Monday, 4 August 2003
|1047 - Pay attention, drivers!|
While procrastinating on some testing I need to do, I ran across this page showing a series of unnerving signs on I-70 approaching Denver from the west. Yow. I've never driven in Colorado, and don't have any plans to do so anytime soon, but I'll definitely watch what I'm doing if I find myself on this piece of highway...
current mood: impressed
current music: Alan Parsons Project - Eye in the Sky
A fully loaded tractor-trailer weighs a hell of a lot, and the braking systems on such a vehicle can easily overheat and start to fail if you're going to fast on a downhill grade like that. The reason for the "stay geared down" sign is that tractor-trailers have 15 or so gears, and if you stay in the lower gears, the truck's engine actually has the torque to be able to keep the truck from accelerating, to an extent; the engine actually is powerful enough that if you stay in gear the engine will keep the drivetrain and the tires running at the same speed and not let the tires get away and run any faster. Of course, this only works in the low gears and at slow speeds, hence the "gear down" warnings, and if you try gearing down to use the engine to slow down after you've started losing control on the downhill and are accelerating, you'll just blow the engine up.
If you don't know what you're doing, your truck will just start, and keep, accelerating if you're not careful, and you'll use up all your brakes trying to slow down, and then your brakes will stop working because they're too hot and you'll just keep accelerating, and then you have to put yourself in the "runaway truck ramp". With no way to control the truck's speed without blowing the engine, you just keep going until you hit the truck ramp. And believe me, a fully-loaded tractor-trailer barrelling down a 6% grade at 70+mph with no working brakes can easily clear a half-mile of gravel before it comes to a stop. Hell, you have to be lucky to be able to stop the vehicle upright, because going through that much gravel at those speeds will have you sliding all over the place.
Driving a truck ain't at all easy, especially cross-country, thanks to passes like that. You think those signs are scary, try reading them while riding in a loaded tractor-trailer. Yeah, you really notice then...