Managing Space and Speed Flashcards

At night, a CMV driver's speed should be adjusted so that:

Answer: The vehicle can stop within the distance illuminated by headlights

Driving within the headlight range means the driver can stop before reaching any hazard that becomes visible in the lights.

What effect does a full load of loose gravel have on a CMV's braking distance compared to an empty truck?

Answer: Braking distance is longer because the vehicle has greater momentum

Greater vehicle weight means greater momentum, requiring more distance for the brakes to bring the vehicle to a stop.

A CMV traveling at 65 mph has how much more stopping distance than the same truck traveling at 45 mph?

Answer: About twice the stopping distance

Stopping distance increases with the square of speed, so going from 45 to 65 mph roughly doubles the distance needed to stop.

When driving through a work zone with reduced lane width, a CMV driver should:

Answer: Increase following distance and reduce speed

Reduced lane widths leave less margin for error, so increasing following distance and reducing speed gives more reaction time.

What is the danger of 'over-braking' on a slippery surface?

Answer: It can cause wheels to lock up, leading to loss of steering control

Applying brakes too hard on slippery pavement can lock the wheels, causing the vehicle to slide straight regardless of steering input.

On a long upgrade, a heavily loaded CMV may slow significantly. What is the safest response?

Answer: Downshift to maintain speed and engine power

Downshifting before losing too much speed gives the engine the mechanical advantage to maintain controlled forward progress up the grade.

How does road camber (the slope from the center to the edges of the road) affect a CMV in a curve?

Answer: Negative camber (banked away from the turn) increases rollover risk

A road that slopes away from the direction of the turn (negative or adverse camber) reduces the effective friction and increases rollover risk for high-CG vehicles.