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An Assessment of Some Watch Schedule Variants Used in Cdn Patrol Frigates: OP Nanook 2011

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Technical rept.

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Previous research conducted by DRDC-Toronto to evaluate watch schedule variants used on Royal Canadian Navy RCN submarines indicated very significant and deleterious effects of the watch system on modeled cognitive effectiveness of RCN submariners. Subsequently, DRDC-Toronto hosted an International Submarine Watch Schedule Symposium which led to a new RCN submarine watch schedule that improved modeled performance by about 30. The RCN surface fleet is aware of this work and supported a request to conduct an evaluation of the surface fleet watch schedule. We evaluated the watch schedules used aboard HMCS St Johns, a Halifax-class frigate, at the end of Op Nanook 2011 over the 8 days that the ship transitioned from the high Arctic to Halifax. The ages of the 45 sailors who participated in this at-sea trial ranged from 21 to 48 years. Ten of these sailors were non-watch-standers, 14 sailors were from the 1-in-2 Port Front watch, 14 sailors were from the 1-in-2 Starboard Back watch, three sailors were from the 1-in-3 Engineering watch, and four sailors were from the 1-in-4 Engineering watch. All subjects wore wrist activity monitors actigraphs to measure their daily sleep patterns quantitatively. The actigraphically measured sleep and daily work hours were the two data sets that were input into the FAST Fatigue Avoidance Scheduling Tool software to generate modeled cognitive effectiveness for each subject. All subjects maintained a daily activity, sleep, and mood log. Modeled cognitive effectiveness showed worrisome levels of performance equivalent to intoxicated levels of blood alcohol BAC 0.05 and 0.08 and well beyond those levels for all watch system variants. The authors conclude that the current surface fleet watch schedule is sub-optimal in that it results in worrisome levels of cognitive effectiveness in many of our sailors. An alternative watch schedule that is more sparing of submariner cognitive effectiveness should be developed and implemented.

Subject Categories:

  • Psychology
  • Personnel Management and Labor Relations
  • Stress Physiology
  • Marine Engineering
  • Military Forces and Organizations

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