Star Trek: The Next Generation's iconic starship, the USS Enterprise NCC 1701-D, could split into two parts, with the saucer section detaching from the secondary hull and warp nacelles. It rarely did so, however, with only three such maneuvers during all of TNG's 176-episode run and a fourth and final time in Star Trek Generations. The Enterprise-D's bridge officers raised saucer separation as an option in several more episodes, but the tactic only played out onscreen those four times. Captain Jean-Luc Picard (Patrick Stewart) typically dismissed the idea quickly and stressed that it would only be used as a last resort.
Picard's version of the Enterprise was the only hero ship to separate its saucer onscreen, although Star Trek technical manuals indicated Captain James T. Kirk's (William Shatner) Constitution Class Enterprise had saucer separation capabilities. During separation, civilians could flee to safety in Enterprise's saucer while the ship’s Starfleet crew stayed behind in the stardrive section and battled their attackers. It was also for evacuating civilians and crew in the event of a warp core breach. As a practical matter, the costs of 1980s visual effects and the second bridge set kept TNG from breaking the ship in two more often. Here's a rundown of each time the Galaxy Class Enterprise-D separated its saucer section.
