Right Turn With a Double-Bottom in Downtown Traffic
At 14:10 you are driving a 63-foot double-bottom combination, tractor, 28-foot pup, converter dolly, and 28-foot pup, through downtown Columbus. You need to turn right from a three-lane one-way street onto a two-lane one-way street. The curb radius is about 25 feet, a fire hydrant sits 10 feet from the corner, and a pedestrian island narrows the mouth of the turn. Traffic is heavy, and a delivery van is stopped in the right lane 40 feet before the corner. Your right convex mirror shows the rear pup tracking inside the curb line. You are empty in the first pup and loaded to 8,000 lb in the second. The light turns green. You must complete the turn without hitting the curb, hydrant, or van.
1. How should you set up and execute the right turn, given the short curb radius and the rear pup's offtracking?
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Do not squeeze between the stopped van and the curb. Stop behind the van or make a legal lane change early enough to approach the corner from the rightmost available lane. For the turn, keep the tractor farther left within the lane, without crossing the centerline or entering an occupied lane, so the rear pup has room to cut the corner. Start the turn slowly, about 5 to 10 mph, and delay the steering input until the tractor is well into the intersection. Watch the right convex mirror continuously; the rear pup tracks inside the tractor's path, so its tires will aim closer to the hydrant and curb than the tractor's tires. If the rear pup approaches the curb, stop before contact and reassess; do not continue and hope it clears.
2. The rear pup's tires are within 1 foot of the curb and still moving inward. What are your options, and which is safest?
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The safest immediate action is to stop before the tire contacts the curb. Continuing the turn will likely drag the rear pup over the curb or into the hydrant. Backing a double-bottom in live downtown traffic is high risk and may not be legal from that position, so avoid it unless a spotter and clear traffic make it safe. If you have not completed the turn, straighten the tractor slightly to widen the rear pup's path, but only if you can do so without hitting the van, opposing traffic, or the island. Otherwise hold position and wait for a spotter or police/traffic control. A curb strike can damage tires, wheels, and the dolly, and a hydrant strike is an emergency. The safe choice is to stop and reset rather than force the turn.
3. What would you do if you find the turn cannot be made without entering the opposing lane?
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Do not enter the opposing lane. With a 25-foot curb radius and a 63-foot combination, the geometry may require more room than this intersection gives. If no legal path exists, stop before committing, check for a spotter, and consider waiting for traffic to clear so you can use more of the available width legally. If the intersection still cannot accommodate the combination, take a different route or ask for traffic control. Forcing the turn risks a head-on conflict, curb damage, or a jackknife recovery in a crowded intersection. The correct judgement is to reject the turn before the vehicle is committed, not to complete it and create a hazard.