What should a driver do if a trailer begins to swerve or whip unreasonably?

When a trailer begins to swerve or whip unreasonably, the best course of action is to slow down and come to a halt. Reducing speed is crucial in this scenario as it helps to regain control over the trailer. Trailers can sway due to a variety of factors, such as wind, road conditions, or improper loading. By decelerating, the driver decreases the lateral forces acting on the trailer, allowing it to stabilize. Coming to a stop ensures that the driver can reassess the situation, check for any potential issues (like load distribution), and prevent further loss of control.

Accelerating to regain control, turning the steering wheel sharply, or maintaining speed while waiting for the swerve to stop can exacerbate the situation. These actions could lead to more severe maneuverability issues or even cause the trailer to jackknife, resulting in a higher likelihood of an accident. Therefore, a gradual and controlled reduction in speed is the safest response to regain stability.