Turbolifts

Intraship personnel transport is provided by the Turboelevator (Turbolift) System. As a starship's internal transportation system, the Turbolift provides rapid access to virtually all parts of a vessel. The system is comprised of two parts: Turbo-shaft and Turboelevator. This network of inductively powered transport tubes allows high-speed personnel movement throughout the habitable volume of the ship.

The Turbo-shaft is a network of interconnected hollow tubes - running vertically and horizontally - extending throughout a vessel. Redundant links are often built allowing tubes to be closed for periodic maintenance and for areas of high flow through traffic allowing bypass routing. From the main Turbo-shaft, shorter tubes branch off - each ending with a Turbolift Station (a door accessing the Turboelevators), so that stationary or parked Turboelevators do not block the Turbo-shaft. There are frequently several Stations per deck, widely spaced. The network is designed to provide alternate access routes to all decks, permitting alternate routing during times of heavy system usage. Normally, Turbo-shafts run between compartments, and are enclosed by bulkheads. However, in some starship designs, multi-level compartments (such as the Rec-Deck and Cargo Bays) the Turbo-shafts are free-standing, giving the impression of cylindrical facetted white pillars, through whose glowing translucent surface Turboelevators can be seen rising and descending. The design philosophy also minimizes the effect of any given single malfunction on overall system performance.

There is more than one Turboelevator for every Turbolift Station. With several Turbolift Stations per deck, most vessels possess upwards of forty Turboelevators. All operate under the constant guidance of the Main Computer, which shunts vacant Turboelevators around so that no Station is without a Turboelevator longer than twenty seconds. For example, if one was to get into a Turboelevator in the Cargo Bay and travel to the Bridge, the Bridge Turboelevator would be shunted automatically downline and another Turbolift would be shunted to the just vacated Cargo Bay Station. This is to both to clear a Bridge Station and to refill the vacated Station as quickly as possible. The Main Computer would guide the occupied Turboelevator along the quickest route, while the empty Turboelevator would travel at a more leisurely rate, so as to avoid blocking an occupied Turboelevators.

Operation is simple. Upon entering a Turboelevator, the passenger(s) state his/their destination(s) verbally. This is picked up by the Turboelevator's Intercom and programmed into the Computer. For confirmation, the stated destination will appear written on the graphic display on the rear of the Turboelevator. Showing a plan and elevation of the entire system, the progress of the Turboelevator may then be observed as a lighted dot along the pathways of the Turbo-shaft network. For multiple destinations, the Turboelevator will chose a route which is tangent to all destinations.

For Decks with more than one Station, each Station has been assigned a number which, given with the deck letter, identifies the destination (eg: D-3, F-2). For Turbolift Stations within a compartment or complex, simply
state that compartment/complex's name (eg: Bridge, Sickbay, Main Engineering). Voice recognition protocols allows the computer to identify individual crewmembers. With user identity know, the computer can access the crewmen's duty roster. So when a crewmember comes on duty and gives a destination like "Deck 15, Science Lab" the computer recognizes the users voice and knows which science lab the crewmen works. It then sends the Turbolift to the station closest to this lab. On occasion, the computer may ask for a clarification or more exact destination. It also prevents unauthorized users from traveling to sensitive areas. Under Alert conditions, Turbolifts can detain intruders and transport them to the closest Security Station or holding area to be met by Security personnel. Upon receipt of the user's destination, the individual lift car queries the network control computer and receives instructions on optimal route. Under Alert conditions, the Turbolift system prioritizes personnel movement depending on rank and duty. This allows priority personnel the fast and most direct routing to their destinations, while lower priority personnel and non-crew personnel may be shunted around if in transit or wait longer periods for turbolift access. Overrides allow the Operation Officer, Security Officer and Damage Control Officer access to Turbolift programming to change priorities.

Each Turbolift car consists of a lightweight duranium composite framework supporting a cylindrical personnel cab fabricated from microfoamed duranium sheeting. Motive force is provided by three linear induction motors mounted longitudinally within the cabs exterior frame. These induction motors derive power from electromagnetic conduits located along the length of each Turbo-shaft and are capable of accelerations approaching 10 m/sec2. For crew comfort, an internal dampening matrix at the base of the cab reduces (but does not eliminate) the acceleration effects of Turbolift motion. Around the perimeter of the cab are ten magnatomic emergency expansion brakes. There are also three zero-power grappling brakes located on the top of the cab. In the event of power loss or computer malfunction, these brakes are deployed when the power to their retainers is lost, allowing the brakes to deploy. They are held in place, at safety, by powered retainers. Should power be lost, the retainers fail, and the brakes deploy.

During emergencies, the Turbolift cars can be used as lifeboats. During an evacuation, the Turbolift system expedites personnel to the normal lifeboats for evacuation. However, should the computer determine that the lifts occupants will not be able to make it to a lifeboat section in time, the cab is routed to an outside exit for jettisoning. Once ejected, the Turbolift, now lifeboat, extends to one and a half its original height, increasing the internal volume to comfortable support eight passengers for up to four weeks. Located on the bottom of the cab is the emergency propulsion system and lifeboat survival equipment. On the top is the emergency beacon, sensors and landing parachute. The interior is equipped with compact food rations, and other standard survival equipment.

An average of forty turbolift cars are in service at all times on a Gabriel Class ship. During times of peak usage such as a shift-change, this number can be doubled with only a 22% reduction in overall system response time. On average less then 5% of the Turbolifts are out of service or undergoing routine maintenance. There are several stand-by cab alcoves located outside high usage areas allowing extra cabs to be positioned to frequent usage. These areas normally include the Bridge, Main Engineering, Security, Main Shuttlebay, CIC, Sickbay, Forward Lounge, Rec-Deck and the Main Air-lock. While docked at a Starbase, the Turbolift system can be linked directly to the support facility's own Turbolift system. This is accomplished by means of a connect point located next to the Main Air-lock and Main Gangway. When so linked, turbolift cars can travel freely between the Starbase and the ship.

Bibliography-

Star Trek The Next Generation Technical Manual – by R. Sternback and M. Okuda
Starfleet Dynamics - John David Schmidt
Jackill's Starfleet Reference Manual, Ships of the Fleet - Volume One (Revised) - by Eric Kristiansen

Author – Chief Engineer Lt. Wayne N Snyder
Date: August 29, 1998