Safe driving with tank vehicles (curves, braking, skids, speed)
What this domain tests
Safe driving with tank vehicles tests speed selection, curve entry, braking, skid control, and space management. The exam expects you to apply tanker-specific limits, not standard car habits.
Core rules
- Slow down before a curve, not in it. Brake while the vehicle is straight, then use a gentle, steady throttle through the curve. Hard braking in a curve adds surge and can trigger a rollover.
- Obey advisory speeds as your upper limit. A tanker’s rollover threshold is lower than a van’s or flatbed’s.
- Increase following distance. A loaded tanker needs more stopping distance, and liquid surge lengthens it further.
- On downgrades, select a low gear before the descent and use engine braking where permitted. Do not ride the service brakes.
- If a rear skid starts, release the brakes to restore wheel rotation, steer in the direction you want the front to go, and straighten as traction returns. Avoid overcorrection.
Worked example
A curve is posted at 25 mph. You enter at 40 mph. The sideways force needed to hold the curve rises roughly with the square of speed: (40/25)² = 2.56, so you are asking for about 2.5 times the force compared with 25 mph. In a tanker with a high center of gravity, that can exceed tire grip and roll the vehicle. Reasoning: the safe entry speed is set before the curve, not adjusted after the tank leans.
Traps
Do not brake hard mid-curve. Do not use a high gear on a steep downgrade. Do not “steer out of” a skid with a big counter-steer. Do not treat an advisory speed as irrelevant in good weather.