Right Turn from a Two-Lane Road into a Narrow Street
You are driving a set of doubles-a 53-foot lead trailer and a 53-foot rear trailer-north on a two-lane road with 12-foot lanes. You need to turn right onto a 24-foot-wide street. The curb return is tight, about 25 feet, and there is a utility pole on the left corner. Parked cars line the right side of the new street, and oncoming traffic is steady. Your speed is 20 mph as you approach the stop line. In your right mirror, the rear trailer's tires appear to be tracking about 8 feet inside the curb line. A car behind you is close and honking. You have a spotter available, but he is standing on the left side of the intersection, out of your mirror view.
1. How should you set up and execute this turn? Include where to position the tractor, when to start steering, and what to watch in the mirrors.
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Set up wide before the turn: move toward the left side of your lane, and use the opposing lane only if it is clear and legal. With steady oncoming traffic, wait at the stop line until you have room; do not swing into an occupied lane. The rear trailer cuts the corner, so the wider your approach, the more room the trailer has.
Start steering later than you would in a car, and keep the tractor close to the centerline of the new street so the rear trailer can swing inside. Watch the right mirror for the rear trailer's tires and the left mirror for the utility pole and oncoming traffic. Keep your speed very low; 20 mph is too fast for this geometry. If the rear trailer's tires approach the curb or the parked cars, stop and reassess rather than continuing and hoping. The car behind you is irrelevant to the physics; let it wait.
2. The rear trailer's tires are 8 feet inside the curb line. What does that tell you, and what are your options if the trailer continues to cut the corner?
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It tells me the rear trailer is off-tracking heavily and is aimed at the curb, the utility pole, or the parked cars. Eight feet is not a small correction; it means the turn is too tight for the current setup. I would stop before the trailer reaches the curb.
Options:
- Back up if the area behind is clear and a spotter can guide me. Backing a set of doubles is difficult, so this must be done slowly with mirrors and a spotter.
- Take a wider approach if traffic clears, possibly using more of the opposing lane.
- Ask the spotter to hold traffic while I adjust.
- If the geometry cannot be made safely, choose another route. A damaged trailer, pole, or parked car is worse than a detour.
Continuing the turn while the trailer is already 8 feet inside the curb is how right-turn squeeze accidents happen.
3. Why is a spotter on the left side a problem, and how would you use him safely?
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A spotter I cannot see in a mirror cannot guide me. He may think he is signaling, but I would be blind to it. Before moving, I would agree on hand signals or use a radio, and position him where he is visible in my left or right mirror and clear of the trailer path. He should not stand between the trailers or near the curb where the rear trailer will track.
During the turn, I would use him mainly to hold traffic and to watch the left side and the utility pole while I watch the right mirror. If radio contact is lost, I stop. A spotter is an extra set of eyes, not a substitute for my own mirror checks.