Right Turn With 75 Feet of Triple Trailers
A driver is operating a 75-foot triple-trailer set-three 28-foot pups plus a dolly-on a two-lane road with a 12-foot lane in each direction. The driver needs a right turn into a 20-foot-wide receiving lane. A utility pole is 8 feet from the right edge of the receiving lane, and a car is stopped at the limit line on the left. The driver plans to swing the tractor wide into the left lane to keep the rear trailers off the curb, but an oncoming pickup is approaching 150 feet away at 45 mph. The road is wet, and the rear trailer’s left tires are already 1 foot from the centerline. The driver is running 10 minutes late. A spotter is not available.
1. Plan the turn: where should the tractor and rear trailers be positioned, and why is swinging into the oncoming lane risky?
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Approach the right turn slowly-about 5–10 mph-in the right lane, using the full width of the lane but not crossing the centerline while the pickup is approaching. A 75-foot triple set off-tracks: the rear trailer’s wheels cut inside the tractor’s path, often by several feet in a 90° turn, so the driver needs a wide arc but not an illegal one. If the receiving lane is only 20 feet wide and the pole is 8 feet from the edge, the driver should stop before the turn and wait for the oncoming pickup to clear, then use the left side of the right lane to begin the turn, keeping the rear trailer’s right side away from the pole. Swinging into the oncoming lane is risky because the pickup is closing at 45 mph, the road is wet, and the rear trailer can block the lane longer than expected. If a safe arc cannot be made without crossing the centerline, the driver should choose another route or use a spotter.
2. If the driver begins the turn and sees the rear trailer tracking toward the utility pole, what should the driver do?
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Stop immediately rather than continuing and jerking the wheel. Continuing a tight turn will pull the rear trailer farther inside and can strike the pole; braking hard mid-turn can also cause the trailers to skid or jackknife on the wet road. Stop with the set straight enough to hold position, set the parking brake, and assess. If the rear trailer has not hit the pole, the driver may need to back up slightly to create a wider arc-only with a spotter and after checking mirrors and surrounding traffic-or wait for help. Do not use the curb or pole as a guide. After clearing, complete the turn slowly, watching the rear trailer’s tires in the mirrors and keeping the left side clear of the stopped car. If the driver cannot see the rear trailer’s path, a spotter should guide the turn.
3. How should the 10-minute delay affect the driver’s decisions?
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The delay should not change the safety decision. Rushing a 75-foot triple into a tight right turn increases the chance of clipping the pole, crossing the centerline, or stopping in the path of the oncoming pickup. The driver should treat the appointment as secondary to the space needed for the rear trailer. If waiting for traffic, backing for a wider arc, or taking another route costs time, that is the correct trade. The driver should also consider calling dispatch to report the delay rather than trying to make up time in the turn. A late arrival is cheaper than a separated set, a sideswipe, or a pole strike.