The U.S. Navy currently maintains a force of approximately 550,000 full-time employees, about 35 percent of whom are civilians. At any given time, 130-plus of the Navy’s 283 ships are under way, about 45 percent of the total ship inventory. In 2004 the Chief of Naval Operations (CNO), then Admiral Vern Clark, directed the Navy to maximize capabilities, minimize payroll, improve productivity, and eliminate unnecessary billets. One way to meet those goals is to remove sailors from billets that have little to do with war fighting and replace them with civilians. At sea, for instance, sailors cut hair, serve meals, maintain the engineering plant, chip paint—all tasks that civilians are equally capable of performing, and in fact do perform at commands ashore. Placing civilians on warships to perform those functions is a logical extension of the CNO’s guidance and would free sailors for combat-related activities.There's a lot more, go read.
Accordingly, one of the Navy’s answers to the CNO’s challenge is an experimental program to place federal civil-service mariners on board warships. These mariners perform tasks naval personnel have traditionally performed on board warships but that civilians have performed on board naval auxiliary vessels for decades and on board merchant vessels for centuries—navigation, engineering, and deck seamanship. For example, in early 2005 USS Mount Whitney (LCC/JCC 20) deployed to the European theater as the new U.S. Sixth Fleet and North Atlantic Treaty Organization (NATO) command ship. One of the most sophisticated command, control, communications, computer, and intelligence (C4I) ships ever commissioned, Mount Whitney today is manned by a composite crew of 157 U.S. Navy sailors and 143 civilian mariners employed by the Military Sealift Command. These three hundred personnel represent a reduction of 276 from the previous all-active-duty Navy crew. “By supplementing the crew with civilian mariners,” the Sixth Fleet Public Affairs Office reports, “the Navy is operating the command ship at a reduced cost and employing captured uniformed personnel billets on forward combatant vessels.”
...Of particular interest for this discussion is the role of the MPF-F cargo ship. The MPF-F is designed as the replacement for today’s logistics-force cargo ships and would act as a floating logistics center. One report notes that it would be “nearly as large as an aircraft carrier” and would “accommodate heavy-lift helicopters and perhaps cargo planes as large as the Air Force’s C-130. It would be able to move supplies and equipment to those aircraft and other ships while at sea.”8 Another report, however, depicts a role directly involved in combat operations. It refers to the MPF-F as a replacement for the big-deck Tarawa-class amphibious assault ships, describing it as a “fighting logistics ship with a flight deck big enough to send hundreds of Marines ashore in rotorcraft and launch Joint Strike Fighters.”9
Civilians who assist in operating and maintaining a warship engaged in international armed conflict might be viewed as having lost their protected status.
If the MPF-F is manned as prepositioning ships are today, its crew will consist entirely of civilian mariners. There is no legal prohibition against manning naval auxiliaries, such as oilers, ammunition ships, supply ships, and prepositioning ships, with civilians. In fact, these seamen have a recognized status under the Geneva Conventions as “civilians accompanying the force” and are entitled to prisoner-of-war status if captured.10 Issues arise, however, if the MPF-F is indeed to become part of the “assault echelon”—if Marines or soldiers actually launch from the ship into combat operations ashore. Similar issues will arise if USS Mount Whitney, with its hybrid crew, is employed as a C4I platform in an armed conflict.(footnotes omitted)
(Hat tip: NOSI)