Posted by Chris Davis [108.162.215.49] on Wednesday, April 24, 2019 at 18:51:22 :
In Reply to: Verification helpful ot posted by Bob in N.GA [172.68.65.9] on Tuesday, April 23, 2019 at 09:09:32 :
My dad drove long haul trucks for a living and told me they stop a lot faster empty than loaded. But for this post I thought I'd do a little digging as to how much faster. The linked NHTSA study done in 2011 (using a 1991 Volvo 6x4 tractor, but still new enough to have an antilock brake system) found a 295 foot average loaded stopping distance from 60MPH and a 184 foot average empty stopping distance.
Quite a difference, but current production cars will stop in 120 to 140 feet from 60MPH. What about reaction time though? If you add just ½ a second to realize the truck in front of you is braking... (88fps x .5 = 44ft) you end up with 164 to 184ft stopping distance. That’s cutting it close if the truck in front of you is empty.
I try and give the big rigs plenty of space just for the tire hazard, plus I like to see further down the road whenever possible.