Life on board is divided into three six-hour shifts, with at least 12 crew members always on duty. Although the captain is formally part of the shift system he tends to stand outside it and will be on the bridge whenever he feels his presence is necessary. Typically, the captain and first officer will work the same shift, though in theory they each command a separate shift.
The three rosters-or ghom ngoy' in Klingon-operate in a strict hierarchy, with the most senior roster including all the command officers except the second officer, who typically heads up the second roster, and the third officer who moves between shifts. Whenever the ship is entering combat, the shift system is abandoned and all the senior crew members take their stations. The first roster takes command with all the other warriors on standby to replace anyone who falls in battle.
FIRST SHIFT [DUTY SHIFT]
Qu' poH wa'DIch
Officers and warriors on the duty shift are responsible for operating the ship. The bridge should always be staffed with at least four crew members, with two warriors assigned to the engineering section, one to the sensors, one to the weapons room and one to the medical bay, and one servant to the galley.
Klingon crews are rigorously drilled. Each duty shift involves a session of battle drills with the computers programmed to simulate the sensor inputs that would be generated in an actual battle. The drills take place under the supervision of the first or second officers and take two different forms. The first of these is used when the crew is on active battle duty. The computers are put into a simulation mode. Weapons are not fired and the ship continues on its pre-programmed course, but the consoles all behave as if the ship really were at combat and to the untrained eye it is impossible to distinguish the data they provide from the real thing.
This form of drill is necessary when the ship is cloaked or in times of war when it is important to conserve photon torpedoes. However the Klingons are keenly aware of the limitations of this kind of training and wherever possible they prefer to train with live weapons and active helm control. In these kinds of drills the computer still generates an artificial attacker, but the ship responds to the crew's commands, weapons are fired, the cloak is engaged and dropped and the ship actually performs the maneuvers ordered by the helmsman Many Klingon captains regard this kind of drill as insufficiently realistic and it is quite common for them to drop out of warp and spend time shooting asteroids as target practice.
The drills are supervised by the first or second officer, who note reaction times and administer discipline to crew members who do not meet the standard expected of them.
The officers assigned to the weapons room start each shift by recalibrating and testing the targeting sensors, and once every third shift stripping down and rebuilding the ship's supply of disruptor rifles.
SECOND SHIFT [LEISURE SHIFT)
Qu' poH cha'DIch
During the second shift the crew are at what loosely translates as leisure. In practice this means that they congregate in one of the two communal areas on the ship: the mess hall or the training hall. Off-duty crew members will invariably head to the mess hall rather than their extremely basic quarters and at least some crew members can always be found here. Meals are served at the beginning of each shift and it is common for the entire shift to eat together.
Even outside of 'formal' meal times the mess hall is furnished with a constant supply of gagh and dishes such as bregit lung. Other delicacies such as heart of targ or pipius claw are reserved for special occasions such as a significant victory.
On a successful ship, the captain will ensure there is a plentiful supply of bloodwine, but during active combat missions this is only consumed by the men on the second shift, ensuring the crew have time to sober up before they return to their duty stations.
During this shift crew members are also expected to practice hand-to-hand combat in the training hall, and to spend time studying tactics an the exact specifications of enemy ships. Senior members of the staff, such as the first officer, consider this shift to be a working one and use it to perform their admin duties.
THIRD SHIFT [SLEEP SHIFT)
Qu' poH wejDIch
The third shift is reserved for sleep and most warriors will spend it in their quarters.