The US National Transportation Safety Board (NTSB) has released its report on the collision between the warship John S McCain and chemical tanker Alnic MC which resulted in the death of 10 navy sailors. As a result of the NTSB findings, touchscreen throttles are to be replaced with mechanical controls on US Navy vessels
Background to the incident from the report
On 21 August 2017, US Navy destroyer John S McCain was overtaking Liberian-flagged tanker Alnic MC while both vessels were transiting the westbound lane in the Middle Channel passage of the Singapore Strait Traffic Separation Scheme. The destroyer crew had a perceived loss of steering, and, while the crew attempted to regain control of the vessel, John S McCain unintentionally turned to port into the path of Alnic MC. At 0524, the vessels collided. As a result of the collision, 10 John S McCain sailors died, 48 were injured, and the vessel sustained over US$100M in damage. No one was injured on Alnic MC, and the vessel sustained about US$225,000 in damage. There was no reported pollution.
Why did John S McCain veer into Alnic MC?
The steering and throttles on John S McCain were operated on the bridge by touchscreens. The advantage was allowing throttle and steering controls to be sent to different helming stations on the bridge – the disadvantage being that this could be done by accident, too.
“The NTSB concludes that the perceived loss of steering by the John S McCain helmsman was due to the unintentional transfer of steering control from the helm station to the lee helm station. The report noted that without the tactile feel of moving a mechanical control and the lack of visibility of the position of a mechanical control the operator can miss important feedback and verification." The NTSB continued “Mechanical throttles are used in aviation and on most vessels still operating in the Navy. They are often preferred over touchscreen displays as they provide both immediate and tactile feedback to the operator.”
The NTSB report stated “The NTSB concludes that the design of the John S McCain’s touchscreen steering and thrust control system increased the likelihood of the operator errors that led to the collision. Therefore, the NTSB recommends the Navy ensure that the modernisation of complex systems, such as steering and control systems within the IBNS, incorporates the design principles set forth in ASTM International Standard F1166,” which is to introduce mechanical systems.
The report goes into great detail of the actions and inactions of the naval crew and its reading would be useful for tanker operators to be aware of the likely activities taking place on the bridge of a warship as it approaches a tanker.
The report can be found here.
Tanker safety is one of the issues that will be discussed at the Tanker Shipping & Trade Conference, Awards & Exhibition, London: 26-27 November.