The composition of the crew on each ship varies according to its class, and its function. The normal bridge personnel complement includes the captain, first officer, navigator, helmsman and an electronic-emissions specialist. The rest of the crew is usually composed of engineers and a staff of technicians and bosuns. Depending on the function of the vessel, EVA specialists, stewards and any number of possible positions are necessary to operate a vessel. Vessels with smaller crew complements will often combine or overlap positions.

CAPTAIN & FIRST OFFICER
The captain of a vessel is the person ultimately responsible for everything that happens onboard the ship placed under their care. The conduct of the vessel through space, compliance with international and local regulations, crew safety and actions and the state of the vessel are just some of the many things a captain is occupied with while the vessel is in operation. Since it is not uncommon for the vessel’s owner to also be the captain, there are numerous other tasks that are the concern of the captain, such as refits, fuel, cargo rates and all the aspects of running a business. A common career background for a captain is either as a senior bridge crew member or engineering department head, with the former being the most common.

The first officer is responsible for the day-to-day operations of the vessel. The heads of each department report to the first officer, who reports any pertinent information to the captain. The first officer is responsible for finding the right people to fill the various positions aboard the vessel, usually in consultation with department heads. Crew quarter assignments and duty schedules are made by the first officer. When the captain is not present on the bridge, the first officer (or the next most senior bridge crew member) is in command. When docked at a port facility, the first officer must be on the ship if the captain is not on the ship.

NAVIGATOR & HELMSMAN
The navigator and helmsman are not always the same person, but the two positions are very similar and often interchangeable on the smaller ships. Both positions require a thorough knowledge of basic physics and space navigation methods and procedures. In addition to basic course plotting duties, the navigator is responsible for ensuring that flight plans are filed before departure, that said flight plan is respected and that any deviations are reported quickly and efficiently to authorities; the navigator also alters the flight plan as necessary to account for changes in mission or destination. The helmsman is responsible for ensuring that the flight plan is followed, that all necessary maneuvers are carried out in the proper manner, and that all flight systems are operating properly. He carries out the captain’s or first officer’s flight directives and handles crucial maneuvers such as docking.

ELECTROMAGNETIC EMISSIONS SPECIALIST
The electromagnetic emissions (EME) specialist is the person responsible for operating and maintaining the eyes and ears of a vessel – the sensor and communication systems. On some larger civilian vessels, and on most military vessels, this position is actually divided into two positions that take care of sensors and communications, respectively. The EME specialist is stationed on the bridge of the vessel, ensuring that the space within reach of the vessel’s sensors is safe to traverse. The EME specialist also ensures the flow of information between the vessel and the rest of the Solar System. All incoming and outgoing communications traffic must be logged, and possibly checked, to ensure proper use of this vital resource. On smaller vessels where personnel are limited, the EME specialist is also responsible for the maintenance and repair of the vessel’s sensor and communication equipment.

EXTRA-VEHICULAR ACTIVITY SPECIALIST & BOSUN
Extra-vehicular activities (EVA) specialists commonly undertake inspections of, and repairs on, a vessel’s exterior, or transfer equipment and supplies between vessels. The EVA specialist is trained not only in a specialist field (like a technician), but also to perform in a zerogravity environment effectively and efficiently. This involves a thorough knowledge of spacesuit use, M-pod operations, airlock operation, numerous safety procedures and the intricacies of moving in zero-gravity.

A bosun is responsible for the maintenance of the vessel’s hull and structural framework. Often having cross-training in other technical areas, much of the bosun’s time is spent outside the ship inspecting the hull and frame, and patching cracks and abrasions caused by debris and stress. A common part of the bosun’s job is also the maintenance of the vessel’s point defense systems. Since a lot of the work a bosun performs is exterior, they are experts at WAS. This means there is a lot of double duty; when not performing their own set of tasks, bosuns and EVA specialists often assist each other.

ENGINEER & TECHNICIAN
An engineer is trained to have a detailed understanding of the vessel’s systems as a whole. The majority of an engineer’s time is spent monitoring the vessel’s plasma chambers and other vital systems. If an engineer is not directly involved with vessel operations, maintenance, repairs, or modifications, the engineer is supervising someone who is involved in such activities.

Technicians are the “mechanics” of a vessel’s many systems. Whether the technician is trained to maintain mechanical devices, electrical systems, computer systems, or auxiliary craft, a technician’s shift is filled with numerous tasks related to their area of expertise. Given the level of integration between systems, most technicians have some multi-disciplinary training to efficiently carry out their tasks.

SECURITY SPECIALIST & STEWARD
One of the unpleasant facts of living and working in the close confines of a vessel is that small problems can become big problems. The security specialist has numerous duties that involve ensuring the safety of crew, passengers and cargo. More commonly found on vessels with large crews or carrying passengers, the security specialist’s primary duty is to enforce discipline. If there is a physical conflict, they are responsible for separating and confining the combatants until the captain takes disciplinary action. The security specialist’s training also means he is responsible for coordinating and conducting any defense against someone attempting to board the vessel in open space.

Since the captain or owner of the ship is also responsible for the conduct of their crew, any crew member caught smuggling contraband is not the only one affected by the law should they be caught. The security specialist, therefore, acts on behalf of the rest of the crew to ensure compliance with the laws of any port nation. A law enforcement officer is not always available to investigate a crime that takes place in space, so in such cases, the security specialist will begin the investigation until it is handed over to another agency.

While more common aboard passenger vessels, stewards are also found on other commercial vessels. Small vessels will have crew rotate food preparation duties, or the crew will stock the galley (a small kitchen and mess area) with pre-packaged prepared foods. Larger vessels, with their correspondingly larger crews, will have a steward to prepare meals and coordinate leisure activities for the crew.