Respect pedestrians and cyclists

In addition to the general caution required of all drivers at all times, please remember to avoid splashing those of us on foot or bicycle. There is usually enough space on the road to move over enough that you won’t splash us, and when there isn’t you should slow down enough that your spray doesn’t hit us. Be observant and notice how far your spray is traveling and who is around. Remember, you have the right to walk, run, and cycle on the roads, but driving is a revocable privilege. So please, be sure to only make safe passes.

GMAC Insurance released their 2010 National Drivers Test results. The findings are interesting:

• If taken today, 18.4 percent of drivers on the road – amounting to roughly 38 million licensed Americans – would not pass a written drivers test exam.
• The national average score was 76.2 percent; a score below 70 percent is considered failing.
• Average test scores in 2010 continue to show a slight trending downward, from 76.6 percent in 2009 to 76.2 percent this year and a drop of almost 2 percent from the national average in 2008 (78.1 percent).
• With Age Comes Wisdom: The older the driver, the higher the test score. Males over 45 earned the highest average score.
• Factoring in margin for error, the average test score was significantly higher among males than females (78.1 percent male versus 74.4 percent female). Females also had a higher failure rate than males (24 percent female versus 18.1 percent male).

I’m not particularly surprised at the results. It can be hard to remember which of several similar answers is correct, which partially accounts for the low score; but this isn’t an excuse on something this important. The way I see it, the results are evidence that nearly one fifth of the licensed drivers in the country should have their licenses suspended until they re-pass their licensing requirements. Even this is optimistic. A survey like this can’t distinguish between book knowledge and its application. How many people can pass the test but never follow the rules afterward? This could be examined by including both the scores on the driver’s written tests and state accident data in the analysis.

Even in the wildly optimistic case that all drivers are able to re-pass the driver’s licensing tests after driving for a few years, it still wouldn’t be enough to ensure safe roads. The driver’s tests are currently only for the absolute minimum required knowledge and skill to drive a car on public roads, safe driving requires much more skill and awareness. A good step toward this level of driving is to take the ABATE or MSF motorcycle safety test. I think that passing one of these courses should be a prerequisite to applying for a car learner’s permit. This would make the roads much safer.

The GMAC test is online so you can try it yourself. Then you should read my page on safe driving around bicycles.

Source: 2010 GMAC Insurance National Drivers Test via AOL Autos via USA Today. Note that this was an online survey.

Notice this pass consists of:

1. A dangerously late and close pass with partial lane change,
2. followed by completely changing lanes, well after the cyclist.

Since the driver stays in the far lane for a while, it is clear that they had space to move over early and make a safe pass, but for some reason, chose not to. To make it worse, the driver often seems to forget the extra width of their dual rear axle and trailer. Instead of nearly hitting the cyclist, the driver could have easily made a safe pass:

Notice the steps of the safe pass:

1. Begin to move over well before reaching the cyclist.
2. Pass at a safe distance. Keep a minimum of three feet between the closest points of the car or truck and the bicyclist. On fast roads with large vehicles, the minimum safe distance may be larger.
3. Move back into the lane well after passing the cyclist. Don’t forget to leave room for your trailer.

I’ve driven some of the narrower roads in the area while pulling a large trailer with a full size pickup truck many times, so I know that—even in a large vehicle—it is easy to pass cyclists without endangering them. So, I’m not sure why this type of pass is common. It isn’t the typical dangerous driver intentionally buzzing a cyclist; it doesn’t seem fit the usual explanation of driving aggressively to feel faster. The Indiana pass could possibly be mostly done by drivers who like doing slipstream passes, where they close dangerously close to the car they are passing before moving over, trying to draft a little. Beside the normal danger of a drafting pass on open roads, it is ineffective when a car is passing a bike, because the car is almost entirely outside the cyclist’s slipstream. It seems more likely that the Indiana pass is the result of inattention, poor depth perception, and general unawareness. I don’t know what combination of these is the cause, but hopefully this post will contribute a little to stopping the Indiana pass. Remember to keep enough space between yourself and the other cars and cyclists that when the person in front of you makes an emergency stop, you will be able to avoid hitting them.

Notes:

• Check out my page on Safe driving around bicycles, including more on passing.
• The illustrations require a browser with SVG animation support. If the play button is invisible or doesn’t work, please upgrade.

Static friction is greater than kinetic friction.^*

In other words, if you aren’t sliding, it is easy to stay not sliding. Once you start sliding, it is hard to stop.

So stop stomping on the pedals when you drive. You’ll just make your wheels spin or lock and slide. When you spin your wheels, you are just turning the snow into an ice slick, making it harder for you and everyone after you to start or stop. So please go easy on the pedal mashing.

Suggested reading:

• Friction on Eric Weisstein’s World of Physics
• Car Talk’s Official Click and Clack Winter Driving Rules

^*Except for some cases you probably won’t encounter.