​We determined that the probable cause of the contact of the Mackenzie Rose tow with the Norfolk and Portsmouth Belt Line Railroad Bridge was a loss of control of the tow by the mate at the helm, possibly due to his error in switching from autopilot to hand steering or impairment by fatigue.​

​​Safe Navigation with Autopilot

Navigating in channels and harbors requires quicker reaction times due to traffic, currents encountered, and frequent course changes, and more rudder due to slower speeds. Therefore, autopilot use is often discouraged or prohibited in a harbor entrance or narrow channel. If autopilot must be used, it is critical that vessel operators be fully trained in all features and functions of a vessel’s systems so that they can quickly adjust the modes of the autopilot system or disengage the autopilot to return to hand steering as needed.