DiscussWorldIssues - Socio-Economic Religion and Political Uncensored Debate - View Single Post - What you think right before you might get into a car crash

**YonkFiorc** · 01-14-2011, 06:58 AM

An edge over what? Going that slow is probably as much of a hazard as the junk in the road. You seem to be the only person that engages that unnecessary level of caution when driving at night.

No, he's not. You drive for the conditions. If that means you can only do 40mph because of the risk of hydroplaning, or because the roads are so wet your stopping distance has increased by a factor of 8 then that means you go slower.

Most of the highways here are well lit. Meaning that you can drive them without any headlights at all and still see the road fine. But what really helps more than anything else is that our lane dividers have reflectors built in. Headlights and running lights also severely increase your visibility to other drivers as much as helping your own vision. While your lights may only illuminate a few hundred feet, your lights are visible from THOUSANDS of feet away by other drivers in normal weather.

I will be the first to tell people that I do speed.

But in poor visibility conditions such as rain, fog, snow, I slow down for visibility, and traction reasons. If I can't SEE a car in front of me, and my visibility is limited to 200ft, then I'm NOT going to be going 70mph (102.6ft/s). In all likely hood I'll be closer to 30mph. 30mph is 44ft/s, which if you are being paranoid thats enough time to react and stop when your visibility is 200ft. Thats about 4 seconds, and if you are ready to stop because you are actively looking for hazzards. I will even go slower. I've done 10 to 15mph on the highway before because of weather.

Now, if one is NOT paying attention to the road, then no amount of reaction time can save you because you are being reckless.

Read this. http://www.visualexpert.com/Resources/reactiontime.html

Expectation

Reaction times are greatly affected by whether the driver is alert to the need to brake. I've found it useful to divide alertness into three classes:

Expected: the driver is alert and aware of the good possibility that braking will be necessary. This is the absolute best reaction time possible. The best estimate is 0.7 second. Of this, 0.5 is perception and 0.2 is movement, the time required to release the accelerator and to depress the brake pedal.
Unexpected: the driver detects a common road signal such as a brake from the car ahead or from a traffic signal. Reaction time is somewhat slower, about 1.25 seconds. This is due to the increase in perception time to over a second with movement time still about 0.2 second.
Surprise: the drive encounters a very unusual circumstance, such as a pedestrian or another car crossing the road in the near distance. There is extra time needed to interpret the event and to decide upon response. Reaction time depends to some extent on the distance to the obstacle and whether it is approaching from the side and is first seen in peripheral vision. The best estimate is 1.5 seconds for side incursions and perhaps a few tenths of a second faster for straight-ahead obstacles. Perception time is 1.2 seconds while movement time lengthens to 0.3 second.

01-14-2011, 06:58 AM	#11
YonkFiorc Join Date Oct 2005 Posts 425 Senior Member	An edge over what? Going that slow is probably as much of a hazard as the junk in the road. You seem to be the only person that engages that unnecessary level of caution when driving at night. No, he's not. You drive for the conditions. If that means you can only do 40mph because of the risk of hydroplaning, or because the roads are so wet your stopping distance has increased by a factor of 8 then that means you go slower. Most of the highways here are well lit. Meaning that you can drive them without any headlights at all and still see the road fine. But what really helps more than anything else is that our lane dividers have reflectors built in. Headlights and running lights also severely increase your visibility to other drivers as much as helping your own vision. While your lights may only illuminate a few hundred feet, your lights are visible from THOUSANDS of feet away by other drivers in normal weather. I will be the first to tell people that I do speed. But in poor visibility conditions such as rain, fog, snow, I slow down for visibility, and traction reasons. If I can't SEE a car in front of me, and my visibility is limited to 200ft, then I'm NOT going to be going 70mph (102.6ft/s). In all likely hood I'll be closer to 30mph. 30mph is 44ft/s, which if you are being paranoid thats enough time to react and stop when your visibility is 200ft. Thats about 4 seconds, and if you are ready to stop because you are actively looking for hazzards. I will even go slower. I've done 10 to 15mph on the highway before because of weather. Now, if one is NOT paying attention to the road, then no amount of reaction time can save you because you are being reckless. Read this. http://www.visualexpert.com/Resources/reactiontime.html Expectation Reaction times are greatly affected by whether the driver is alert to the need to brake. I've found it useful to divide alertness into three classes: Expected: the driver is alert and aware of the good possibility that braking will be necessary. This is the absolute best reaction time possible. The best estimate is 0.7 second. Of this, 0.5 is perception and 0.2 is movement, the time required to release the accelerator and to depress the brake pedal. Unexpected: the driver detects a common road signal such as a brake from the car ahead or from a traffic signal. Reaction time is somewhat slower, about 1.25 seconds. This is due to the increase in perception time to over a second with movement time still about 0.2 second. Surprise: the drive encounters a very unusual circumstance, such as a pedestrian or another car crossing the road in the near distance. There is extra time needed to interpret the event and to decide upon response. Reaction time depends to some extent on the distance to the obstacle and whether it is approaching from the side and is first seen in peripheral vision. The best estimate is 1.5 seconds for side incursions and perhaps a few tenths of a second faster for straight-ahead obstacles. Perception time is 1.2 seconds while movement time lengthens to 0.3 second.
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