Enterprise was launched from the Warp Five Complex on April 12, 2151 under the command of Captain Jonathan Archer. The launch occured three weeks ahead of schedule because of the need of Earth to return Klaang the Klingon to his homeworld of Qo'noS in time to recieve proper medical care. The early launch was strongly protested by Vulcan ambassador Soval, who believed humanity was not ready to explore space. He did manage to wrangle a concession from Starfleet, forcing Archer to allow the placement of Sub-Commander T'Pol on his vessel in exchange for Vulcan star charts. (ENT: "Broken Bow")
The early launch of Enterprise meant that it left spacedock somewhat unprepared: its spatial torpedoes were uncalibrated, and its phase cannons not even installed. The spatial torpedoes were calibrated in the heat of battle in May 2151 (ENT: "Fight or Flight"); the ship only survived because of the intervention of the Axanar. The phase cannons were not installed until September 2151 while Enterprise battled an unknown enemy (ENT: "Silent Enemy").
In March 2152, the ship's mission was cancelled when one of its shuttlepods appeared to have ignited the tetrazine gas within the atmosphere of the Paraagan II, killing 3600 innocent colonists. It was this event, plus its actions at other planets including P'Jem and Tandar Prime, that caused the Starfleet Command Council to recall Enterprise to Earth. Ambassador Soval recommended that Earth wait another ten to twenty years before trying another deep space exploration mission. Archer was able to convince the Starfleet Command Council and the Vulcan High Command to allow Enterprise to continue with a stirring speech about gazelles. (ENT: "Shockwave, Parts I and II")
In April 2152, Enterprise suffered severe damage after an encounter in a Romulan minefield (ENT: "Minefield"). Fortunately the ship was directed by a passing Tellarite vessel to an automated repair facility, though Enterprise was forced to destroy the facility to escape unscathed (ENT: "Dead Stop"). A plasma injector nevertheless failed shortly thereafter, necessitating a trip to the Kreetassan homeworld (ENT: "A Night in Sickbay").
After the Xindi attack on Earth in March 2153, Enterprise was recalled home. Arriving on April 24th, Enterprise was refitted and upgraded with the new photonic torpedoes, a Universal Translator update, and a new command center, and was relaunched on a new mission to the Delphic Expanse to search for the Xindi superweapon. Enterprise also took on board a detachment of MACOs for this mission. (ENT: "The Expanse")
The search for the Xindi was long and perilous, taking almost a year. Enterprise was in severe danger much of the time in the Expanse due to the presence of spatial anomalies generated by the spheres (ENT: "Anomaly"). It was discovered that insulating with trellium-D could protect the ship from the anomalies, but unfortunately trellium is hazardous to Vulcan neural pathways, and Captain Archer refused to let Sub-Commander T'Pol leave the ship (ENT: "Impulse").
In February 2154 Enterprise determined the location of the Xindi weapon and arrived in the Azati Prime system (ENT: "Azati Prime"). There the ship suffered additional damage due to multiple attacking Xindi ships; damage that required drastic actions on the part of Captain Archer to repair (ENT: "Damage"). Enterprise may have endured even more damage in the Delphic Expanse if not for the intervention of a future Enterprise, where the second ship travelled 117 years into the past when attempting to use a subspace corridor (ENT: "E²").
The Enterprise accomplished its mission to destroy the Xindi weapon successfully, though Captain Archer was presumed dead. The ship was returned to Earth by a Xindi-Aquatic cruiser following the end of the mission. (ENT: "Zero Hour")
For more information on the Delphic Expanse mission, see: search for the Xindi superweapon
Enterprise was the first Earth vessel to be rated with a transporter equipped for transporting biological organisms. However, the machine malfunctioned a number of times (ENT: "Strange New World", "Vanishing Point") and the preferred method of travel was still the shuttlepod. After trips in the pod, it was standard procedure for returning crew and passengers to utilize the decontamination chamber.
It was also the first Earth ship to be outfitted with Henry Archer's warp five engine, and as such was Starfleet's first "real" vessel of exploration. Enterprise was not so advanced in all areas, however. Unlike the Vulcan ships of its day, it did not possess tractor beams, merely grapplers.
This exploration was not entirely into unknown territory, as the ship was aided by the Vulcan star charts. However, it participated in several historically significant events, such as the discovery of the Temporal Cold War (ENT: "Broken Bow"), the return to Terra Nova (ENT: "Terra Nova"), continued involvement in Vulcan/Andorian hostilities (ENT: "The Andorian Incident", et al.), the destruction of the colony on Paraagan II (ENT: "Shockwave, Part I"), the encounter with the first noncorporeal life-form (ENT: "The Crossing"), the discovery of the lost human tribe in the Delphic Expanse (ENT: "North Star"), and the race to stop the Xindi superweapon (ENT: "The Expanse", et al.).
Enterprise also made Earth's first contact with numerous species, including:
- Andorians, June 2151 (ENT: "The Andorian Incident")
- Antarans, early 2153 (ENT: "The Breach")
- Arkonians, late 2152 (ENT: "Dawn")
- Axanar, May 2151 (ENT: "Fight or Flight")
- Borg, March 2153 (ENT: "Regeneration") Note: This first contact remained unconfirmed until 2365 (TNG: "Q Who?")
- Coridans, October 2151 (ENT: "Shadows of P'Jem")
- Enolians, late 2152 (ENT: "Canamar")
- Eska, November 2151 (ENT: "Rogue Planet")
- Ferengi, December 2151 (ENT: "Acquisition") Note: This first contact remained unconfirmed until 2364 (TNG: "The Last Outpost")
- Illyrians, early 2154 (ENT: "Damage")
- Kantare, December 2151 (ENT: "Oasis")
- Kriosians, September 2152 (ENT: "Precious Cargo")
- Kreetassans, January 2152 (ENT: "Vox Sola") Note: The ship later conducted a follow-up visit to the Kreetassan homeworld in mid-2152 (ENT: "A Night in Sickbay")
- Malurians, July 2151 (ENT: "Civilization")
- Mazarites, February 2152 (ENT: "Fallen Hero")
- Menk, September 2151 (ENT: "Dear Doctor")
- Osaarians, September 2153 (ENT: "Anomaly")
- Paraagans, March 2152 (ENT: "Shockwave, Part I")
- Retellians, September 2152 (ENT: "Precious Cargo")
- Risians, February 2152 (ENT: "Two Days and Two Nights")
- Romulans, April 2152 (ENT: "Minefield") Note: First visual contact was not made until 2266 (TOS: "Balance of Terror")
- Sphere Builders, December 2153 (ENT: "Harbinger")
- Suliban, April 2151 (ENT: "Broken Bow")
- Takret, September 2152 (ENT: "The Catwalk")
- Tandarans, January 2152 (ENT: "Detained")
- Tholians, late 2152 (ENT: "Future Tense")
- Triannons, November 2153 (ENT: "Chosen Realm")
- Valakians, September 2151 (ENT: "Dear Doctor")
- Vissians, early 2153 (ENT: "Cogenitor")
- Xindi, September 2153 (ENT: "The Xindi")
- Xyrillians, May 2151 (ENT: "Unexpected")
- Captain Jonathan Archer - Commanding Officer (CO)
- Subcommander T'Pol - Executive Officer and Science Officer
- Commander Charles Tucker III - Chief Engineer
- Lieutenant Malcolm Reed - Chief of Security and Tactical Officer
- Ensign Hoshi Sato - Communications Officer (COM)
- Ensign Travis Mayweather - Conn Officer (CONN)
- Doctor Phlox - Chief Medical Officer (CMO)
There are two alternate timeline versions of the ship known to exist.
In one alternate timeline, Captain Archer's brain was infected with interspatial parasites in October 2153. This parasite prevented him from forming any new long-term memories, and so he was relieved of command. Sub-Commander T'Pol recieved a field commision from Starfleet, becoming the ship's new captain. She continued the search for the Xindi superweapon.
In 2154 Enterprise learned the weapon was being built at Azati Prime. But as they drew close, the ship was attacked by two Xindi-Reptilian vessels. The ship suffered substantial damage: thirteen crew died, including Travis Mayweather, and twenty-three were injured. In addition, the starboard nacelle's was put out of commision, limiting the ship to Warp 1.7. By the time Enterprise reached Azati Prime at that speed, the weapon had been launched. They were able to follow it back to Earth through a subspace vortex, but their efforts were in vain and Earth was destroyed.
In 2155, Enterprise led one of several convoys of survivors to Ceti Alpha V, where humanity hoped to resettle to escape the wrath of the Xindi. When the ship arrived there in 2156, T'Pol turned command over to Commander Tucker; the ship's new responsibility was to patrol the Ceti Alpha system. The ship was upgraded with shields provided by General Shran of the Andorian Imperial Guard.
In 2165, Enterprise was attacked by Xindi forces that had finally located Ceti Alpha. Archer and T'Pol vaporized the ship in a subspace implosion, thus preventing the parasites in his brain from ever having infected him, creating a new timeline. (ENT: "Twilight")
In a different alternate timeline, the ship's trip through a subspace corridor from the Kovaalan nebula to the Xindi Council planet in February 2154 would have sent it to the year 2037. The particle wake from a damaged impulse manifold caused the corridor to shift in time. Unable to return to the present, Captain Archer decided to wait in the Delphic Expanse until the ship could stop the Xindi destroyer/probe from attacking Earth.
To survive for all that time, Enterprise forged alliances with other species, trading its advanced technology for food and supplies. The ship even acquired alien crewmembers, such as Archer's wife Esilia. With time, the ship acquired advances from other races as well. By 2154, its atmosphere processors had been doubled in effeciency, it acquired an isomagnetic collector from the Ikaarans, and it had had a tractor beam installed. In addition, Haradin traders provided the technology to upgrade the plasma injectors and allow the ship to reach Warp 6.9 for a brief time, but the ship's injectors were too old to take the stress, and so thet couldn't utilize the technology.
By 2153 all of the original crew had died except for T'Pol. Lorian was in command of the ship, Karyn Archer was executive officer and pilot, and Greer was tactical officer. Enterprise tried to stop the Xindi probe from being launched at Earth, but Lorian gave the order to ram it too late, and the probe departed. In 2154, Enterpise rendezvoused with the Enterprise of that time period just before it entered the corridor.
Lorian provided Archer with the Haradin specifications, but T'Pol intervened, showing that performing the upgrade was too dangerous. She suggested Enterprise upgrade its impulse manifold to reduce particle wake, but Lorian refused to let Archer carry out the plan; he stole the 2154 ship's injectors to use them himself. The two Enterprises deadlocked in space battle, and Lorian eventually relented and agreed to follow Archer's plan; Archer's Enterprise made it safely through the corridor.
The fate of Lorian's Enterprise is unknown. It may have been destroyed by the Kovaalans it was fighting at last sight, it may have escaped, or it may have been erased from history by allowing the 2154 Enterprise to make it through the corridor. (ENT: "E²")