NTSB Releases Its Analysis of the USS John S McCain Collision

The U.S. National Transportation Safety Board (NTSB) has released its analysis of the August 21, 2017, collision between the USS John S McCain and the tanker Alnic MC, stating it was caused by insufficient training, inadequate bridge operating procedures and a lack of operational oversight.

10 sailors aboard the John S McCain died in the accident and 48 were injured when the ships collided in the Middle Channel passage of the Singapore Strait Traffic Separation Scheme. The John S McCain, an Arleigh Burke-class destroyer with a crew of 280, and the Alnic MC, a Liberian-flagged chemical tanker carrying a partial load of cargo with a crew of 24, were transiting towards Singapore in the westbound lane of the Singapore Strait Traffic Separation Scheme. 

The Singapore Strait is one of the busiest waterways in the world, with more than 83,700 vessels of more than 300 gross tons transiting the strait in 2016.

The NTSB determined the probable cause of the collision was a lack of effective operational oversight of the destroyer by the U.S. Navy, which resulted in insufficient training and inadequate bridge operating procedures. Contributing to the accident were the John S McCain bridge team’s loss of situation awareness and failure to follow loss of steering emergency procedures, including the requirement to inform nearby vessel traffic of their perceived loss of steering. Also contributing to the accident was the operation of the steering system in backup manual mode, which allowed for an unintentional, unilateral transfer of steering control.

As the John S McCain entered the Singapore Strait, steering and thrust were being controlled by a single watchstander – the helmsman – from the helm station. The commanding officer directed the lee helm station be manned as well, and the crew took actions intended to transfer propeller thrust control from the helm to the lee helm station. The NTSB concluded that during the process of shifting thrust control, a John S McCain watchstander unintentionally transferred control of steering from the helm to the lee helm station which resulted in a perceived loss of steering by the John S. McCain’s helmsman. However, steering control was available at all times in the accident sequence. The unintentional transfer was possible because the system was being operated in backup manual mode, which removed a safeguard against inadvertent transfer of steering control.

The NTSB also concluded in its report that the inability to maintain course due to a perceived loss of steering, the mismatch of port and starboard throttles producing an unbalanced thrust, and a brief but significant port rudder input from after steering combined to bring the John S McCain into the path of the Alnic MC. The decision to change the configuration of the John S McCain’s critical controls while the destroyer was in close proximity to other vessels increased the risk of an accident.

John S McCain crewmembers indicated during interviews that in the days preceding the accident, the steering system had alarmed for several minor faults, but none that resulted in a loss of steering. The Commanding Officer (CO) did not indicate that this was a factor in his decision to operate in backup manual mode. Rather, he told investigators that backup manual mode provided a “more direct form of communication between the steering and SCC [Ship Control Console].” 

He further stated, “We were more comfortable in that configuration” and noted that COs of other ships that he had talked to also preferred to operate in backup manual mode in certain situations. Although the written guidance stated that the normal mode of operation was computer-assisted manual mode, the use of backup manual mode was common on board the John S McCain and other similarly equipped ships. However, operating in backup manual mode removed one safeguard against an inadvertent transfer of steering control: the requirement for two watchstanders to take action to complete the transfer.

 The John S McCain crew’s inability to effectively respond to the emergency calls into question the Navy’s assessment and certification process, states the report. Additionally, despite significant research and universal standards in place within the marine industry, the Navy had no fatigue mitigation program or standards for ensuring crewmembers aboard the John S McCain had adequate rest. The NTSB concluded that the Navy failed to provide effective oversight of the John S McCain in the areas of bridge operating procedures, crew training and fatigue mitigation.

Based upon its investigation of the collision, the NTSB issued seven safety recommendations to the U.S. Navy seeking:

•  Issuance of permanent guidance directing destroyers equipped with the Integrated Bridge and Navigation System to operate in computer-assisted steering modes, except during an emergency.

•  Issuance of guidance to crews emphasizing the importance of appropriate use of very high frequency radio for safe navigation.

•  Ensuring design principles in ASTM International Standard F1166 are incorporated when modernizing complex systems such as steering and control systems within the Integrated Bridge and Navigation System.

•  Revision of written instructions for bridge watchstanders on destroyers equipped with the Integrated Bridge and Navigation System to include procedures for shifting steering and thrust control between all bridge stations.

•  Revision of Integrated Bridge and Navigation system technical manuals to include a description of and procedures for ganging and unganging throttles.

•  Revision of training standards for helmsman, lee helmsman and boatswain’s mate of the watch for destroyers equipped with the Integrated Bridge and Navigation System to require demonstrated proficiency in all system functions including transfer of steering and thrust control between all bridge control stations.

•  Instituting Seafarers’ Training, Certification and Watchkeeping Code rest standards for all crewmembers aboard naval vessels.

The U.S. Navy's own review, following the John S McCain and USS Fitzgerald collisions, found significant systemic gaps, including:

•  Inconsistent headquarters management of the command and control and readiness of assigned forces.

•  Gaps in the way seamanship and navigation skills are provided and assessed for individuals and teams on surface ships – notably in the SWOS Basic Division Officer Course, which is only long enough to cover half the content required for qualification. The balance of the material is the "responsibility of the ship's training programs" and is completed on the job. 

•  Inconsistencies in the configuration and oversight of bridge navigation systems – including serious issues with the interface on mission-critical controls, like the throttle and helm control system on the USS McCain.

•  Gaps in the qualification and proficiency of the surface force in seamanship and navigation.

•  Gaps in the shiphandling trainers and associated shore-based infrastructure to support training for safe navigation at sea.

•  A reflexive “can-do” attitude, which ultimately led to an unrecognized accumulation of risk and a reduction in readiness.

The NTSB report is available here. Portions of Marine Accident Report 19/01 have been designated as Controlled Unclassified Information by the U.S. Navy and those portions have been redacted.