Freighter convoy Edit
The Cardassians prepared seven convoys to transport medical supplies and relief workers over a period of a week. Among the ships in these convoys were vessels of this design. Because the Cardassians didn't have the warships available to protect the relief convoy, they asked for Starfleet protection. The USS Defiant was assigned to escort Convoy 6.
On stardate 49648, the Defiant was engaged by a group of Klingon raiders that were attacking the freighters, an engagement which eventually set the stage for the apparent, and inadvertent destruction of a Klingon civilian transport ship. (DS9: "Rules of Engagement")
Transport ship Edit
This transport ship evacuated Quatal Prime in 2373 after Michael Eddington, the leader of the Maquis, poisoned the planet's atmosphere. The Maquis then disabled the transport, causing it to lose power and slowly spiral down toward the atmosphere of the planet.
The transport was quickly rescued by the Defiant, which towed it free of the gravitational pull of the planet. After some rudimentary repairs were made by a repair team from the Defiant, the transport was able to limp back to Cardassia. (DS9: "For the Uniform")