the state’s highway speed limit, the culture of the people driving there, the habits of the state police, etc. in policing the limit, etc.
There is, for example, a notable difference in driving habits from Ohio to Kentucky. This despite the fact that, for example, I-75 in Ohio is mostly straight, whereas in Kentucky it, perforce, has some curves and elevation changes. And driving south of the Mason - Dixon line will prove to anyone in a hurry that a posted 55 mph limit is simply laughed at by locals and transients alike, whereas the same limit in, say, Ohio, while not strictly adhered to, won’t be flouted in quite the same way.
It does not mean that speeding is more common than, e.g., in the U.S.: it probably just means that the South Australian police are more conscientious at catching and fining speeders, and work on a cut-off point closer to the nominal speed limit (e.g., they might book a car travelling at 105 in a 100 kph zone, when in most of the US the cut off might be 75 in a 65 mph zone).
Agreed. My only point was that while abby seemed to be saying that Australian culture considers speeding to be socially unacceptable, that article (with admittedly only one data point) suggests that there’s actually a large number of drivers getting a speeding ticket in any given year.
You may indeed be correct in your interpretation of that figure, and if so, perhaps it would be more accurate to say that in Australian culture, a “mild” speeding ticket is quite common, but “major” speeding is frowned upon.
I have no problem with localities cutting down speed where necessary, but there are an awful lot of highways in the US on which congestion is a non-issue and where the inhabitants regularly have to travel long distances for basic goods and services. In Iowa, there are many places that are an hour away from the nearest Wal-Mart.
I submit, based purely on my own experience (and therefore this is purely anecdotal), that this is because Ohio highways are teeming with radar cops in the same sort of way that Biblical Egypt teemed with frogs. As I mentioned earlier, I’ve just returned home from a trip through 16 states, and the (visible) police-per-highway-miles rate was much higher in Ohio than anywhere else except maybe home in New York.
The average person will drive at a speed where they feel they are safe, yet traveling efficiently.
What you want from a speed limit is to set a speed as close as possible to the average natural speed on the road, to encourage drivers to all drive at the same speed, and to provide a mechanism whereby insanely fast speeders can be punished.
So the smart way to do it is to remove the speed limit from a road for a while, and observe the flow of traffic (it doesn’t have to be a free-for-all - you can post signs saying, “Please adopt a safe speed. Reckless drivers will be prosecuted”). When you figure out what the natural traffic flow speed is on that road, then set the speed limit to be equal to that speed.
There are exceptions. If a road has tight, banked curves, the speed limit has to be set to the speed which causes the force of the car to still go straight down through the wheels on the bank. The road was designed for a particular speed.
Also, if the road has a lot of cross-roads on it, or stop lights, or animal crossings, or other hazards, reaction time analysis starts to play a part - you want people going slowly enough that they have time to react if a moose walks out onto the road in front of them.
But for the vast majority of public highways - observe the public, see how they like to drive, then set the speed limit to match.
Well, OK for most highways. Couple of “buts”. Not all highways are well designed, or built to design. I have been on roads that are underbanked, or actually banked the wrong way, on turns. Second, there are concerns other than the road itself. My street is a residential street where people can safely drive 40 MPH; it’s just a straight line. But if people go that fast I can’t get out of my driveway. The limit is 25 MPH.
Gas savings of a national 55MPH speed limit may not be as significant as one might expect.
While there are many areas where traffic flows freely,
There are many metroploitan areas where every weekday, and increasingly on the weekend, millions of commuters never get anywhere near 55MPH, thus a contribution to ‘wasted fuel’ that the 55 limit will not change.
I’m in the Boston MA area and the ‘rush hour’ (what a misnomer) is from roughly 7:30AM to 10AM and then from 3PM to 6:30PM. There are just miles of cars crawling along throughout the area. .