HRO 9g What's a Warship Bridge Like?-External Focus

Because I believe neither accident report (Navy, ref (a); NTSB, ref (b)) provides adequate context, this post helps non-Navy Surface Warfare Officers understand the high mental workload on the Bridge before the collision. It emphasizes the attention an OOD must devote to the situational features external to the ship.

I abbreviated the reference details to conserve space. Refer to the original post for the complete information.

References

(a) Navy Report of the Collision https://www.doncio.navy.mil/FileHandler.ashx?id=12011.

(b) National Transportation Safety Board (NTSB) Report of the Collision https://www.ntsb.gov/investigations/accidentreports/reports/mar1901.pdf

(c) International Rules of the Road https://en.wikisource.org/wiki/International_Regulations_for_Preventing_Collisions_at_Sea.

(d) U.S. Navy Regulations, Chapter 8, https://www.secnav.navy.mil/doni/US%20Navy%20Regulations/Chapter%208%20-%20The%20Commanding%20Officer.pdf

(e) Standard Organization and Regulations of the U.S. Navy, OPNAVINST 3120.32D CH-1, dtd 15 May 2017, https://www.secnav.navy.mil/doni/Directives/03000%20Naval%20Operations%20and%20Readiness/03-100%20Naval%20Operations%20Support/3120.32D%20W%20CH-1.pdf

Summary of the Incident

The USS JOHN S MCCAIN (JSM) was overtaking the ALNIC MC in the westbound lane of the Singapore Strait Traffic Separation Scheme when bridge watchstanders thought they lost steering control (but they didn’t). While the crew attempted to regain control of forces they unwittingly released, the JSM unintentionally turned to port into the path of the ALNIC MC. The resulting collision killed 10 Sailors, injured 48 more, and caused over $100 million in damage.

The event descriptions provided by both reports prior to the collision were not sufficient to understand the situation on the Bridge just prior to the perceived loss of steering on the JSM. The demanding task environment faced by an Officer of the Deck (OOD) and Conning Officer on the Bridge of a Navy warship at night has few equals. The Commanding Officer’s (CO) order to station a new watchstander that required changing the configuration of steering control interrupted an already challenging situation for these two officers to manage safely.

Safely guiding a ship through an area where there are many other ships is one of the most complex tasks humans face. The overall responsibility of the OOD of a U.S. Navy ship to the CO is for “safe navigation and tak[ing] action to avoid the danger of grounding or collision” (ref (e), p.4-17). To keep the length of this post tractable, I will split the responsibilities of the OOD into the external environment (this post) and the internal environment of his own ship (next post).

To effectively monitor the external environment of the ship, the OOD must:

• know the location of navigational aids and hazards,

• receive and analyze course and speed recommendations from the Navigation team on the Bridge and Combat Information Center (they diverge sometimes), and

• maintain awareness of all ships nearby (distances, courses, speeds, risk of collision).

To avoid the danger of grounding, the OOD must be constantly aware of own ship position, the location of navigational hazards, the location and features of navigational aids warning of these hazards, the course and speed recommended by the Navigation Team to reach the ship’s destination, and when that course and speed is about to change so he doesn’t collide with another ship while maneuvering. There are many high tech displays available to the OOD that simplify this task, but every second spent studying such a display (or the actual chart on the other side of the Bridge in the old days) is time not devoted to watching and interpreting the movements of other shipping.

To avoid collision, the OOD must maintain multiple dimensions of awareness of ships nearby. For each ship, he or she must assess its risk of collision with own ship, if it is maneuvering to avoid hazards and other shipping, if it is entering or leaving the Traffic Separation Scheme (TSS), its responsibilities with respect to Rules of the Road (ref (c)), whether it appears to be complying with those responsibilities, what needs to be communicated to the Commanding Officer about the ship in accordance with Standing Orders, and if he or she should communicate with personnel on the other ship’s bridge to clarify intentions.

The definition of “nearby” is situational, depending on the amount of shipping traffic, own ship’s course and speed, and restrictions on the ship’s ability to maneuver. Sometimes nearby might be a ship 5 miles away. Other times it might be ships within 1000 yards because there are too many within 5 miles to maintain focus on each one. Depending on shipping density, the OOD may have to pay close attention to one ship or more than twenty. I have never seen this addressed in Commanding Officer’s Standing Orders.

To make things more interesting, all of these things are changing constantly. A ship that presented no risk five minutes ago could suddenly change course and be a collision risk. There is no Air Traffic Controller to manage the traffic. Each ship in a Traffic Separation Scheme is free to maneuver as they need to. This means the OOD must constantly update his understanding of the ship’s environment and the risk of collision it presents.

Effect of Darkness

The cognitive demand placed on the OOD and Conning Officer by the environment increases significantly at night. Information collected by radar about other ships must always be confirmed visually. At night, the only way to do this is by analyzing navigational lights and their changes based on the relative motion between the external ship and own ship. As the lights of ships on the same bearing but at different distances from own ship appear to merge and diverge, it is very difficult to keep a mental representation of which ship is which and the danger each presents to own ship.

When I was on my first ship, I remember hearing a Department Head tell other officers of the difficulty he (OOD) and his Conning Officer had maintaining the correct position in a complicated, moving array of Navy ships maneuvering in formation at night. As an aid, he and the Conning Officer created a diagram of the formation specifying each ship’s area to supplement their radar picture. They provided this diagram to the watch team that relieved them and used it to explain their position in the formation (the “tactical picture” in Navy terms). When the second watch team observed sunrise and could visually identify each of the ships in the formation, they discovered that the diagram was TOTALLY WRONG. When he learned later that his diagram was incorrect, the Department Head’s response was, “Well, it worked for us” (much laughter ensued). This could be an illustration of Karl Weick’s observation that when you’re lost in a snowstorm in the Alps, even a map of the Pyrenees can can help you get back to base (Weick, 1995).

* Weick, Karl E. (1995). Sensemaking in organizations (Foundations for organizational science series). Sage Publications.

In my next post, I will review the awareness the OOD must maintain of the conditions aboard his or her own ship.