A malfunction in the steering control system of the multi-purpose carrier BBC Africa caused the vessel to collide with the bulk carrier Common Faith in the Houston Ship Channel on August 25, 2023, the National Transportation Safety Board (NTSB) said in its findings released Thursday.
The incident happened while the BBC Africa was departing the channel. The vessel suddenly lost steering control and struck the Common Faith, which was moored at the time. No one was injured, and there was no pollution reported, but the combined damage to the two vessels was estimated at $1.1 million.
The crew told investigators that no problems were detected in the steering system during the pre-departure checks. At first, the ship was responding normally to steering commands from the port bridge wing. But when the control was switched to the center helm using the “in-command” (FU) button, the rudder unexpectedly turned hard to port. This movement was opposite to both the pilot’s orders and the helmsman’s actions.
The chief officer attempted several times to restore primary steering by pressing the FU button again, but all attempts failed. About a minute later, the master managed to regain control using the emergency override function. By then, it was too late to maneuver the vessel in time to prevent the collision.
Investigators stated that the crew’s delayed reaction in activating emergency steering procedures contributed to the accident.
After the incident, technicians from the steering system manufacturer and NTSB officials examined the mechanical and electrical parts of the three control stations and panels. Based on the rudder’s unexpected movements and testing after the crash, the failure was traced to a faulty micro switch in the bridge wing tiller.
The NTSB said that steering system failures can quickly lead to accidents, especially in channels where other vessels, shallow waters, or objects are nearby. The agency stressed that crews must respond immediately in such situations. It also pointed out that regular training and scenario-based drills for both bridge and engine teams are crucial to ensure prompt action in emergencies.
Following the collision, the ship operator replaced three key components that may have contributed to the steering failure: the power supply transformer inside the control cabinet behind the main bridge, the port bridge wing tiller, and the push-button relays that transfer “in command” control.
Meanwhile, the steering gear manufacturer issued a safety bulletin addressing switch failures in bridge wing tillers. The bulletin warned that micro switch failures could result in unintended rudder movements, similar to what occurred on the BBC Africa.
For the full report, click Marine Investigation Report 25-33
Reference: NTSB
Source: Maritime Shipping News