Speed limits

valhalla360 wrote:

toedtoes wrote:

valhalla360 wrote:

bgum wrote:
If you don't believe speed kills just look at the pileups with 40-50 cars. Those who are driving the limit are not the problem the speeder is the problem.

Typically, that is poor visibility. They are rarely doing the speed limit. It's more often someone nervous who is traveling substantially below the average of nearby traffic (high differential speed).

Of course, until we have wide spread adaptive speed limits, the limits posted for normal conditions will be too much for icy white out conditions.

According to the NHTSA, approx 94% of car crashes are caused by drivers.

Of those, over 40% are "recognition mistakes" - this is distracted driving or simply not paying attention.

"Decision errors" cause 33.3% of crashes - this includes speeding, tailgating, driving recklessly, and incorrectly judging the speed of other cars or space the driver has to complete an action (e.g., passing another vehicle).


"Driver performance" causes more than 10% - this is oversteering, losing control, etc.

Other errors not related to performance, which mostly is the driver falling asleep causes 7%.

Unknown or unspecified reasons cause 8%.


Note that "driving too slowly" is not listed in any of these categories.

That suggests that your claim that those pile ups are caused by some nervous nellie is inaccurate. It is NOT the nervous nellie who causes the accident - it is the driver who is distracted or is making decision mistakes. If that driver were not distracted, speeding, tailgating, miscalculating speed of or space between other vehicles, then the collision would not have occurred.

The nervous nellie does NOT hit other vehicles - other drivers hit the nervous nellie. And they do so because they are distracted or making bad decisions.

In a foggy situation, with a speed limit of 55mph, one should expect and be extra observant of vehicles driving much slower, or even stopped traffic. A driver who chooses to drive 55 in that situation has no one to blame but himself if he hits a car going 45mph.

You've found a flaw in the way crashes are reported. The cop is almost never present to see the accident unfold. They typically have little or no evidence to go off of (usually conflicting he said/she said), so they typically fall back following to closely for conditions or driving too fast for conditions...well because if they weren't there wouldn't have been a crash.

That's great in terms of handing out a ticket or determining who's insurance pays up. It's not very useful in determining how to fix the problem.

If there is a 100 car pile up, that suggests 99 cars selected a speed they felt was reasonable and 1 felt they needed a significantly slower speed...but again, if the average speed is 50mph in a 70mph zone, it's not relevant to setting the speed limit.

Actually, this data was based on a project where the NHTSA went out to the accidents with the police and questioned the drivers at the scene and then compared those statements to the cars' data and the skidmarks, damage to the cars, etc.

As such, the report shows that no one stated "he was driving too slow" as the cause of the accident. Yet many many people stated they were distracted, speeding, tailgating, or had fallen asleep, etc. and that's why they hit the other car.

So your argument doesn't hold water.

In a 100 car pileup, it does not mean 99 people were going one faster speed and one was going much slower. That is your bias showing. All it means is that 99 people failed to not hit another car.

It could have been caused because there was a large piece of debris in the roadway and the first car swerved to avoid it thereby causing the cars around it to swerve and all the cars behind were following too close to stop in time.

It could be that one person was driving significantly faster than everyone else and didn't see the car ahead due to fog and hit it causing a chain reaction.

It could be that someone was trying to read a report on the way to work while driving and swerved to make their accident causing a chain reaction.

The idea that all (or even a significant number) of these pile ups were caused because one person chose to drive too slow is simply trying to justify speeding - and it doesn't work.

In reality, the best way to avoid a pile up is to increase the space between cars. If the car in front of you swerves, slows down, or farts, you should be far enough back to not have to slam on your brakes. And if you avoid hitting them and take a huge sigh of relief, you were still too close.

That's why the three second rules works - because the faster you are going the more room between you and the car in front of you. Because the higher speed requires a greater stopping distance. But most people maintain one car length or less between them and the car in front of them at any speed - because heaven forbid someone is allowed to move over in front of them. Heck, they might have to drop their speed from 70 to 67 for a minute in order to reestablish that space and that is unacceptable.