The Right Turn That Leaves No Room
You are driving a 53-foot van trailer with a gross combination weight of 78,000 lb. At a stop sign in a small Kansas town, you need to make a right turn onto a 24-foot-wide two-lane road. The curb radius is 20 feet. A utility pole stands 6 feet from the curb on the far side of the turn, and a pickup is waiting at the stop line on the cross street. Your trailer’s rear wheels are 8 feet from the right curb as you sit at the stop sign. The road you are leaving is 40 feet wide; the cross street has one lane each way. Traffic is light, but the pickup has crept forward about 2 feet. Your tractor has a 10-speed manual transmission and a sliding fifth wheel set in the middle position.
1. Where should the tractor be positioned before the turn and why?
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The tractor should approach in the right lane but may need to move left within the lane - or use more of the road if it is legal and clear - to keep the trailer’s rear wheels from hitting the curb or the utility pole. The reason is off-tracking: the rear wheels of a long trailer follow a path inside the tractor’s path. With a 53-foot trailer, that cut-in is large, so starting tight to the right curb almost guarantees the trailer will track over the curb. The driver should not swing blindly into an oncoming lane; check mirrors and oncoming traffic first. The goal is a smooth, slow arc that keeps the trailer wheels close to - but not over - the curb, while leaving room for the pole.
2. How should the driver monitor the trailer’s rear wheels, and what does off-tracking mean in this turn?
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The driver should use both mirrors, especially the right mirror, and watch the trailer’s rear wheels against the curb and pole throughout the turn. Off-tracking means the trailer’s rear wheels do not follow the tractor’s front wheels; they cut the corner. In a 90-degree right turn with a 20-foot curb radius, the trailer’s rear wheels may be several feet inside the path the driver sees from the cab. If the wheels approach the curb or the pole, the driver should stop and reset rather than continue and hope. A spotter is useful if available, but the driver remains responsible. Slow speed and a wide initial setup are what create the room the trailer needs.
3. If the pickup creeps forward and blocks part of your path, what is the safe action?
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Stop and hold your position. Do not wave the pickup through, and do not commit to a turn you cannot complete. The pickup is in a vulnerable position, and a 78,000-lb combination cannot stop or change path quickly once the turn is started. If the pickup blocks the lane, wait for it to clear or for another driver to direct traffic; if necessary, back up only with a spotter and only after making sure the area behind is clear. The safe choice is to give up the “right of way” rather than crowd the curb, hit the pole, or force the pickup into a bad position. Patience is cheaper than a sideswipe or a curb strike.