|Ship Name:||USS Excalibur|
|Type:||Enhanced scientific/diplomatic explorer|
The Excalibur survived an attack by the Borg during a night shift sometime prior to 2368. Several members of the crew, including Marika Wilkarah, were assimilated in the encounter. (VOY: "Survival Instinct")
In 2368, the Excalibur was undergoing a major refit and repair at Starbase 234. It was commandeered by Captain Jean-Luc Picard to serve in a Starfleet blockade of the Klingon-Romulan border during the Klingon Civil War. During that mission, it was commanded by Commander William T. Riker, with Lieutenant Commander Geordi La Forge as First Officer since the Excalibur's crew had been reassigned due to the extent of the refit. (TNG: "Redemption II") Source: USS Excalibur (NCC-26517) article at Memory Alpha, the canon Star Trek wiki.
Following the war, command of the Excalibur was given to Captain Morgan Korsmo, following the destruction of his previous vessel, the USS Chekov, by the Borg in late 2367. Lieutenant Commander Elizabeth Shelby, following Korsmo from the Chekov, was assigned to the Excalibur as First officer. In 2369, the Excalibur stopped at Starbase Deep Space 9 before embarking on a diplomatic mission to Vigan Delta V. Later that year, the Excalibur encountered Borg Cube 45208 and a number of Excalibur personnel were assimilated, including Lieutenant Marika Willkarah, who had served on Excalibur for just over a year.
In 2371, the Excalibur went to Lintar IV to rescue Worf, William T. Riker, Deanna Troi, and Alexander Rozhenko from the Romulan Sela, who was holding them prisoner. Later that year, the Excalibur went to Argelius II to pick up Burgoyne 172, the ship's new assistant Chief Engineer. On stardate 50391.5, Captain Korsmo was killed during the Battle of Sector 001 against the Borg.
His last order to Commander Shelby was to see to the safety of all hands. Following the vessel's refit, command of the Excalibur was given to Captain Mackenzie Calhoun, who was assigned to offer assistance and humanitarian aid to the residents of Sector 221=G, the former Thallonian Empire. Soon after beginning her mission, the Excalibur answered a distress call from the freighter Cambon and assisted in repairs. This eventually led to the Excalibur being at the forefront of a hostage situation on the Nelkarite homeworld when a Nelkarite leader was willing to let the hostages and thousands of her own people die if the Federation did not meet her demands. The Excalibur went to meet with members of crew that had responded to a distress call from the freighter Kayven Ryin. Upon arrival, debris of the Kayvin Ryin and the shuttlecraft USS Marquand was found. The Excalibur followed an ion trail to the planet Thallon, where the vessel rescued a thousand Thallonians before the planet was destroyed by the hatching of the Great Bird of the Galaxy. In 2374, the Excalibur traveled to Zondar, where Calhoun was seen as the planet's foretold savior. The Excalibur defended Zondar from the approach of the Redeemers, a race of religious extremists who believed in the conversion of planetary populations to the worship of their God, Xant, or, failing conversion, death to the world's population. The Excalibur stayed at Zondar for a time so that Lieutenant Soleta could perform some archeological research. The Excalibur soon received orders to travel to Momidium and retrieve Lieutenant Robin Lefler's mother, Morgan Primus, who had been imprisoned there for five years for trespassing. The Excalibur next went to the planet Ahmista, where the crew had an encounter with the powerful beings known as the Prometheans, whose weaponry, in the hands of the insane Tarella Lee, was used to annihilate Ahmista's native population. The Excalibur soon met with the USS Seidman to transfer the casualties. The Excalibur stayed on assignment in Sector 221-G during the opening days of the Dominion War. In mid-2374, the Excalibur attempted a time-traveling "slingshot" maneuver, and found themselves 18 months past their starting date.
The Excalibur emerged from her time-traveling adventure in late 2375, in the closing days of the Dominion War. Soon after the end of the war, Excalibur saved the survivors of the USS Independence, including passenger William T. Riker, from an attack by a trio of Romulan warbirds. The Excalibur warped to Deep Space 4, where Admiral Alynna Nechayev placed Riker in temporary command of the Excalibur, while Calhoun went on special assignment. The Excalibur went to Narobi II to investigate reports of Romulans working with the Narobians. Once there, the Excalibur was disabled by a Narobian virus and the Romulans boarded the ship, but the Excalibur crew was able to retake the vessel. The Excalibur then went to General Gerrid Thul's Dyson Sphere and was able to rescue Captain Calhoun and Captain Jean-Luc Picard, where they were both on undercover assignments. In late 2375, the Excalibur sent the shuttlecraft Marquand II to the planet Montos on a diplomatic mission, where the away team encountered Kalinda, the missing sister of Ambassador Si Cwan, and Captain Calhoun's son, Xyon, who was in command of the small vessel, the Lyla. The Excalibur tracked the Marquand and the Lyla to The Quiet Place and rescued her wayward crew members from the Dogs of War and the Redeemers. Soon after, the Excalibur went to the planet Fennar to stop a Redeemer attack on the planet. Captain Calhoun reluctantly decided to help the Redeemers stop the Black Mass, a voracious entity that consumed entire solar systems and was heading directly for the Redeemer homeworld. Soon after, the Excalibur engaged the Black Mass, but was overwhelmed and had to retreat. The Excalibur and the Lyla lured the Black Mass into a black hole, which destroyed most of the insatiable entity. Soon afterwards, the Excalibur was destroyed by a Narobian virus that was planted in the ship's computer during the Double Helix crisis. Captain Calhoun was presumed to be killed in the explosion.