Examkin

Question

Difficulty: MediumSpace Ahead and Following Distance

Under ideal weather and dry road conditions, a commercial driver operates a 45-foot45\text{-foot} flatbed truck at a steady cruising speed of 52 mph52\text{ mph}. According to standard commercial vehicle safety guidelines, what is the minimum recommended following distance, in seconds, that the driver should maintain behind the vehicle ahead?

Answer: 5.5 seconds

Answer

5.5 seconds
According to the official CDL space management rule, a driver must allow at least 1 second for each 10 feet of vehicle length at speeds below 40 mph, plus an additional 1 second when traveling at or above 40 mph. For a 45-foot vehicle traveling at 52 mph, the base requirement is 4.5 seconds plus 1 second for speed, totaling 5.5 seconds.

Step-by-Step Solution

1
Calculate base following distance interval for vehicle length
4.5 seconds
The standard CDL formula requires 1 second of following distance for each 10 feet of vehicle length.
2
Determine speed adjustment requirement
+1.0 second
For vehicle operating speeds at or above 40 mph, safety regulations require adding 1 additional second to the following interval.
3
Calculate total minimum following distance in seconds
5.5 seconds
Adding the 4.5 seconds length requirement to the 1.0 second speed increment yields the minimum safe cushion of 5.5 seconds.

Key Concept

CDL Following Distance Formula
Estimated Time:1m 0s
Rate this question

Topics

Space Ahead and Following Distance

More questions from this topic