5.4 Multilane Highways, Expressway Merging, Railroad Crossings & Complex Intersections

Higher Speed Requires Earlier Decisions

Expressways combine high speed, heavy traffic, limited access, and short decision windows. Complex intersections and railroad crossings create different conflicts but demand the same habits: identify the control early, choose the lane in advance, preserve an escape path, and never enter a space that cannot be cleared.

Entering an expressway

Before the trip, know the entrance and exit. On an ordinary acceleration lane, search expressway traffic while using the ramp to approach an appropriate merging speed. Signal and look over the shoulder because mirrors leave blind areas. Traffic already on the expressway has the right-of-way; adjust speed to enter a usable gap without forcing another driver to brake.

Do not stop at the end of a normal acceleration lane unless traffic or a control device makes it necessary. If a very short entrance lane does not allow safe acceleration, the Driver's Manual says stopping for a large space can be the safest method. That is an exception based on the ramp, not a general merging technique.

After merging, establish space and cancel the signal. When practical, an expressway driver can move from the right lane to give entering traffic more room, but only after a safe lane-change search.

Lane changes and exits

Use mirrors, signal, direct blind-area check, speed adjustment, and a smooth lateral movement. Avoid traveling beside another vehicle with no escape path. Make one lane change at a time and recheck before the next.

Read destination signs early and enter the exit lane in time. Signal at least 100 feet before reaching the ramp. Reduce speed on the ramp, where a lower limit and sharper curve often apply, rather than slowing sharply in the through lane. After leaving, check the speedometer; freeway speed can make an ordinary road speed feel unusually slow.

If an exit is missed, continue to the next exit. Never back on a ramp, stop in a gore area, or cross a median. On limited-access highways, U-turns are prohibited except where an authorized connection and control permit them.

Railroad crossings

Approach prepared to stop. Obey flashing signals, bells, gates, flaggers, and trains. Never drive around a gate that is moving or down. At a passive crossbuck, look and listen and yield if a train is close enough to be a hazard. Confirm the number of tracks and make sure no second train is approaching.

Do not enter until there is enough room to clear all tracks. Some buses and vehicles carrying hazardous cargo must stop at crossings; stay behind and anticipate that requirement.

If a vehicle stalls on tracks, get everyone out immediately and move away from the tracks. Use the Emergency Notification System sign to contact the railroad and call emergency services. If a train approaches, move away from the tracks toward the general direction from which the train is coming so collision debris travels away from the escape path.

Complex intersections

Follow lane-use arrows and signs. Choose the lane before solid channelizing lines. Search for pedestrians, bicycles, oncoming turns, and vehicles running a late signal. Do not enter an intersection if traffic ahead prevents clearing it, even with a green signal.

Teaching progression

Begin with diagrams and lower-volume multilane roads. Rehearse a spoken merge plan before using an expressway. The instructor should choose a route with enough ramp length and avoid giving a last-second direction. Evaluate search timing and gap choice, not merely whether the vehicle ended in the intended lane.

Gap analysis

Before the merge point, require a target gap and backup gap. Compare speed with both the lead and following vehicles rather than staring at the end of the lane. At a railroad crossing, use the same two-part decision: confirm that no train or control prohibits crossing, then confirm space beyond the farthest rail for the entire vehicle.

Preserve an expressway escape plan

Before entering the ramp, the student should know whether the entrance has an acceleration lane and where it ends. In the lane, identify a primary gap and a backup gap while adjusting speed. Looking only at the vehicle ahead can hide a fast-closing vehicle beside or behind; looking only over the shoulder can allow the ramp path to change unnoticed. Alternate the search while holding a stable path.

If no safe gap develops, respond to the actual lane design. A normal acceleration lane is intended for speed adjustment and merging, so an unnecessary stop at its end creates a difficult high-speed entry. A short entrance with no usable acceleration area may require waiting for a large opening as the Driver's Manual explains. The instructor should preview that distinction before the student reaches the decision point.

After a merge, rebuild following space rather than immediately making another lane change. For an exit, finish the move into the exit lane before slowing for the ramp unless traffic or controls require otherwise.

At railroad crossings, separate two decisions: no train, signal, gate, or flagger prohibits entry; and enough open space exists beyond the farthest rail for the entire vehicle. A clear first track is not enough when there are multiple tracks or stopped traffic beyond them.