5.2 Emergency Steering, Leaving the Road & Returning Safely

Sometimes the best stop is no stop at all. The AAMVA manual's emergency section says you can almost always turn to miss an obstacle more quickly than you can stop, and then immediately adds a warning that fits every tank driver: top-heavy vehicles and tractors with multiple trailers may flip over. For tank vehicles, emergency steering has to be done the right way or not at all.

Stop or Steer?

• Stopping is the default when there is room. A straight-line stop keeps the vehicle upright.
• Steering may be the only option when there isn't room to stop, but a quick turn in a loaded or partially loaded tanker can roll it.

Following distance (Section 4.3) and looking 12 to 15 seconds ahead are what keep you out of this choice most of the time.

How to Turn Quickly and Safely

The manual lists the points safe drivers use:

1. Keep both hands on the steering wheel. The best way to have both hands on the wheel in an emergency is to keep them there all the time.
2. Do not apply the brake while you are turning. It is very easy to lock the wheels while turning, and then you may skid out of control. For tank vehicles, the manual adds that steering quickly while braking may roll the vehicle over.
3. Do not turn any more than needed to clear whatever is in your way. The more sharply you turn, the greater the chance of a skid or rollover.
4. Be prepared to counter-steer, turning the wheel back the other way once you have passed the obstacle. Unless you are prepared, you won't do it quickly enough. Think of emergency steering and counter-steering as two parts of one driving action.

Why tank vehicles need extra care

A quick steer pushes liquid toward one side; the counter-steer brings it back the other way. If the counter-steer is jerky or larger than needed, the returning liquid adds to the new sideways force. Use the smallest steering movement that clears the hazard, and brake before or after the maneuver, not during it.

Where to Steer

Leaving the Road

The manual says driving off the road may be less risky than a collision, and most shoulders can support a large vehicle. If you do leave the road:

1. Avoid braking. If possible, don't use the brakes until your speed has dropped to about 20 mph, then brake very gently to avoid skidding on a loose surface.
2. Keep one set of wheels on the pavement, if possible. This helps maintain control.
3. Stay on the shoulder. If the shoulder is clear, stay on it until the vehicle has come to a stop. Signal and check your mirrors before pulling back onto the road.

Returning to the Road

If you are forced back onto the road before you can stop, the manual's method is:

1. Hold the wheel tightly and turn sharply enough to get right back on the road safely.
2. Don't try to edge gradually back on the road. If you do, your tires might grab unexpectedly and you could lose control.
3. When both front tires are on the paved surface, counter-steer immediately.
4. The two turns should be made as a single "steer-counter-steer" move.

A pavement edge can catch the tires if you creep along it, and then they grab and jerk the vehicle across the lane. In a top-heavy tank vehicle, that sudden swerve and the liquid shift that follows can cause a rollover. Staying on a clear shoulder until you stop avoids the problem entirely.

Multi-Trailer Tank Combinations

Some tank operations use doubles, such as a tank semitrailer pulling a second tank trailer. The doubles and triples section of the manual warns:

• Crack-the-whip effect: doubles and triples are more likely to turn over than other combination vehicles. The last trailer in a combination is most likely to turn over.
• Steer gently when pulling trailers.
• Look far ahead so you can slow down or change lanes gradually; doubles must be driven very smoothly to avoid rollover or jackknife.

A steering input that feels mild in the tractor is amplified by the time it reaches the rear trailer. Add surge in partly filled tanks, and quick lane changes become one of the most dangerous maneuvers in tank hauling.

Scenario: A Car Stops Suddenly Ahead

A partly loaded tanker is at 50 mph when a car ahead stops without warning. The left lane is empty (the driver checked mirrors a few seconds ago), and there isn't room to stop.

1. No braking while steering. The driver makes a smooth, limited steering input into the left lane, just enough to clear the car.
2. Immediate counter-steer straightens the rig in the new lane.
3. Only after the vehicle is straight does the driver slow down with steady brake pressure.
4. The driver expects the liquid to shift and keeps inputs small until it settles.

Common Test Traps

• "Brake hard while you swerve." Don't brake while turning.
• "Turn as sharply as possible." Turn no more than needed.
• "Edge back onto the pavement slowly." Turn sharply enough to get back on, then counter-steer when both front tires are on the pavement.
• "When leaving the road, brake right away." Avoid braking until about 20 mph if possible.