Right Turn With a 53-Foot Trailer on a Narrow Somerville Street
You are driving a 53-foot trailer westbound on a two-lane one-way street in Somerville, approaching a right turn onto a two-way cross street. Your trailer's rear wheels track about 8 feet inside the tractor's path. The right lane is blocked 100 feet before the corner by a delivery van with flashers on. A cyclist is riding behind you in the right lane. The cross street has a 20-foot curb radius and parked cars on both sides. A pedestrian is waiting at the corner. The light is green, and traffic behind you is close. You need to turn right without hitting the van, the cyclist, the parked cars, or the curb. The street is posted 'No trucks over 30 feet,' but your company route sheet lists this as a legal turn.
1. How should you position the tractor and trailer for this right turn, and what must you do about the blocked right lane?
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Use the one-way street to your advantage, but do not force the turn. If the left lane is clear and legal, move left before the corner to increase the turning radius and keep the trailer off the curb; do not swing into parked cars or the crosswalk. The blocked right lane means you cannot squeeze between the van and the curb. Wait for the van to move, or use the left lane only if you can do so without crossing the center line of the cross street or hitting anything.
Keep the trailer wheels close to the curb after the tractor starts the turn, and watch the trailer in the convex mirrors. If the geometry will not work, do not turn; take another route. The 'No trucks over 30 feet' sign is also a warning that the route sheet may be wrong.
2. The light turns green and the cyclist moves up on your right as you begin the turn. What do you do?
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Stop and let the cyclist clear. A cyclist coming up on your right is in the most dangerous blind spot during a right turn. If you continue, the trailer can cut across the cyclist's path and crush them against the curb. Keep the tractor straight, check the right convex mirror, and wait until the cyclist has either passed completely or stopped behind you.
Do not wave them through and do not accelerate to beat them. If they are beside the trailer and you cannot see them, do not move until a spotter or the mirror confirms the area is clear. The green light does not give you priority over a vulnerable road user.
3. What if the trailer's rear wheels are 2 feet from the curb and a parked car is 8 feet into the cross street? Can you complete the turn, or what is the decision?
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Stop and reassess rather than forcing the turn. A 53-foot trailer with about 8 feet of off-tracking needs more than a 20-foot curb radius when a parked car narrows the cross street. If the trailer's rear wheels are already 2 feet from the curb and the car is 8 feet into the street, completing the turn risks hitting the car, the curb, or both.
Do not back up in the intersection unless you have a spotter and it is legal and safe. The better choice is to abort the turn, continue straight, and take a route that fits the vehicle. If you must wait for the car to move, stop before the crosswalk and put on your hazards. A route sheet does not override physical clearance or a posted restriction.