Quantum slipstream drive

Quantum Slipstream Drive is a propulsion system not too dissimilar to transwarp drive, in which it takes ships at speeds higher than those permitted by even the most advanced engines.

The technology was created around the 2370s by a species in the Delta Quadrant. The USS Voyager was the first Federation vessel to achieve slipstream velocity, but as they had little experience with it they could not keep up with the rapidly changing quantum field. It took Starfleet scientists many years to perfect the usage of the slipstream technology, finally making a solid breakthrough in 2403.

Many starships on deep space assignment were equipped with the drive, in order to facilitate a quicker journey back to port, and in case of emergency. Originally, the drive was kept solely within the Federation, and with the Romulans and Klingons struggling to duplicate this success, a joint scientific research project was launched, where other possibilities were thought of including transwarp drive.

Ultimately, transwarp became impossible to achieve, so the Federation and her allies reverted back to quantum slipstream, due to their advanced knowledge of it. It was so successful in fact, that ships continued to use it up to 200 years later, when it was installed on the USS Pioneer in 2597.