The Intrepid was a Space shuttle used by the Tau'ri in an alternate timeline.

Alternate timeline

• In the alternate timeline where the Stargate Program never existed due to Ba'al going back to time and ensuring that the Stargate never reached the United States, the Intrepid was on a mission when the thrusters malfunctioned, sending the orbiter into a decaying orbit. An astronaut named Dr. Samantha Carter attempted to save the orbiter when the crew abandoned it. However, the Intrepid crashed over an ocean, and Carter's body was never found, but she was deemed a hero. (SG1: "Continuum")

Behind the scenes

Officially, there is no real life spacecraft that goes by the name "Intrepid".