Operation Fort Knox Operation Fort Knox was the name that Captain Kathryn Janeway gave to the mission to retrieve a transwarp coil from a Borg sphere in 2375 . While planning the theft of the transwarp coil , Captain Janeway used Fort Knox as a metaphor to explain the scale and the level of security around the prize they sought . Planning . After studying a Borg data node containing tactical information regarding the movements of Borg vessels , Seven of Nine presented the information to Captain Janeway , Commander Chakotay , and Lieutenant Commander Tuvok in astrometrics . When she pointed out three Borg cube s along their current route , Janeway noticed another vessel , not far from their present location . Seven determined the vessel to be a badly - damaged Borg sphere , heading back to Borg space at low warp . It was then that Janeway got the idea to assault the sphere and steal a transwarp coil . The mission briefing took place shortly thereafter , during which Janeway decided on the name for the mission : " Operation Fort Knox " , after the impenetrable 20th century Earth facility . A plan was decided on in which they would head for the sphere and use a diversion to allow an away team to beam aboard undetected . The away team would then steal the coil and return it to " Voyager " . Chakotay recommended they run holodeck simulations of the mission , in order to cover every possible contingency as Lieutenant B ' Elanna Torres offered some advice on masking the ship ' s warp trail . The plan was agreed on , and the briefing concluded . Preparation . In preparation , the crew of the ran several simulation s , testing various strategies against the Borg . The plan involved Tuvok and Ensign Harry Kim making their way to the sphere ' s shield generator s and detonating spatial charge s , while Janeway and Seven of Nine proceeded after the transwarp coil . However , the initial simulations failed , as the away team fell twelve seconds behind schedule , allowing the Borg the two minutes they needed to regenerate their sensor grid and beam over to " Voyager " . However , while reading some of her parents ' field notes about the Borg , Seven of Nine discovered a method of hiding within a Borg vessel for prolonged periods of time . The bio - dampener , created by the Hansens , would cloak the away team ' s life sign s by emulating the environment of the sphere , thus allowing them to complete their mission . Execution . The first part of the plan was put into effect ; a remote - piloted shuttlecraft was flown towards the Borg vessel emitting false sensor readings indicating there were three lifeform s on board . The intention was to allow the Borg to capture it , and , while the sphere ' s shields were down , give the away team an opportunity to beam in . This , however , did not go according to plan as the Borg did not consider the shuttlecraft a threat and simply ignored it . The shuttle needed to appear more of a target to the Borg . Therefore , Janeway ordered Chakotay to have the energy output of the shuttle ' s warp signature increased . The Borg took the bait and the sphere ' s shields were lowered , allowing the away team the opportunity to beam in . From there , the mission went according to plan , with one unexpected turn of event . Tuvok and Kim made their way to the shield generators and planted their spatial charges in the appropriate places , while Janeway and Seven arrived at the transwarp coil and planted transporter pattern enhancer s around the device , in preparation for transport . The spatial charges were successfully detonated and the coil beamed aboard " Voyager " . The away team then headed back to the transport co - ordinates for beam - out . However , " en route " to the transport site , Seven of Nine was contacted by the Borg Queen and told that " Voyager " would be destroyed unless she rejoined the Collective . Before Janeway could do anything , a force field was erected and she was forced to leave Seven behind . Aftermath . Although the transwarp coil was successfully taken from the Borg , Seven of Nine had remained behind . Refusing to accept the idea that Seven left willingly , Janeway ordered the " Delta Flyer " be equipped with the transwarp coil and a rescue mission was launched in an effort to bring Seven back to " Voyager " . The mission was ultimately successful when Seven was retrieved from the Borg unicomplex . Afterwards , the transwarp coil propelled " Voyager " an additional 20 , 000 light years closer to the Alpha Quadrant before giving out , cutting roughly fifteen years off her journey . ( )