A phase cannon was a phase-modulated energy weapon, a type of particle weapon which served as a successor to plasma cannons and as a precursor to the phaser of the 23rd and 24th centuries. The prototypes of ship-mounted phase cannons were first introduced by the Earth Starfleet in the mid-22nd century, designed as the primary defense of NX class starships and serving as a supplement for the lacking spatial torpedoes of the time. The first NX class vessel to test and actively use phase cannons in battle was the NX-01 Enterprise.
Designed as a starship-based version of the hand-held phase pistol, the phase cannon was rated for a maximum power output of 500 gigajoules. The cannons of NX class starships were mounted on retractable turrets which extended from the ship's hull when deployed and rotated as it was being targeted. Like phase pistols, phase cannons emitted a concentrated beam of energy that could be set at different yields. (ENT: "Silent Enemy")
The phase cannon assembly was equipped with multiphasic emitters and had a maximum yield of 80 gigajoules. Aboard an NX class vessel, the assembly was located on F Deck and could be accessed through a hatch near the torpedo room. (ENT: "Cogenitor")
When initially installed on the first NX class vessel in 2151, the phase cannons were located on the ventral side of the ship. Two were placed at the bow of the vessel, while one was placed at the aft on the ship's starboard side. (ENT: "Silent Enemy", "Fallen Hero") By 2152 the first vessel of this class, the NX-01 Enterprise, was outfitted to hold at least four cannons on the dorsal saucer section; two at the bow and two closer to the stern, with one on each of the catamaran-like sections. (ENT: "Shockwave, Part II", "Singularity") An additional ventral aft cannon was added on the port section of the NX class some time after the first cannons' installation. (ENT: "Future Tense", "Similitude") Two more cannons were installed on the ventral part of the saucer section, only closer to the bow than the first cannons. (ENT: "Bounty", "Storm Front, Part II") Yet two more pairs of cannons were added to the dorsal and ventral side of the nacelle pylons, near the impulse rockets, sometime prior to 2154. (ENT: "E²", "The Aenar")
Phase cannons were generally more powerful than spatial torpedoes and were therefore more effective in a firefight. Initially, a ship's phase cannons could not be fired while the vessel was at warp, as doing so would cause the weapon's particle discharge to destabilize the ship's warp field. This would result in serious damage to both of the ship's warp nacelles, and could possibly even destroy them. (ENT: "Fallen Hero") By 2152, Enterprise armory officer Malcolm Reed had corrected this problem as the ship was able to fire its aft phase cannon at warp while it was pursued by a Suliban fleet. (ENT: "Shockwave, Part II") Phase cannons took some time to charge when manually activated. This issue was resolved with the implementation of Reed's tactical alert, which brought the weapons automatically online after the alert was given. (ENT: "Singularity")
Despite their power, phase cannons were sometimes unable to penetrate the defenses of other alien vessels. Not only did they prove relatively powerless against the shields of the first vessel they were used against (ENT: "Silent Enemy"), but it would have also taken a sustained beam to punch through the hull of a D5 class Klingon battle cruiser. That was assuming, of course, that the battle cruiser remained still long enough, which was unlikely. (ENT: "Judgment") Likewise, the cannons could be easily taken out with a single photon torpedo shot from a Klingon Bird-of-Prey. (ENT: "The Expanse") Because of this, Klingons regarded the cannons, which they identified as "low-yield particle cannons", to be of little threat. (ENT: "Judgment")
Initial Test and Early Use
Enterprise was originally designed to carry three phase cannons. However, due to Enterprise's premature launch in 2151, Jupiter Station did not get the chance to install the cannons, though Enterprise was given one of the prototypes. On August 30th, 2151, Malcolm Reed and Trip Tucker were given the job of installing the prototype, as well as building two more from scratch. They were able to accomplish the installation -- two forward cannons, one aft -- in 48 hours, a job that would have taken the armory team at Jupiter Station at least a week.
The initial test of Enterprise's phase cannons was conducted on September 1st, on an asteroid. The first shot was only to have "shaved" a few meters off the top of a mountain peak, but the blast was so powerful that it formed a new crater within the asteroid. The resulting overload of the phase modulators caused a plasma recoil that blew out relays across decks C and D. Following this, it was determined that the blast yield of the shot was ten times what was expected. It was then that the crew realized that the cannons had been manipulated by a mysterious alien race.
When the alien beings attacked Enterprise, the cannons proved ineffective against the alien vessel's shielding. Reed and Tucker then caused another overload, this time intentionally, while using the gravity plating on C and D decks to absorb the plasma recoil. The resulting overload again increased the cannon's blast yield, which disabled the aliens' shields and allowed Enterprise to gain the upper hand. (ENT: "Silent Enemy")
In February of the following year, Enterprise used its aft phase cannon to disable the shields and engines of a Mazarite ship, although Enterprise had to drop to impulse to do so. Travis Mayweather would recount this incident to his brother, Paul, in January 2153. (ENT: "Fallen Hero", "Horizon")
Shortly thereafter, the forward cannons were used to disable a cloaked Suliban vessel hidden within a binary star system. While an assault team was on the ship acquiring information, the cannons were again used on the Suliban ship to collapse a corridor containing several Suliban, clearing the way for the assault team to escape. (ENT: "Shockwave, Part I")
Later, while escaping the Suliban Helix, Enterprise used its aft cannon on the pursuing Suliban cell ships while at warp speed. The cannons destroyed at least one of the ships. (ENT: "Shockwave, Part II")
In August of 2152, Reed proposed new tactical protocols that would increase the efficiency of the Enterprise's weapons, including the phase cannons. While under the influence of radiation emitted from a nearby singularity, Reed implemented the new protocols without Captain Archer's permission.
Later, with the rest of the crew having succumbed to the radiation, Archer and T'Pol attempted to navigate Enterprise away from the singularity as quickly as possible by piloting the starship through a field of debris. When the need arose to use weapons against a large meteoroid that was in the ship's path, T'Pol worried that the phase cannons could not be charged in time. However, when a smaller piece of the meteoroid collided with the ship, Reed's tactical protocols initiated and the phase cannons were automatically brought online. T'Pol then used the cannons to destroy the remaining meteoroids, allowing Enterprise to safely escape the singularity. Following this incident, Reed's new security protocols were made standard procedure. (ENT: "Singularity", "Cease Fire")
Later Uses and Applications
The following month, the cannons were used in an attempt to disable the engines of a Retellian freighter which had captured Commander Tucker. Although the cannons appeared to disable the freighter's port warp nacelle, it was merely a ruse by the freighter's pilot, Firek Goff, to disable the Enterprise's own warp engines. (ENT: "Precious Cargo") Later, Commander Tucker threatened to use Enterprise's cannons on Vulcan and Andorian vessels if they attempted to enter orbit of Weytahn. (ENT: "Cease Fire") Not long afterwards, a vessel crewed by noncorporeal beings were able to take Enterprise's cannons off-line and capture the ship, although Enterprise ultimately escaped regardless. (ENT: "The Crossing")
The ship's aft phase cannons were later used in defense against a group of Suliban cell ships which were pursuing Enterprise in an attempt to capture the time travel pod in the ship's launch bay. The cannons destroyed at least one cell ship; several Tholian starships took care of the rest. (ENT: "Future Tense")
The cannons were later used in battle against a Klingon Bird-of-Prey commanded by Duras, although they did negligible damage. (ENT: "Judgment") In March 2153, the cannons were used to disable the weapons of Arctic One, which had been taken over by the Borg. Later, after several spatial torpedoes were used to weaken Arctic One, a single, final shot from a phase cannon would destroy the transport. (ENT: "Regeneration") Later that same month, the cannons were used to destroy a decoy device which was generating a false Tellarite warp signature and preventing Enterprise from locating the Tellarite ship which had captured Captain Archer. (ENT: "Bounty")
During the Xindi incident, a phase cannon emitter aboard Shuttlepod 1 was used to destroy the locking mechanism of a Delphic Expanse sphere so the vehicle could gain entrance. Later, Enterprise fired its cannons at the sphere to lure an Osaarian pirate ship into close vicinity of Enterprise so Hoshi Sato could download information on the Xindi from the pirate ship's computer banks. Although the first attempt using a single, minimum yield blast from one cannon did not succeed, a second blast using both cannons destroyed the sphere's portal and got the Ossarians' to attack Enterprise, allowing Sato to successfully download the information they needed. (ENT: "Anomaly") The cannons were later used against two Xindi-Reptilian vessels who were attempting to retrieve their spy, Rajiin, from Enterprise. (ENT: "Rajiin")
Several months later, when Enterprise entered a polaric field and its hull was bombarded with nucleonic particles, the aft cannons were redirected towards the back end of the hull and used to blast away the particulates which had accumulated on the ship's launch bay doors. This allowed for the launch of the ship's shuttlepods, which were then used to tow the Enterprise a small distance, giving the larger vessel a strong enough momentum to clear the polaric field. (ENT: "Similitude")
The cannons were later used to quell attacking Triannon ships who were defending themselves against Enterprise while the starship was under the control of D'Jamat and his religious sect. After Archer reclaimed command of Enterprise, he had the cannons powered down to prove the starship was no longer a threat. (ENT: "Chosen Realm")
As Enterprise pressed forward into the Delphic Expanse in search of the Xindi superweapon, the ship came into contact with a number of debilitating spatial anomalies. One severe encounter in December of 2153 disabled all of the ship's weapons, including the phase cannons. Fortunately, the Andorian warship Kumari, under the command of Shran, was nearby to lend assistance. Shran assigned his tactical officer, Lieutenant Talas, to assist Lieutenant Reed in repairing the weapons. With Talas's help, the phase cannons were not only operational within a short period of time, but were also working at 94% efficiency. This was an improvement, as Reed was never able to exceed 93% efficiency from the cannons. Soon after the phase cannons were brought back on-line, they were used to disable two Xindi-Reptilian vessels, allowing the Kumari to seize the prototype of the Xindi superweapon. (ENT: "Proving Ground")
Shortly afterwards, the cannons were again used to disable a Xindi vessel, this time belonging to the Xindi-Primate Degra. He and his crew were then captured in order to gain information on the whereabouts of the Xindi weapon. (ENT: "Stratagem") The following month, the cannons were again used in an attempt to disable the engines of a Xindi-Insectoid vessel, but they proved ineffective. (ENT: "Hatchery")
The Enterprise suffered severe damage following a battle with Xindi-Reptilian and Xindi-Insectoid vessels near Azati Prime, resulting in the loss of the ship's weapons, including phase cannons. Following their repair, the cannons were used against an Illyrian vessel while an Enterprise boarding party stole the alien ship's warp coil. During the assault, T'Pol had Reed adjust the cannons to a narrow confinement beam and disable the Illyrian ship's power junction, allowing the boarding party to remove the warp coil and transport it and the party back to Enterprise. (ENT: "Azati Prime", "Damage") Nonetheless, at least two of the front cannons were not operational until two days after the Xindi attack. (ENT: "The Forgotten")Later, the cannons were deployed as defense against a group Kovaalan ships within a nebula. Disturbance from the nebula interfered with the cannons' targeting scanners, making it necessary for its target to be within close range. (ENT: "E²") Soon after, the Enterprise participated in a major battle in which the starship's phase cannons were used against Xindi Insectoid and Reptilian vessels as they escorted the superweapon away from the Xindi Council planet. At least one Insectoid ship was damaged after being struck by a phase cannon beam. (ENT: "The Council") A short time later, Enterprise's original forward phase cannons (coupled with photonic torpedoes) were used in an attempt to destroy the Xindi superweapon before it could be launched against Earth. Again, at least one Xindi-Insectoid ship was destroyed by the phase cannons during this battle. Also during the battle, phase cannons were used in defense against the lead Reptilian ship while a team of MACOs infiltrated the ship to rescue Ensign Sato. (ENT: "Countdown")
By the time Enterprise had completed its mission in the Expanse and returned to Earth in 2154, Starfleet, upon the recommendation of Captain Archer, had developed pulsed phase cannons. These advanced phase cannons were installed aboard the NX-02 Columbia. (ENT: "Home")During the Augment Crisis of May 2154, Captain Archer was trapped within the central core of Cold Station 12, where he was in danger of being infected with the thousands of deadly pathogens stored there. With interference from the core preventing his transport, the Enterprise's phase cannons were used to blow off the core's outer hatch, decompressing the core and blowing Archer into space. After being exposed to the vacuum of space for only an instant, Archer was transported back to the safety of Enterprise.
Later, Enterprise was able to stop the Augments from using pathogens stolen from the station to infect a Klingon colony. In retaliation, the Augments – aboard a stolen Klingon Bird-of-Prey – attacked Enterprise, disabling all weapons save for the ship's aft cannon, which was then used to destroy the Klingon ship's main plasma junction and disable the vessel. (ENT: "The Augments")
Enterprise later employed the cannons against a fleet of Vulcan warships which attacked the Starfleet vessel to drive it away from their planet, as per orders from Administrator V'Las. However, Enterprise proved to be no match for the Vulcans and was forced to retreat. (ENT: "Awakening") A short time later, the cannons were again used against the Vulcans to defend Andorian ships during a skirmish near Regulus, but the weapons were unable to penetrate the Vulcan ships' shields. (ENT: "Kir'Shara")
In November of that year, Enterprise used the cannons in an attempt to disable what appeared to be an Andorian warship which had attacked them without provocation. The cannons proved ineffective against the Andorian ship's shields, and even after Commander Shran supplied Enterprise with the coordinates for the attacking vessel's shield generator, the shields remained intact. The attacking vessel was ultimately forced to withdraw due to a fluctuation in its power grid, and it was later discovered that it was actually a drone ship controlled by the Romulans and capable of disguising itself as other vessels using holographic technology. (ENT: "Babel One")
The drone ship was able to simulate phase cannon fire using tri-phasic emitters, as evidenced by its attack on a Rigelian scoutship while disguising itself as Enterprise. Later, the real Enterprise intercepted the drone ship a second time, using phase cannons to disable its holographic emitters. Without its camouflage, however, the drone ship proved far too maneuverable for Enterprise to lock onto it in order to disable the drone's weapons. This forced the Starfleet vessel to shut down its own weapons and divert power to its hull plating. (ENT: "United") Enterprise would later employ phase cannons when facing off against two drone ships, but it was only through the assistance of Jhamel and the sacrifice of Gareb, two Aenar, that the drone ships were destroyed. (ENT: "The Aenar")
Later that month, Enterprise fired phase cannons at a Klingon Bird-of-Prey which had attacked the Starfleet vessel near the wreckage of a Rigelian freighter, but they were unable to prevent a Klingon boarding party from transporting aboard Enterprise and sabotaging its warp matrix. (ENT: "Affliction")
Both Enterprise and Columbia used their phase cannons against three Klingon battle cruisers that were attempting to eradicate Qu'Vat colony. Although Columbia managed to disable one of the Klingon ships, the cannons for the most part were ineffective against the battle cruiser's shields. Retaliation from the Klingons resulted in the loss of Columbia's weapons and Enterprise's aft phase cannons. Ultimately, however, a peaceful resolution was found and the colony was spared. (ENT: "Divergence")
In December 2154, Captain Archer, while under the influence of pheromones secreted by the three Orion slave girls aboard Enterprise, ordered Reed to fire the phase cannons at an attacking science vessel despite the fact that it was of no threat to Enterprise due to its low-yield weaponry. Because a single phase cannon hit would destroy the vessel, Reed refused to follow Archer's orders. Archer began to aim the cannons himself, but, as T'Pol had predicted, the science vessel ceased its attack and moved off. (ENT: "Bound")
In 1944 of an alternate timeline in which Earth's history had been altered as a result of the Temporal Cold War, Enterprise's original forward phase cannons were used in an attempt to prevent Shuttlepod 1, which had been hijacked by Silik, from reaching Earth. The cannons managed to damage the pod, but it was able to land on Earth nonetheless. (ENT: "Storm Front") Soon after, the cannons were used to subdue a squadron of Stuka dive-bombers, allowing Enterprise to destroy the facility housing the Na'kuhl and their temporal conduit and returning the timeline to normal. (ENT: "Storm Front, Part II")
In 2154, an Enterprise from an alternate timeline carried the same complement of weapons as Enterprise of 2154, despite the former vessel having been in existence for 120 years. Thus, the alternate Enterprise continued to use phase cannons, although they now fired a blue beam of energy rather than an orange beam. (ENT: "E²")
In an alternate timeline in which Earth was destroyed by the Xindi superweapon, phase cannons were still a Starfleet vessel's primary line of defense in 2165. In that year, Enterprise's cannons were used to knock out the engines of a Yridian ship. Later, Enterprise and the remaining Starfleet vessels used phase cannons against invading Xindi-Reptilian and Insectoid warships. Enterprise's cannons were disabled in the attack. (ENT: "Twilight")
Phase cannons were introduced in "Silent Enemy", twelve episodes into Star Trek: Enterprise's first season. Prior to this, Enterprise utilized plasma cannons (seen only once, in "Broken Bow"). The phase cannons were designed as an early version of the ship-mounted phaser technology seen on Star Trek: The Original Series, the Next Generation-era series, and the Star Trek films.
There is much confusion as to exactly how many phase cannons were installed aboard Enterprise during the course of the series. In "Silent Enemy", it was specifically stated that Enterprise had been designed to carry three cannons. The ports for these cannons were located on the ventral (bottom) part of the ship, with two at the bow and one at the aft (the latter seen in "Fallen Hero"). One of the cannons initially installed was a prototype built by Starfleet engineers; the other two were built from scratch by Tucker and Reed. However, in "Shockwave, Part II" (the opening episode for season two), phase cannon-like beams were fired from several areas on the dorsal (top) section of the ship. These weapons were later specifically referred to as phase cannons in "Singularity". This would seem to imply that at least two more cannons were built from scratch and Enterprise refitted to carry them.
We would also see phase cannons fired from the very front of the bottom part of the saucer section near the end of season two. There were also cannons seen fired from ship's warp nacelle pylons during season three, but whether these were also made from scratch or whether they were installed during the ship's refit in preparation to search for the Xindi superweapon is not clear.
There is a possibility that some of the phase cannons seen fired were the result of special effects errors. Another possibility is that some of the energy beams seen were actually the plasma cannons which Enterprise had utilized prior to the installation of the phase cannons, although the effect used was the sustained, orange beam associated with the phase cannon as opposed to the short, red bursts seen used by the plasma cannon. For this reason and those listed above, and because most were specified as being phase cannons, we must assume that all these energy effects shown were meant to be phase cannons. Then again, the Shuttlepods had similar effects for their weapons, but these were specifically referred to as plasma cannons in "Awakening".
Complicating matters, however, is Reed's line in "The Expanse" (the last episode of the second season) stating that a shot from a Klingon vessel had taken out "both forward phase cannons", after which the ship must go straight to firing torpedoes. Then there is T'Pol's line in "The Forgotten" (a third season episode) in which she states that Reed had been able to bring "both forward phase cannons online". These lines of dialogue suggest (although they do not confirm) that the ship still only had two phase cannons at the front of the ship; this, however, contradicts what was seen in previous episodes. Further complicating things is Reed's line in "The Augments" (a season four episode) in which he states "the aft cannon [is] online, but just barely". Again, this indicates the ship still only had one aft cannon as in the beginning despite visual evidence to the contrary. It also contradicts dialogue from later episodes (specifically "Divergence" and "Bound"), in which Reed uses the plural form for the aft cannons, proving the ship does indeed have more than one aft cannon. Also, rotating phase cannons are clearly seen on the far bow of the ship's ventral (in front of the originally-installed forward cannons) in "Storm Front, Part II", although we can assume they were installed sometime between "The Forgotten" (when there were apparently only two forward cannons) and "Storm Front".
The last reference to the ship's phase cannons occurred in "Bound" (ENT), set in 2154. It is unclear whether or not the cannons continued to be used afterwards, although the presence of phase pistols and phase rifles in the 2161-based holodeck scenes in "These Are the Voyages..." make it likely that phase cannons were used until at least that point. It is unknown at which point in time phase cannons were replaced, or if the laser weapons seen in the pilots for the original series were their immediate successor. It is unknown what other ships besides the Enterprise and Columbia were fitted with phase cannons.