- For other uses, see Sentinel.
The USS Sentinel (NCC-1733-B) was a Sovereign class heavy explorer launched by Starfleet in late 2375, shortly after the conclusion of the Dominion War. She was outfitted with an experimental interspatial warp drive (noticeable by the modified warp nacelles), and was under the command of Marcus Brennan, a seasoned veteran of the fleet. Her XO was Commander Patrick Cates. After launch, she was testing her engines near the Titan System. Upon entering orbit of Rkar N'ra, Captain Brennan led an away party to the surface and discovered an ancient transphasic pulse generator.
Returning to the ship in an "agitated state", Captain Brennan and the away party were quarantined in sickbay while Commander Cates investigated the Vanguard complex. The signals broadcasted from the pulse generator caused the ancient machinery to activate, launching thousands upon thousands of the Kam'Jahtae fighters. Shortly after, Starfleet lost contact with the Sentinel until the USS Typhon received word from a Romulan commander that the Sentinel was responsible for damaging several D'deridex class warbirds operating near Rkar N'ra. For most of the Titan System Incident, the Sentinel would stay in orbit of Rkar N'ra while the transphasic pulse generator expanded the subspace rift.
Towards the end of the conflict, the Typhon finally found the Sentinel leaving orbit of Rkar N'ra and heading towards the subspace rift. Captain Brennan's morals were warped by the Hur'q/Kam'Jahtae mind control, and he intended to take the ship into the rift. Despite heavy damage inflicted by Valkyrie fighters, the Sentinel continued towards the rift. With the engines disabled and the ship drifting closer, Captain Brennan activated the self-destruct sequence. The Sentinel was destroyed while escape pods were launched. Thanks to the efforts of Ensign Ryan Cooper, the escape pod carrying Brennan and the transphasic pulse generator was tractored into the rift, and the Hur'q were forced back into their prison. (TNG video games: Armada, Armada II, Invasion)