Marine engineer

Ship (or marine) Engineering Officers or, simply, Ship Engineers are responsible for operating and maintaining the propulsion plants and support systems on board crew, passengers and cargo seafaring vessels or other watercraft. Alternative terms commonly employed to collectively refer to the profession are seagoing or seafaring engineer officers. Ship engineers / officers are usually educated and qualified as engineering technicians. In the United States they are usually trained via cadet ships sponsored by a variety of maritime organizations. Engineering Officer Cadets of most countries are sponsored during training by a shipping company, serving their time on board ships owned by that company. Many go on to work as Engineering Officers with their sponsoring company once training is complete.

Ship engineers are responsible for propulsion and other ship systems such as: electrical power generation plant; lighting; fuel oil; lubrication; water distillation and separation; air conditioning; refrigeration; and water systems on board the vessel. They require knowledge and hands-on experience with electric power, electronics, pneumatics, hydraulics, chemistry, steam generation, gas turbines and even nuclear technology on certain military and civilian vessels.

Ship Engineering Officers Ranks (typical for a British Merchant Vessel – US equivalents in italics):

United States Navy ships have a varying number of engineering officers, depending upon the size of the crew, occupying positions named for subsidiary responsibilities of the Engineering Officer. The two highest ranking subordinates are usually the Main Propulsion Assistant (MPA), responsible for operation and maintenance of propulsion machinery, and the Damage Control Assistant (DCA), responsible for prevention and control of damage. Anticipation of battle damage increases the significance of responsibilities of the latter position on warships. A DCA often stands routine deck or engineering watches, but spends his off-watch time overseeing maintenance of watertight integrity and firefighting equipment. A DCA's battle station normally includes responsibility for controlling the ship's stability, list and trim by flooding and dewatering undamaged compartments as necessary to prevent capsizing. Additional engineering officers may include an Electrical Officer, responsible for the ship's electrical generating and distribution system as described above, and an Auxiliaries (or A Division) Officer, responsible for pumps, ventilation blowers, refrigeration compressors, and windlass machinery as described above for the Fourth Engineer.

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Wikipedia