Physics:Watch system
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 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.[1] Doing so allows crew members to have a different watch schedule each day.[1] Often, the dog watches are set at dinner time to allow the entire crew to be fed in short order.[1]
Traditional system
| Day 1 | Day 2 | Day 3 | |
|---|---|---|---|
| 2000–0000 | Team 1 | Team 2 | Team 1 |
| 0000–0400 | Team 2 | Team 1 | Team 2 |
| 0400–0800 | Team 1 | Team 2 | Team 1 |
| 0800-1200 | Team 2 | Team 1 | Team 2 |
| 1200–1600 | Team 1 | Team 2 | Team 1 |
| 1600–1800 | Team 2 | Team 1 | Team 2 |
| 1800–2000 | Team 1 | Team 2 | Team 1 |
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[1]
- Middle watch: 0000 to 0400[1]
- Morning watch: 0400 to 0800[1]
- Forenoon watch: 0800 to 1200[1]
- Afternoon watch: 1200 to 1600[1]
- First dog watch: 1600 to 1800[1]
- Last dog watch: 1800 to 2000[1]
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.).
Traditional system with three sections
| Day 1 | Day 2 | Day 3 | |
|---|---|---|---|
| 2000–0000 | Team 1 | Team 2 | Team 3 |
| 0000–0400 | Team 2 | Team 3 | Team 1 |
| 0400–0800 | Team 3 | Team 1 | Team 2 |
| 0800–1200 | Team 1 | Team 2 | Team 3 |
| 1200–1600 | Team 2 | Team 3 | Team 1 |
| 1600–1800 | Team 3 | Team 1 | Team 2 |
| 1800–2000 | Team 1 | Team 2 | Team 3 |
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
| Day 1 | Day 2 | Day 3 | |
|---|---|---|---|
| 2200–0200 | Team 1 | Team 3 | Team 2 |
| 0200–0700 | Team 2 | Team 1 | Team 3 |
| 0700–1200 | Team 3 | Team 2 | Team 1 |
| 1200–1700 | Team 1 | Team 3 | Team 2 |
| 1700–2200 | Team 2 | Team 1 | Team 3 |
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
| Day 1 | Day 2 | Day 3 | |
|---|---|---|---|
| 0100–0700 | Team Blue | Team Gold | Team White |
| 0700–1300 | Team Gold | Team White | Team Blue |
| 1300–1900 | Team White | Team Blue | Team Gold |
| 1900–0100 | Team Blue | Team Gold | Team White |
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
| Day 1 | Day 2 | Day 3 | |
|---|---|---|---|
| 2330–0530 (Mid Watch) | Team 1 | Team 2 | Team 3 |
| 0530–1130 (Morning Watch) | Team 2 | Team 3 | Team 1 |
| 1130–1730 (Afternoon Watch) | Team 3 | Team 1 | Team 2 |
| 1730–2330 (Evening Watch) | Team 1 | Team 2 | Team 3 |
Aboard United States submarines, the crew is typically divided into three sections, with each section standing 8 hours of watch followed by 16 hours off-watch. This schedule has been a fairly recent change to submariner work and rest routines. For nearly 45 years prior to 2015, submariners were on 18-hour days with 6 hours of watch followed by 12 hours off watch. The 12 hours off-watch were further divided into the first 6 hours being used for maintenance, cleaning, and entertainment; while the second 6 hours were usually for sleeping.
Note that this arrangement resulted in one of the sections having two watches in one (24-hour) day, and there were no dog watches. Also, watch reliefs occurred no later than the bottom of the hour (2330, 0530, 1130, 1730). Typically, the first 30 minutes of the hour were used for the oncoming section to eat while the second 30 minutes of the hour were used for the off-going section to eat.
One-in-two watch system
| Day 1 | Day 2 | Day 3 | |
|---|---|---|---|
| 0000–0700 | Team 1 | Team 1 | Team 1 |
| 0700–1200 | Team 2 | Team 2 | Team 2 |
| 1200–1700 | Team 1 | Team 1 | Team 1 |
| 1700–0000 | Team 2 | Team 2 | Team 2 |
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
| Day 1 | Day 2 | Day 3 | |
|---|---|---|---|
| 0000–0600 | Team 1 | Team 1 | Team 1 |
| 0600–1000 | Team 2 | Team 2 | Team 2 |
| 1000–1200 | Team 1 | Team 1 | Team 1 |
| 1200–1400 | Team 3 | Team 3 | Team 3 |
| 1400–1800 | Team 2 | Team 2 | Team 2 |
| 1800–2400 | Team 3 | Team 3 | Team 3 |
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
| Day 1 | Day 2 | Day 3 | |
|---|---|---|---|
| 0400–0800 | Team 1 | Team 1 | Team 1 |
| 0800–1200 | Team 2 | Team 2 | Team 2 |
| 1200–1600 | Team 3 | Team 3 | Team 3 |
| 1600–2000 | Team 1 | Team 1 | Team 1 |
| 2000–0000 | Team 2 | Team 2 | Team 2 |
| 0000–0400 | Team 3 | Team 3 | Team 3 |
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.
See also
- Ship's bell: using a bell to indicate the time and the start of each watch.
- Watchstanding
- Work shift
Notes
References
- The Bluejackets' Manual (21st ed.). Annapolis, MD: United States Naval Institute. 1996 [1902]. ISBN 1-55750-050-9.
External links
- Research study on the 1-in-2 Watch System
- Description of Swedish Watch System
- Marine Technology Society; Oceanic Engineering Society (U.S.) (1984). Conference record. Institute of Electrical and Electronics Engineers. https://books.google.com/books?id=C_dVAAAAMAAJ. Retrieved 2 October 2011.
- Max Wood (31 August 2004). Sailing tall: around the world on the square-rigged Passat (1946–1948). Sheridan House, Inc.. pp. 26–. ISBN 978-1-57409-189-2. https://books.google.com/books?id=oR9FVn869jYC&pg=PA26. Retrieved 2 October 2011.
- George J. Collins; Kathy Alexander (April 2001). Chessie racing: the story of Maryland's entry in the 1997-1998 Whitbread Round the World Race. JHU Press. pp. 53–. ISBN 978-0-8018-6413-1. https://books.google.com/books?id=-Kc8pAxwP0gC&pg=PA53. Retrieved 2 October 2011.
- Yachting. CBS Magazines. April 1967. https://books.google.com/books?id=M6EjAQAAMAAJ. Retrieved 2 October 2011.
- International Maritime Economic History Association; Memorial University of Newfoundland. Maritime Studies Research Unit (2007). International journal of maritime history. Maritime Studies Research Unit. https://books.google.com/books?id=M9QJAQAAMAAJ. Retrieved 2 October 2011.
- Shay, Johnathan, M.D., Ph.D. (Summer 1998) "Ethical Standing for Commander Self-Care: The Need for Sleep" Parameters: 93–105 http://www.carlisle.army.mil/usawc/parameters/Articles/98summer/shay.htm. Retrieved 2011-10-02
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