The purpose of a watch keeping system is to keep those actively sailing the boat alert, whilst allowing those not actively engaged in sailing the vessel to rest. In this way the boat is sailed more efficiently on longer passages.
During daylight hour passages, of say 12 hours, a formal watch keeping system may not be required provided that at least one person accepts responsibility for keeping a lookout.
But as the duration of passages increases, night sailing becomes involved, and the seasons have shifted into autumn and winter so the benefits of a formal watch keeping system grow.
Next a selection of watch keeping systems are discussed.
Watches of 4 hour duration are not usually too arduous during summer weather. But in the depths of winter it may be necessary to shorten the period of each watch and increase the number of changeovers.
The system below is for a two man system, where each watch is four hours duration.
This system the author has used on successfully on two-handed trips. Usually there is more than enough time for each person to get enough sleep, and so quite often a well rested crew member will offer the other the chance to have an extra period of watch - if conditions have meant that the other has lost the opportunity for some sleep.
It's also a system that I have used successfully with three people onboard, where both crew members have been enthusiastic but inexperienced.
|<------------------ Skipper floats, present all sail changes, navigates and does all cooking ---------------->|
Such a system I have not seen described in any book but it has the following merits.
A system which often appears in books is shown below, where each person spends 4 hours on watch, followed by 4 hrs on standby during which they might get called for sail changes, followed by 4 hours on watch, then 4hrs undisturbed rest off watch. This system can provide up to eight hours sleep for each person. It is quite suited to longer passages and open water - where if the skipper is the navigator as well, the demand son his time in the latter role is reduced (compared to say a passage parallel and close to a coastline).
|B On Standby||C On Stand By||A On Stand By||B On Stand By||C On Stand By||A On Stand By|
|C Undisturbed rest||A Undisturbed rest||B Undisturbed rest||C Undisturbed rest||A Undisturbed rest||B Undisturbed rest|
A variation on this theme is to introduce a dog-watch, whereby each persons watch hours change each day. For example:
|B Stand By||C Stand By||A Stand By||B Stand By||C Stand By||A Stand By|
|C Rest||A Rest||B Rest||C Rest||A Rest||B Rest|
|C Stand By||A Stand By||B Stand By||C Stand By||A Stand By||B Stand By|
|A Rest||B Rest||C Rest||A Rest||B Rest||C Rest|
|A Stand By||B Stand By||C Stand By||A Stand By||B Stand By||C Stand By|
|B Rest||C Rest||A Rest||B Rest||C Rest||A Rest|
Each of the above systems can be adapted for 4 or more persons. For example:
Always brief the crew on the watch keeping system being adopted. Remind each person that whilst on watch, they are the most important person on board, as the safety of all onboard rests on their shoulders. Hopefully this reminder encourages the individual to keep an eye out for other vessels, and sea borne debris.
The skipper must remind the watch keeper that he can be called if there is anything the watch is unsure of (e.g. predicting the movements of another vessel, or spotting an unexpected navigational mark or light).
The watch keeper has the right to call all hands if the situation demands, and it is the responsibility of all below to respond by turning up on deck immediately.
Each skipper must review the factors of the passage to be undertaken, the number and experience of the crew members, the level of navigational demands, and the weather expected and devise the most appropriate watch system. The system chosen may be one of those described above or some variation.
I myself have used the two person 4 on 4 off system, but changed it mid way through a passage to a 2 hrs on 2off system when conditions became particularly demanding - before returning to a 4 hrs on 4hrs off system, once strong winds and lumpy seas had moderated.
Flexibility is useful, and it helps to explain reasons both for an initial as well as any amended watch system to the crew.
Some other useful things for a skipper to consider:
Hopefully, the above discussion will be useful to skippers of crewed yachts.
For tactics used when single-handing ...
What does a watch keeper do ?