Visual Search, Speed & Space Management Practice Test
Question 1 of 16
You are driving a loaded tractor-trailer at 55 mph on a dry road. About how many seconds of following distance should you keep from the vehicle ahead?
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Not quite.
Wrong. The 1-second-per-10-feet rule by itself only applies at speeds at or below 40 mph. Above 40 mph you must add one more second to make up for the greater stopping distance.
The correct answer is B: At least 1 second for every 10 feet of vehicle length, plus 1 extra second at speeds over 40 mph.
49 CFR 383.111(a) (Space Management)
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Correct!
Correct. The AAMVA CDL Manual (Section 2) and 49 CFR 383.111(a) safe-space-management topic both call for 1 second of following distance per 10 feet of overall vehicle length at speeds under 40 mph, and one additional second whenever your speed is over 40 mph.
49 CFR 383.111(a) (Space Management)
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Not quite.
Wrong. A flat 3-second rule is the passenger-vehicle guideline, not the commercial vehicle standard, and it ignores vehicle length entirely.
The correct answer is B: At least 1 second for every 10 feet of vehicle length, plus 1 extra second at speeds over 40 mph.
49 CFR 383.111(a) (Space Management)
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Not quite.
Wrong. There is no flat 8-second federal or AAMVA standard; the correct method scales with vehicle length and adds a second over 40 mph.
The correct answer is B: At least 1 second for every 10 feet of vehicle length, plus 1 extra second at speeds over 40 mph.