The cause of the collision of an American destroyer was a tangled UI.

The management console destroyer USS John S. McCain (illustration from the report of the US Navy)



On November 1, 2017, a special commission of the US Navy published a multi-page report on the collisions of destroyers with guided missiles USS Fitzgerald (DDG-62) and USS John S. McCain (DDG-56) this summer.



The USS John S. McCain incident happened on August 21. He became the fourth collision involving the US Navy this year, and resulted in the death of ten sailors. The investigation revealed that both clashes that occurred this summer could have been avoided. And in the case of USS John S. McCain, experts recognized that "the user interface definitely played a role in the central navigation and control system on the bridge." Although the main part of the blame lies on the inadequate training of the crew, but the interface is objectively recognized too complicated and confusing.



As stated in the report, at 5:19 local time, the destroyer captain, Commander Alfredo Sanchez, “noticed that the helmsman was having difficulty keeping the ship's course while simultaneously driving the throttles to change speed”.



Seeing that the helmsman simultaneously performs two tasks, the commander ordered that the work be divided into two observation posts. The second is located right next to the steering position, which stands in front of the central navigation and control system. The disposition is shown in the diagram below, here the second post is designated as Lee Helm (“left hand drive”).





The scheme of the bridge destroyer USS John S. McCain (illustration from the report of the US Navy)



Commander Sanchez ordered that the steering be carried out from the previous post, and throttling from the other. This is not because the steering wheel is only at the central post, but you can also throttle at the second. No, everything is computerized on the destroyer: you can track and change speed with trackballs, while the result of the manipulations is shown on the computer screens of each of the posts. That is, you can control the ship simultaneously from two posts.



And here the incident happened. Instead of transferring only throttling to the next post, the helmsman accidentally transferred the entire control of the destroyer there . When this happened, the ship's steering wheel automatically moved to its default position (i.e., central, middle). Not knowing this, the helmsman slightly turned the steering wheel to the right to keep the course during the Singapore Strait. But in reality, the action of the helmsman led to the fact that the ship left the course. No one could understand why this happened.





While the USS John S. McCain team was trying to find out why the ship had lost its course, the destroyer turned and crashed into Alnic MC (illustration from the report of the US Navy)



The report states that the transfer of steering to the post of Lee Helm went unnoticed by the crew, and the unexpected change in the course of the destroyer caused general confusion. All decided that the ship had lost steering. There was confusion, during which Commander Sanchez and especially the crew lost control of what was happening and began to make stupid mistakes.



Since everyone thought that the steering was lost, Commander Sanchez ordered the engines to be slowed down, but the left steering (from the post of Lee Helm, where the engines went over) covered not all but only one (left) throttle, since the control of the left and right throttle by that time it was not synchronized (ganged). The destroyer entered the course of a collision with a transport ship for the transport of chemical products Alnic MC under the flag of Liberia.



Three minutes later, the steering was restored from the aft steering column, but it was already late and the ships collided at about 5:24. None of them gave a standard danger signal before a collision, and Alnic MC did not even try to change course.





The destroyer USS Fitzgerald (DDG-62) after a collision with a merchant ship on August 21, 2017



The consequences of the collision are well known from the press: ten sailors died, five were injured. Captain Alfredo Sanchez, Commander, and Commander Jesse Sanchez, Senior Officer, were relieved of their duties on October 11 by a decision of Vice Admiral Phil Sawyer, Commander of the Seventh Fleet. Both were removed due to loss of confidence.



Such a strange confluence of circumstances - the collision of destroyers of the same class with civilian vessels and the death of sailors in both cases - caused a lot of idle talk. At first, there were versions of cyber attacks on a computer destroyer control system or on GPS spoofing by intruders





But the investigation revealed that there was no cyber attack. It’s all a matter of poor sailor training, insufficient training and an intricate interface of the central navigation and control system on the bridge.