Battle Bridge

The Battle bridge is an auxiliary control center located on some types of Starfleet vessels, such as the Galaxy- and Prometheus class starships. Since vessels of these and similar classes are designed to separate as a routine measure, duplicates of key systems are needed throughout multiple hulls, including command areas. Located on Deck 8 (Galaxy) and Deck 5 (Prometheus) of the secondary hull, this bridge duplicates most of the stations and functions of the main bridge, such as a viewscreen, the captain's chair, conn, ops, and tactical, but places emphasis on piloting, support, and defensive operations. The main bridge and battle bridge are connected by a dedicated emergency turbolift which can be accessed from other decks as well. The battle bridge can also be entered by standard turbolift or through a corridor. A small captain's ready room is located on the port side of the bridge, although it is much smaller than the one off the main bridge and lacks a window. Although the battle bridge could potentially be used to control the entire ship in the event of damage to the main bridge, command is usually rerouted to Main Engineering.

Note: The Prometheus class also incorporates an "auxiliary bridge" on Deck 10, as this ship separates into three distinct vessels (see multi-vector assault mode).

To keep in tune with changing technologies, the battle bridge is modular like the main bridge. The Enterprise-D had at least two different battle bridges installed during its lifetime. The version launched with the ship had the captain's chair in the center, with conn and ops to the front of the captain and tactical behind. Two duty stations were located at the back of the bridge, on the port and starboard rear walls. The tactical and rear stations were separated by turbolifts; the standard turbolift on the port side, and the emergency turbolift on the starboard. By the time of the second Borg incursion in 2367, the battle bridge was slightly modified. The tactical position behind the captain had been moved to the port station, replaced by expanded information displays. The turbolift alcoves at the back of the bridge were also gone, possibly moved elsewhere.

The term "battle bridge" came into use in the 2250s as a secondary control center being implemented in a limited number of larger ships, such as the Excelsior class (the USS Enterprise-B had one on Deck 19) and later the Ambassador class. At the time, both Romulan and Klingon captains made it a point at the onset of any engagement to target an enemy ship's main bridge. But as shielding technology advanced, the need for another bridge faded and those ships equipped with them had them converted to command-and-control centers for multi-ship operations or removed altogether. (Star Trek Generations)

The outbreak of the Dominion War, however, once again proved the need for a second bridge. These are typically referred to simply as Auxiliary Control Centers.