What Happened
What Happened
On November 12, 2023, about 0552 local time, the towing vessel Cindy B was pushing the loaded deck barge St. John upbound on the Columbia River at mile 53 near Clatskanie, Oregon, when the tow gradually moved to starboard out of the navigation channel and struck the Port Westward Beaver Dock. None of the three crewmembers aboard the Cindy B were injured. During the cleanup, about 2 gallons of renewable diesel fuel leaked onto the dock from a damaged pipe on the dock, with about 1 gallon going into the river; a portion of the spilled fuel was recovered. Damage to the St. John and the Beaver Dock was estimated to be about $6 million.
What We Found
What We Found
We determined that the probable cause of the contact of the Cindy B tow with the Port Westward Beaver Dock was the deckhand falling asleep at the helm due to fatigue that he did not perceive, which occurred during a night watch, at a low point in his circadian rhythm, and following a change in his awake/sleep cycle. Contributing to the casualty was the pilothouse alerter system not alarming to wake the incapacitated deckhand at the helm because a swinging VHF radio microphone in the motion sensors’ field of view defeated the system.
What We Recommended
Transitioning from Daytime to Nighttime Work
Disturbances in awake/sleep cycles caused by transitioning from daytime to nighttime watches or shifts result in increased accidents and occupational mistakes. Although the impacts of these awake/sleep cycle disturbances cannot be fully mitigated, they can be reduced by tools such as pilothouse alerter systems and by allowing longer downtime between watches/shifts.
Using Pilothouse Alerter Systems
A pilothouse alerter, when used as intended, is an effective tool that can help ensure that a crewmember remains awake and vigilant while on duty. Established procedures for the operation and use of the system, to include measures to ensure the system cannot be unintentionally reset, help ensure that it operates as designed.
