Inside a standard warp nacelle
The Nacelle tube is a space found within a Federation starship warp nacelle used in the maintenance and monitoring of the system's operation.
Aboard the Template:ShipClass USS Enterprise-D, the nacelle tube included a small control room, which was found on deck 25, at the rear of the nacelle, near the plasma injectors. The control room was accessible in nominal conditions by Jefferies tube only and was comprised of two levels, with isolation doors providing access to the interior of the nacelle itself. The isolation doors could be opened with the protection of a one-way force field. The doors, however, could only remain open for 90 seconds to prevent force field degradation and the release of drive plasma.
In 2370, the starboard nacelle tube control room was manned by Lieutenant Nara and Lieutenant J.G. Daniel Kwan. On stardate 47622.1, Kwan committed suicide by jumping through the force field and into the plasma stream, echoing a similar event that occurred during the construction of the ship in 2363, when Lieutenant J.G. Walter Pierce committed suicide through similar means. (TNG: "Eye of the Beholder").
- The nacelle tube was originally conceived of by "Eye of the Beholder" writer Brannon Braga as a long catwalk that ran the length of the nacelle. While the set was ultimately constructed as a two-level room, augmented with a matte painting, the catwalk would eventually appear in Star Trek: Enterprise in the appropriately titled episode "The Catwalk". While not explicitly stated in dialog, the location of the nacelle tube can be identified by signage (clearly placing it on deck 25 starboard) and by the matte painting vista of the nacelle interior, facing forward to the bussard collector. Parts of the nacelle tube set were later incorporated into the upper level of the engineering set used on Star Trek: Voyager.