Originally Posted by tbctx
I suspect 6 6 5 4 3 is the number of hours for a watch for two people rotating back and forth.
0600-1200, 1200-1800, 1800-2300, 2300-0300, 0300-0600.
Sorry - that was rather cryptic. I use it with large crews as well. There is a 48 hour cycle.
This summer we had 6 (later 5 - other story) crew and had 3/2 on each watch. With no autopilot, it was necessary to change the helm at least every hour..
The six hours during the day is quite nice, it also allows each crew member to get a great sleep. I usually sleep when I am off in the 6 hours in morning. In the 6 hour afternoon, I got cleaned up, read, did some instruction with the on duty watch (I was instructing an offshore course).
The worst watch is 0300 - 0600 which is why it is so short.