The X-301 Interceptor was the Tau'ri's first attempt at developing a space-based combat vessel capable of engaging the Goa'uld. It was originally two Goa'uld Death Glider's obtained during Apophis' failed attack on Earth, before they were combined into one, the craft was modified by technicians at Area 51 and equipped with an Earth-based fire control system and arsenal, while leaving its Goa'uld propulsion system intact.
The X-301 leaves Earth's atmosphere.
The craft was designed for two pilots, and its unique technology didn't exert force against gravity so much as take inertia out of the equation, thus virtually eliminating the effect of G-forces. Intended as a platform from which to launch an attack against a Goa'uld mothership, the X-301 was equipped with stealth technology and two AIM 120A air-to-air missiles that could be armed with naquadah-enhanced warheads and modified with a shield-frequency modulator.
Though initial trials proved successful, during a live-fire test flight the vehicle unexpectedly veered off course and carried its two-person crew, Colonel Jack O'Neill and Teal'c, into space the result of a recall device installed by Apophis to punish any disloyalty by his followers. This rendered the craft unusable, stranding O'Neill and Teal'c in deep space until they could be rescued with the aid of the Tok'ra. (SG1: "Tangent")
The X-301's fate following their recovery is unknown, though Earth would not have possessed the ability to retrieve it until the launch of the Prometheus two years later. In any case, the idea of creating a working vehicle by modifying alien spacecraft was abandoned in favor of entirely Earth-built vehicles such as the X-302