In [#100 Timeless], Kim and Chakotay travel in the Delta Flyer to the Alpha Quadrant but everyone on Voyager is killed. In 2390, Kim and Chakotay steal the Delta Flyer from a Federation shipyard and set out to change history.

Voyager engages the quantum slipstream drive (adapted from Arturis' drive, obtained in [#94 Hope And Fear]) in order to travel swiftly straight back to the Alpha Quadrant. The ship is preceded by the Delta Flyer, with Chakotay and Kim on board. It is Kim's task to transmit phase corrections to Voyager to keep the ship within a properly stable slipstream.

Voyager's bridge's viewscreen, showing the Delta Flyer flying ahead of Voyager in the quantum slipstream

However, Kim makes an error and while the Delta Flyer travels on to the Alpha Quadrant, Voyager falls out of the slipstream. Voyager crashes on an ice-planet near the Alpha Quadrant, killing all aboard (pictured).

In 2390, fifteen years after the tragic event, Kim and Chakotay put into action a secret and daring plan to change history. Having stolen the Delta Flyer from a Federation shipyard, they (along with Chakotay's lover, Tessa) go to the ice-planet and salvage the Doctor. He agrees to obtain data from Seven's Borg interplexing beacon so that Kim, using a salvaged Borg temporal transmitter, can transmit the correct phase corrections back in time and, not only avert the disaster, but also bring ship and crew home safely.

in the aft compartment of the Delta Flyer, the Doctor contemplates surgery on the thawed body of the long-dead Seven

Chakotay and Kim are pursued by Starfleet, being wanted for high treason and conspiracy to violate the Temporal Prime Directive.

Unable to correct his original error, Kim settles for transmiting a phase correction back in time which disperses the quantum slipstream entirely. He manages to do that just as the Delta Flyer is destroyed by a warp core breach after breaking free of the tractor beam locked on by the pursuing USS Challenger.

the Delta Flyer breaks free from the USS Challenger

the destruction of the Delta Flyer in 2390

Back in 2375, both Voyager and the Delta Flyer are thrown out of the slipstream, effectively erasing the future - they are safe, though still in the Delta Quadrant.

In the revised future neither Voyager nor the Delta Flyer sustain damage, and the flight in the quantum slipstream was not wholly a failure as they end up ten years closer to home.