Right Turn from a 12-Foot Lane with 104 Feet of Triple Behind You
You are pulling a triple out of a rail yard in Allentown: a 20-foot tractor and three 28-foot pups with two converter dollies, about 104 feet bumper to bumper. At 06:40 you need to turn right from a four-lane road onto a two-lane street. The right-turn lane is 12 feet wide; the corner has a 20-foot curb return, a traffic signal pole about 6 feet off the curb, and a fire hydrant on the corner. A car is waiting in the cross street's left-turn lane, and two cars are behind you. In your right mirror the last pup's right rear tires are still in the right lane, and you plan to start the turn at about 5 mph. The street you are turning into has a 35-mph limit and a bike lane along its right edge.
1. Where do you position the tractor before starting the turn, and why does the length of the set drive that choice?
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Start from the left side of your lane, not the center.
Every pivot in a triple adds off-tracking: the tractor, each of the two dollies, and each pup. The last pup's tires can track several feet inside the path of the front tires - with 104 feet of combination and a 20-foot curb return, it will be well inside the curb line if you turn from the middle of a 12-foot lane.
- Use the full width of the right lane first.
- If the geometry still does not fit, using part of the lane to your left is acceptable only when it is clear and legal. Crossing the center line into oncoming traffic is not an option, even to save a curb.
- Check the left mirror before you move left: the nose swings left while the tail swings right, and both are outside the path a car driver expects.
- Size the corner before you commit: the pole 6 feet off the curb and the hydrant are the obstacles your tail will reach first.
Often the professional answer is to decide before the intersection that this turn does not fit and take another route. Once committed, you cannot back a triple out of it.
2. Describe your speed and what you watch during the turn, and what you do if the last pup's tires drift toward the curb.
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Speed: walking pace - 5 mph or less - and steady. Avoid stopping mid-turn if you can, because a triple stopped with its tail across a lane is hard to restart without the tail wandering.
Watch:
- Right mirror: the last pup's right rear tires and the curb. Keep 2-3 feet of clearance.
- Left mirror: the tail of the last pup swinging toward the oncoming lane.
- The dollies: if one is being dragged sideways, the pintle area strains and that trailer stops tracking its own path.
If the tires drift toward the curb, stop. Do not accelerate to pull it around - speed makes the tail cut deeper and turns a near miss into a hard curb strike. Because you must never back a triple, your only safe move once committed is to stop and hold, then get someone to control traffic while you work out the rest of the turn.
Steering smoothly matters as much as speed: jerking the wheel whips the tail of the last pup.
3. If the last pup's tires do hit the curb, what is the real risk, and what should you have done before starting the turn?
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A curb strike on a triple is not cosmetic:
- Tire and wheel damage on a pup whose tire is carrying roughly 10,000 pounds.
- The dolly behind is dragged sideways. The pintle, drawbar eye, and safety chains take the load, and low-routed air lines can be crushed - which can set the trailer's spring brakes or leave you with a dragging brake.
- The tail can reach the pole or the hydrant, and the bike lane puts a cyclist exactly where the tail swings.
What you should have done: sized the turn before entering it. A 104-foot set turning into a two-lane street off a 12-foot lane with a 20-foot curb return will not make it cleanly. The correct call was a different route, a wider entry taken legally, or a spotter holding traffic while you use both lanes. The one thing you cannot do after the fact is back up.