Which statement best reflects stopping distance for a 55 mph truck with air brakes under ideal conditions?

Which statement best reflects stopping distance for a 55 mph truck with air brakes under ideal conditions?

• A. Less than 100 feet
• B. Between 200 and 300 feet
• C. More than 300 feet
• D. About 350 feet

Answer: (C)

Stopping distance grows with speed, and for a heavy truck with air brakes it stays long even on dry pavement. The total stopping distance is the sum of what it takes the driver to react and the distance the truck needs to stop once braking begins. At 55 mph, a typical reaction time puts you about eighty feet behind the point where you notice the hazard and start braking. The braking distance for a loaded tractor-trailer with air brakes is much longer than for a car because of the truck’s weight and the way air brakes operate, which adds a brief delay as air pressure builds and brakes apply. Put together, these factors push the total stopping distance beyond 300 feet, often into the mid-300s under ideal conditions. So, the best description is that stopping distance is more than 300 feet.

Stopping distance grows with speed, and for a heavy truck with air brakes it stays long even on dry pavement. The total stopping distance is the sum of what it takes the driver to react and the distance the truck needs to stop once braking begins. At 55 mph, a typical reaction time puts you about eighty feet behind the point where you notice the hazard and start braking. The braking distance for a loaded tractor-trailer with air brakes is much longer than for a car because of the truck’s weight and the way air brakes operate, which adds a brief delay as air pressure builds and brakes apply. Put together, these factors push the total stopping distance beyond 300 feet, often into the mid-300s under ideal conditions. So, the best description is that stopping distance is more than 300 feet.