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Device Stops Speeders From Inside Car
frdmfghtr writes "CNN reports that the Canadian government is testing a new anti-speeding device." From the article: "The system being tested by Transport Canada, the Canadian equivalent of the U.S. Department of Transportation, uses a global positioning satellite device installed in the car to monitor the car's speed and position. If the car begins to significantly exceed the speed limit for the road on which it's traveling the system responds by making it harder to depress the gas pedal, according to a story posted on the Toronto Globe and Mail's Website."
What a bunch of fucking nonsense.
Look, traffic engineers know, and have known for a very long time, that the safest speed to set speed limits at is the 85% percentile speed: the speed which 85% of the free-flowing traffic on that particular road travels at or below. This is because the large majority of drivers are reasonable and prudent, and while they wish to reach their destination in a short amount of time, they also wish to remain alive and unwrecked.
If traffic engineers want this speed on a stretch of hypothetical road to drop, they do this by changing the road surface. Narrows, curves, crests, inclines, will all reduce the 85th percentile speed.
Setting a speed limit lower than the 85th percentile speed doesn't reduce the speed at which traffic flows. I'm going to repeat that again, because it sounds vaguely important:
Changing the speed limit doesn't change how fast people drive. The safe speed for a road is determined by the road design and the road conditions, and *not* by some arbitrary number on a sign.
The notion that traveling at the posted limit +5 is more dangerous than traveling at the posted limit, or than traveling at the posted limit -5, is reasonable only if the posted limit reflects the 85% percentile speed.
Sometimes it does. Some states even have it written into their laws that that's how speed limits are determined.
But more often it does not. More often, speed limits are set artificially low, in order to provide a source of revenue for the state. If you set a speed limit below the 85% percentile speed, people will generally ignore it, drive at the speed dictated by road conditions and their ability, and then you can ticket them for speeding.
Here are the actual conclusions of that study I linked to just above:
Sorry, but you got a few things wrong. Although you might be essentially right, let me be a Fact-Nazi (got it? A German, calling himself a Nazi. Funny, huh? Aw...):
1. The mandatory check-up (so-called "Hauptuntersuchung") is every _other_ year, and only after four years for a new car. Still, judging from what I see on `Pimp my ride', it is possible in the states to drive cars that would never be allowed on public streets in Germany.
2. Nobody is "happily driving at 250+ Km/h". Yes, I have been overtaken by the occasional Porsche doing 300 km/h (~190 mph) and Mercs at 220 km/h are not exactly a rare sight, but these people are notorious for closing up to an arm's reach of your bumper with headlights flashing; and they are generally considered arseholes with tiny wangs.
3. About 60% of the Autobahn network (that's an estimate, I couldn't be bothered to look it up) have speed limitation, typically 120 km/h. That doesn't stop people from speeding there, but they get caught sooner or later (the Autobahn police squad sports disguised, camera-fitted cars with appropriate engines)
4. From what I hear from friends with American licenses, you are right about driving licences.
5. Accidents don't happen on Autobahns. They happen on county roads with sharp curves, crossroads and narrow passages. Due to the Autobahn's construction (or any other Highway's, for that matter), head-on crashes are nearly impossible, and deadly crashes are much rarer than they are on county roads (believe me, I am an EMT...)
The poster seems to be under the delusion that speed limits are always tied to the current maximum safe speed.
This is absurd, as other factors can be at work:
political (the town I live in has 5mph lower speed limits on exactly the same roads and road conditions as the towns around it - and not coincidentally is the first town in the US to use photo-radar).
legal - in the US, every state (except perhaps one) has an absolute maximum for speed limits. Clearly some roads and vehicles are capable of being driven safely at much higher speeds on some road segments in those states. Not that long ago, the idiot Jimmy Carter forced a 55mph maximum speed limit throughout the US, that lasted until 1994. The interstate highway system was built for much higher speeds (I believe 75mph) and the Kansas Turnpike for 80mph, it's previous speed limit.
safety for non-familiar drivers - a road can have conditions which make the maximum safe speed lower than the apparent (to non-familiar drivers) safe speed. The authorities may choose to set the speed limit lower to compensate.
weather - the speed limit may be lowered to compensate for common but not continuous weather conditions such as high winds.
Traffic engineers used to set speed limits, in the absence of other factors, determining the 85th percentile speed of unconstrained drivers. In other words, presumably 85 percent of the drivers, based on their experience and perceptions, drove at or below the maximum safe speed. They would, of course, set them lower at hard to see hazards such as hidden curves.
If one is going to have such a system, soft but effective feedback seems much better than hard limits.
BTW... some cars have unadvertised built-in speed limits. My 2001 Toyota Sequoia appears to have a 100mph limit. One day on a storm chase, on a very good road with almost infinite visibility, we tried it, and at 100mph the engine refused to go faster, even though it clearly had the capacity. I suspect this may be because they didn't want to put bigger tables into the engine computer.
The only good weather is bad weather.
In regards to your ambulance point: actually, on the way to accident scenes, those things do go well over the speed limit. So do police cars and fire trucks. Once the person is in the ambulance, yes, they slow down - the person is already getting medical attention. But shaving 30 seconds off a 5 minute trip to get to the guy having a heart attack can easily be the difference between life and death.
Also, there are times (rare, yes) when speeding to the hospital is not the worst idea. The hospital where I live is slightly out of town, and to get there you have to go on a highway of sorts. The limit is 60km/h for part of it. Oh a straight road, no lights, no fast turns or merging traffic, if it was 4 in the morning and someone was dying in my backseat, going up to 100 would not be an issue.
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As a New York City Paramedic, I agree. Here in New York State, we are never alowed to exceed the speed limit, no matter what the scenario. We are (same goes for FDNY) not even allowed to take red lights. Only the NYPD can do that.
The sick person being transported to the hospital is already sick, there is no exuse to jeopardize the public after the fact. The same holds true for responding to calls.
There have been quite a few case lately were EMTs or Paramedics have received jail time for their reckeless driving.
On Highways I agree that speed limits do seem restrivtive, however, in town they are very intelligent. The speed of a vehicle has a large impact on the severity of accidents when pedestrians are impacted.
p 7.html check paragraph 6
http://www.nisu.flinders.edu.au/pubs/bulletin9/b9
In areas where there are many driveways, pedestrians on the side of the street, cyclists, etc, speed needs to be regulated.
Here are a few sections from another article:
Are pedestrians at risk from speeding vehicles on city streets and suburban roads? Yes. The second largest category of motor vehicle deaths, after occupants, is pedestrians, and 69 percent of pedestrian deaths occur in urban areas. The speed of vehicles involved in pedestrian impacts is a major determinant of the severity and outcome of injury. There is a much higher ratio of deaths to injuries where speed limits are higher - nine times as high where the speed limit is 55 mph as on roads where it is 30 mph or lower. A federal study of pedestrian crashes found a positive correlation between speed and injury severity. In addition, vehicle speed influences the likelihood that a pedestrian will be struck in the first place because a driver cannot stop quickly enough. One study found that, even in residential zones, almost 20 percent of vehicles were traveling at more than 30 mph when they struck pedestrians. Some cities are using new approaches to slowing urban traffic to reduce pedestrian crashes, especially in school and work zones.
What is the role of speed in crashes? Speed influences crashes in four basic ways:
It increases the distance a vehicle travels from when a driver detects an emergency until the driver reacts.
It increases the distance needed to stop a vehicle once an emergency is perceived.
Crash severity increases by the square of the speed so that, when speed increases from 40 to 60 mph, speed goes up 50 percent while the energy released in a crash more than doubles.
Higher crash speeds reduce the ability of vehicles and restraint systems to protect occupants.
http://usww.com/homepage/starteam/speed.html#s1