A watch system, watch schedule, or watch bill is a method of assigning regular periods of work duty aboard ships and some other areas of employment. A watch system allows the ship's crew to effectively operate the ship 24 hours a day for the duration of long voyages or operations.
Many watch systems incorporate the concept of dogging, whereby one watch is split into two shorter watches so that there is an odd number each day. Doing so allows crew members to have a different watch schedule each day. Often, the dog watches are set at dinner time to allow the entire crew to be fed in short order.
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Traditional system
In the traditional Royal Navy watch system (a system used by most other Commonwealth navies), 'watch' refers to a period of time and to a grouping of personnel. Those members of the crew whose work must be done at all times of the day - known as 'watch-keepers' - are assigned to one of two watches: the Starboard or the Port watch. These can be further divided into two parts, e.g. First Port, Second Starboard. These two watches - or more usually the four parts of watches - alternate in working the following watches:
- First watch: 2000 to 0000
- Middle watch: 0000 to 0400
- Morning watch: 0400 to 0800
- Forenoon watch: 0800 to 1200
- Afternoon watch: 1200 to 1600
- First dog watch: 1600 to 1800
- Last dog watch: 1800 to 2000
The Royal Navy traditional submarine three watch system is 2 on 4 off during the day (8 a.m. to 8 p.m.) and 3 on 6 off during the night (8 p.m. to 8 a.m.).
Dog Watch Systems Video
Traditional system with three sections
The same arrangement of watch times can also be used with a crew divided into three sections. This gives each sailor more time off-duty, sometimes allowing sleeping periods of over seven hours. Names for the three watches--instead of Port and Starboard--vary from ship to ship. Naming schemes such as "Foremast", "Mainmast" and "Mizzen" and "Red", "White" and "Blue" are common.
Five and dime
The so-called "five-and-dime" arrangement splits the day into five-hour watches, with the exception of a four-hour watch from 22:00 to 02:00.
Six Hour Shift
The "Six-Hour-Shift" splits the day in four 6-hour watches, permitting a three section crew to maximize rest time in a 3-day working cycle. Also, this watch systems takes into better account the meal times (of a 4 meal-a-day system), so that the ingoing team will be fed first, then stand watch, while the outgoing team will be relieved of watch, and then proceed to the messdeck.
US submarine system with three sections
Aboard United States submarines, where the working day is 18 hours instead of 24, the crew is normally divided into three sections, with each section standing 6 hours of watch followed by 12 hours off-watch. The 12 hours off-watch are further divided into the first 6 hours being used for maintenance, cleaning, and entertainment; while the second 6 hours are usually for sleeping.
Note that this arrangement results in one of the sections having two watches in one (24-hour) day, and there are no dog watches. Also, watch reliefs occur no later than the bottom of the hour (2330, 0530, 1130, 1730). This is because the first 30 minutes of the hour are used for the oncoming section to eat, and the second 30 minutes of the hour are used for the off-going section to eat.
One-in-two watch system
Some warships now use the one-in-two system, also known as 7s and 5s, for the duration of the watches. This gives the sailors a longer sleeping period than the traditional two-watch system, while still maintaining the ability for the ship to function. Meals are generally scheduled around the watch turnovers at 0700, 1200, and 1700; sometimes a light midnight meal is provided for the 0000 turnover.
Swedish system
Various alternative watch schedules have been devised, which are typically referred to as Swedish watches. Although there is no standard for what constitutes a Swedish watch, the variations all feature some element of extended watches to accommodate longer time off. Like the traditional watch system, they begin at 2000 hours. Some popular variations have durations of 6, 6, 4, 4, 4 and 5, 5, 5, 5, 4.
Merchant ships
On merchant ships, watchstanders typically stand watch for three periods of four consecutive hours. This system has a couple of advantages: it is easy to remember and it is consistent. For example, a member of watch team 1 will only have to remember that he is on the "4-8" watch, and knows that he goes on watch at 4 a.m. and 4 p.m. This scheme also allows inexperienced watchstanders to stand watch from 8-12 a.m. and 8-12 p.m., when senior watchstanders are likely to be awake and ready to assist in case of trouble.
By custom, in a ship with five deck officers the junior third mate takes the 8 to 12 watch, the senior third mate the 12 to 4 watch, and the second mate the 4 to 8 watch. This enables the second officer, who is the ship's navigator, to take morning and evening star sights. In ships with only four deck officers, the third officer will stand the 8 to 12, the second officer the 12 to 4, and the Chief Mate (equivalent to the Executive Officer in a navy ship) the 4 to 8 watch. The reason for this is to enable the Chief Mate to assign work to the deck gang before the ship's day begins, and to inspect it before going on watch at 1600 hours.
Source of the article : Wikipedia
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