The Aeon's launch bay
An NX class launch bay
A Defiant class launch bay.
A launch bay is a location from which vehicles, be they spaceborne or otherwise, are dispatched.
On a starship, a launch bay was the area from which shuttlecraft and other small craft may be launched, and where they are docked when not in use. The term was in common use in the 22nd century as by the 23rd century, the term shuttlebay was more common.
Sometime before late 1996, Henry Starling had constructed a launch bay within the uppermost floors of Chronowerx headquarters. This launch bay housed the Federation timeship Aeon, which Starling had appropriated in the year 1967. (VOY: "Future's End, Part I & II")
In the NX class of starship, the launch bay opened from the ventral hull and was capable of holding two shuttlepods. These shuttlepods both ingressed and egressed through two sliding doors, which were controlled from a control station on the upper gantry level; the launch bay was not capable of maintaining atmospheric pressure during launch, requiring repressurization after every launch. The launch bay is equipped with a telescoping arm to guide craft through these bay doors. The grappler is also housed on the ceiling of this bay. (ENT: "Cold Front", "Divergence")
Due to their compact size, the Defiant class also utilized a launch bay, instead of the larger shuttlebays used on other Starfleet ships of the late 24th century. The USS Defiant's launch bay was used by Type-18 shuttlepods and Type-10 shuttlecraft, such as the Chaffee. (DS9: "The Sound of Her Voice")
- Although the Defiant was never explicitly referred to as having a launch bay, it shares similarities with the launch bays of the NX class. The script of "Call to Arms" states that the room where Chief O'Brien was working on the mines was the Defiant's launch bay.
Dominion Headquarters on Cardassia Prime had at least three launch bays. A Cardassian patrol ship was sitting on launch bay 3-A in 2375. Damar told Worf and Ezri Dax of the launch bay's location, so they could escape execution by the Dominion. (DS9: "Strange Bedfellows")