Accession Number:



Alternative Submarine Watch Systems: Recommendation for a New CF Submarine Watch Schedule (Systemes Differents d'Horaire de Garde a Bord des Sous-Marins: Nouvel Horaire Recommande Pour les Sous-Marins des FC)

Descriptive Note:

Technical rept.

Corporate Author:


Report Date:


Pagination or Media Count:



The summer 2007 at-sea trial to evaluate the Canadian Forces CF submarine watch schedule revealed dangerously low levels of modeled cognitive effectiveness among the crew. In response, Defence Research and Development DRDC Toronto hosted an International Submarine Watch Schedule Symposium CF, USN United States Navy, RN Royal Navy, RAN Royal Australian Navy, and RNLN Royal NetherLands Navy to review International experience with National watch schedule challenges and to model alternative watch schedules that would be more sparing of crew performance. Three alternative watch schedule systems were modeled 1-in-3 straight eights, 1-in-3 straight fours, and 1-in-2 8on-4off-4on- 8off. These three alternative watch systems were compared to the current 1-in-2 6on-6off-6on- 6off CF submarine watch schedule. The mean modeled cognitive effectiveness for all watches within each system were 96, 96, 89 and 66 for the 1-in-3 straight eights, 1-in-3 straight fours, 1-in-2 8-4-4-8 and the current CF 1-in-2 6-6-6-6, respectively. While it is evident that the best of these alternative watch schedules are the 1-in-3 straight eights and 1-in-3 straight fours both resulting in 96 mean cognitive effectiveness, it is also evident that only larger submarines with larger crews nuclear-powered USN and RN ballistic missile submarines and nuclear-powered USN attack submarines can employ such a watch system. Smaller diesel-powered attack submarines have small crews which makes it impossible for such boats to operate either the 1-in-3 straight eights or the 1-in-3 straight fours. Essentially, small diesel-powered submarines must employ a 1-in-2 watch system i.e., work 12 hours each day.

Subject Categories:

  • Personnel Management and Labor Relations
  • Military Operations, Strategy and Tactics

Distribution Statement: