A maintenance bay was an area of a starship, space station, or planetary base where larger vehicles such as shuttlecraft were repaired or serviced. The primary coolant tanks of Academy flight trainers could only be refilled in a maintenance bay. In 2368, while wondering why Wesley Crusher had opened the coolant interlock on his flight trainer, Jean-Luc Picard noted this, concluding that it was unlikely that Crusher had done so with that goal in mind. (TNG: "The First Duty" )