Null Space Catapult
The subspace catapult is an extremely advanced piece of propulsion technology that was designed and built by Tash, a stranded Traquel alien who was attempting to return home after accidentally passing through an unstable wormhole. Faced with the prospect of a lonely 10-year journey to reach his home, Tash diverted his efforts into the construction of a propulsion device that would drastically reduce his journey time.
The mechanics of the device are quite simple for such an advanced machine; when it is operated, a graviton surge is directed through the projectors onto the hull of the ship. This serves to propel it into a layer of subspace known as null space, where it stays for a period of time, often a matter of hours, during which time it traverses vast distances of 'real' space - theorized by Tash to be anything up to 1000 light years.
The catapult is powered by a tetryon reactor and has immense arms which support graviton projectors. Six projectors are supported on each arm, which when activated produce a blue field that encompasses a ship before it is transported into null space. The vessel, which is positioned between the arms, is held by the beams and then 'catapulted' into subspace. The graviton field can be set at different levels to determine the distance a ship is transported.
When the crew of the U.S.S. Voyager NCC-74656 first discovered the catapult in 2376, they immediately offered assistance to Tash, recognizing a kindred spirit in his plight to return home. Tash was grateful for their aid, and offered them the use of the catapult once he had completed his pioneering journey.
After the crew of Voyager refined the catapult's operation, Tash made his first manned flight. This allowed him to travel 5000 light years - which far exceeded his initial expectations - although he was forced to re-adjust his vessel's shields enroute to prevent the outer hull from being torn away.
Improving the journey
Following this successful journey, Tash sent Voyager a series of design modifications to improve its operation. After further testing, Voyager utilized the catapult, and traveled through 30 sectors of space in less than one hour, cutting three years off their journey time.
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