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Template:Fac A cloaking device is a form of stealth technology that uses selective bending of light to render a starship or other object completely invisible to the electromagnetic spectrum and most sensors. It has been encountered in varying forms over the centuries.


Early cloaking technology

One of the earliest encounters with cloaking technology was in May 2151, when it was utilized by some agents of the Suliban Cabal to covertly approach the Enterprise and thus kidnap Klaang the Klingon from the ship's sickbay. The Suliban used cloaking devices on many of their ships, including the cell ships and the stealth-cruiser. It is likely that the use of cloaks by the Suliban was temporally anachronistic, and the technology had been given to them by their mysterious benefactor from the 29th century. (ENT: "Broken Bow")

During a battle near a Suliban Helix in a class seven gas giant, Enterprise managed to capture a cell ship. Chief engineer Charles Tucker III studied the device in his spare time, and in 2152 the ship was used to mount a rescue mission. Unfortunately, Tucker's experience with cloaking technology was somewhat limited and he accidentally dosed his hand with the particles the ship used to generate the cloaking effect, temporarily rendering it invisible. (ENT: "Broken Bow", "The Communicator")

The Suliban cloaking devices seem to use a form of particle radiation to to alter the molecular structure of matter in order to allow light and sensor signals to pass through it. This explains why Mr. Tucker's hand was cloaked without any external power sourse or gravity field surrounding it. It would also explain why the quantum beacons could detect such cloaked vessels.

Enterprise learned how to penetrate a Suliban cloaking device in March 2152, when the temporal agent Daniels explained how to construct a quantum beacon so that Enterprise could reveal the location of the cloaked stealth-cruiser responsible for the destruction of Paraagan II. (ENT: "Shockwave, Part I")


Romulan bird-of-prey cloaking

Enterprise was also responsbile for an encounter with another organization that used stealth technology, the Romulan Star Empire. In April 2152, the ship blundered into an entire cloaked minefield protecting a Romulan-claimed planet. The quantum beacons proved effective against the minefield, but when two birds-of-prey suddenly arrived, Enterprise was not able to pentrate their more advanced cloaks. (ENT: "Minefield")

The Return of the Cloak

By the 23rd century, the very idea of practical invisibility was considered only theoretically possible as the amount of power required would be enormous. This was proven untrue in 2266 when the USS Enterprise (NCC-1701) encountered a Romulan bird-of-prey that used the device to cross the Romulan Neutral Zone and wipe out several Earth Outpost Stations. The Enterprise was able to defeat the bird-of-prey in battle, partially because the cloaked ship was still visible to tracking sensors, but there was no doubt the device itself had been a success. (TOS: "Balance of Terror")

The cloaking device soon spread to the Klingon Empire as well, by virtue of an alliance between the two militaristic powers. One of the first Klingon vessels to be equipped with the device was the IKS Klothos, whose Commander Kor used it to great effect at the Battle of Caleb IV. Soon, the device was standard on almost all Klingon vessels, such as the B'rel-class bird-of-prey. (Star Trek III: The Search for Spock, DS9: "Once More Unto the Breach")

The Federation and the cloak


The improved Romulan cloak

Ever since the Enterprise's encounter with the bird-of-prey in 2266, the United Federation of Planets has had a strong interest in cloaking technology.

In 2268, when the Federation learned that the Romulans had developed a new and improved cloaking device, that even tracking sensors could not pick up, that posed a threat to the security of the Federation. On stardate 5027.3, Starfleet Intelligence sent the Enterprise on a covert mission across the Romulan Neutral Zone to acquire the new cloak. The mission was a success, and Starfleet was presumably able to develop a way to penetrate the new cloak. The Federation also presumably acquired a cloaking device from a captured Klingon bird-of-prey, dubbed the "HMS Bounty", in 2286. (TOS: "The Enterprise Incident"; Star Trek IV: The Voyage Home)

However, due its peaceful nature and highly principled devotion to exploration, Starfleet made very little of the cloaking device, so it was not much of a concession in 2311 when the Federation agreed to forgo any further use of cloaking technology with the signing of the Treaty of Algeron. The Bajoran Provisional Government also outlawed cloaking devices, stating that the possession of such a device is highly illegal. (TNG: "The Pegasus"; DS9: "Profit and Loss")


Quark's cloaking device

In 2370, Quark illegally acquired a small cloaking device that was, as he put it: 'not in the best of condition', but it 'will work for about 15 minutes.' Initially intending to sell it, Quark instead installed in the central engine core of a Cardassian shuttle, piloted by Natima Lang, to help the ship escape Deep Space 9 undetected. (DS9: "Profit and Loss")

Following the outbreak of hostilities with the Dominion in late 2370, the Romulan Empire allowed the use of one of their own cloaks aboard the USS Defiant, although this was originally limited to usage within the Gamma Quadrant. Captain Benjamin Sisko chose to ignore this limitation on occasion. In order to ensure that the cloak was used correctly, Subcommander T'Rul was assigned to the Defiant initially, during the ship's first mission with the cloak. In exchange, Starfleet had to provide all the intelligence it received on the Dominion. (DS9: "The Search, Part I & Part II", "Visionary")

After the Cardassians joined the Dominion in 2373, and flushed the Klingons and Maquis out of their territory, the Klingon High Council decided to aid the Maquis in their fight against Cardassia. They provided the Maquis with thirty class-4 cloaking devices with the Klingon's understanding that they were to be used on Maquis ships. (DS9: "Blaze of Glory")

Miles O'Brien, Jadzia Dax and Rom also employed cloaking technology to hide the minefield blocking the Bajoran wormhole. (DS9: "Call to Arms")

Although quite heavy, according to Rom, Klingon cloaking devices weight less than Romulan cloaking devices. (DS9: "The Emperor's New Cloak")

Mechanics of a cloak


Penetrating the cloak

Ever since the original encounter with the cloaking device, there has been an ongoing technological race between the galactic powers; as organizations like the Federation try to develop new ways of penetrating the cloak, those who use the cloak continually devise ways to render it impenetrable.

Quantum beacon deployed

The first method of penetrating a cloak was developed in 2152, when Daniels provided Enterprise with 31st century quantum beacons so they could locate a Suliban stealth-cruiser. These devices also proved effective against some Romulan cloaking devices. (ENT: "Shockwave, Part I", ENT: "Minefield")

The cloak used by the Romulan bird-of-prey that crossed the Neutral Zone in 2266 was less than perfect, allowing a starship to pick up a blip on its tracking sensors. This blip was not accurate enough for targeting of weapons and only appeared when the vessel moved, but it was enough to help the Enterprise locate the enemy vessel. By 2268, advances in Romulan technology had removed the problem, forcing Starfleet to steal a model of the new cloak. (TOS: "Balance of Terror", TOS: "The Enterprise Incident")

Versions of the cloak used by the Klingons in the late 23rd century also had their small flaws. Small energy distortions were detectable prior to decloaking, and in 2293, the Enterprise-A developed a method of using a torpedo to track the plasma exhaust of a cloaked ship. (Star Trek III: The Search for Spock, Star Trek VI: The Undiscovered Country)

In the 24th century, the Federation protected its borders from cloaked Romulan incursion by a gravitic sensor net. In 2368, Geordi La Forge developed a technique called the tachyon detection grid that used tachyon beams transmitted between different points to expose cloaked objects. Soon, this had been implemented on the Federation's border outposts as well as in Klingon space. (TNG: "Redemption, Part II", "Face of the Enemy"; DS9: "Apocalypse Rising")

What is not commonly known, is that cloaked ships radiate a slight subspace variance at warp speeds. These variances are typically eliminated once the vessel drops out of warp. (DS9: "The Search, Part I") If a cloaked ship exceeds it's maximum speed by pushing it maximum power output, it will not be able to fully cloak, and will appear on navigational sensors as a sensor echo. (TNG: "Tin Man")

Using modified cloaks, a combined fleet of Romulan and Cardassian warships attempted to conduct a sneak attack on Founders' homeworld in 2371. They determined that as long as their fleet travelled under the speed of warp 6 their warp signatures would remain undetected, even while under cloak. This modification, however, did not prevent the fleet from being detected by the sensors aboard Deep Space 9. In this case, the cloaked fleet appeared as high concentrations of tetryon particles. (DS9: "The Die is Cast")

The Dominion, as well as the Cardassians, also possessed many methods of breaking through cloaking fields, including a long-range tachyon scanner and an antiproton beam. (DS9: "The Search, Part I", "Once More Unto the Breach") However, these methods were not always effective as Thomas Riker was able to partially counteract the antiproton beam scanning method by adjusting the cloak's resonance frequency. (DS9: "Defiant")

Improvements in cloaking technology

Firing when cloaked

Due to the enormous amount of power required to generate a cloaking field, there is by and large not enough power available to also power the weapons and shields. However, there have been several times when advances in cloaking technology have rendered this untrue.

The mirror universe ISS Enterprise (NX-01) appears able to fire weapons while cloaked using a Suliban cloaking device. (ENT: In a Mirror, Darkly)


IKS Kronos One, firing while cloaked

For example, in 2293, the Klingons developed a prototype bird-of-prey capable of firing when cloaked. This ship, commaned by General Chang was used to secretly attack the IKS Kronos One in such a way that it appeared the USS Enterprise-A was responsible, implicating Enterprise commanding officer James T. Kirk in an attempted assassination of Chancellor Gorkon. Fortunately for galactic peace, the Enterprise-A was able to deduce the existence of Chang's ship and devise a way to penetrate its cloak by tracking its plasma exhaust with new sensors for analyzing gaseous anomalies. The prototype ship was destroyed by the Enterprise-A and the Excelsior over Khitomer. (Star Trek VI: The Undiscovered Country)

Another advanced cloak was encountered in 2379. The Reman warbird Scimitar employed a new type of cloaking device that allowed the ship to fire weapons and use shields while cloaked. Not only this, but the device didn't give off any tachyon emissions or residual antiprotons, making the Scimitar completely undetectable while cloaked. The effectiveness of this technology was demonstrated at the Battle of the Bassen Rift, where the Scimitar engaged the USS Enterprise-E, the IRW Valdore and another warbird, and was able to destroy one of the warbirds and cripple the other without suffering any significant damage. Only through repeated blind targeting and barrages of phasers and torpedoes was the Enterprise-E able to disable the Scimitar's cloak. (Star Trek: Nemesis)

The interphase cloak

Interphase cloaking device

The Treaty of Algeron did not stop Starfleet Intelligence from secretly and illegally developing the interphase cloaking device, a device which not only rendered a starship invisible, but also allowed it to pass through solid matter unimpeded. The device was lost in 2358 when the testbed vessel, the USS Pegasus was destroyed in a mutiny by members of the crew concerned about the legality of the test. In 2370, the existence of the illegal device was made public to the Romulans. (TNG: "The Pegasus")

In 2368 the Romulans also unsuccessfully experimented with phased cloaking technology, developing a prototype. The USS Enterprise-D had received a distress signal from the testbed vessel, and Captain Jean-Luc Picard ordered an away team sent over to assist. During the mission, due to a malfunction in the device, Ensign Ro Laren and Lieutenant Commander Geordi La Forge were phase-cloaked during beam-out, and rematerialized on different parts of the Enterprise. After several attempts to bring them back, the crew gave up, believing them dead. Soon, Ro and La Forge encountered a similarly phase-cloaked Romulan officer that had followed them to the Enterprise in an attempt to keep the new cloaking device a secret. They fought off the Romulan, who was trying to kill them, and threw him through a bulkhead and out of the Enterprise completely. Eventually, Ro and La Forge succeeded in revealing what had happened to them to the crew, and Lieutenant Commander Data managed to reverse the effects of the cloak, bringing them back into phase. (TNG: "The Next Phase")

Ships utilizing cloaking devices


Individual ships


Background Information

There has been some controversy over the appearance of the cloaking device in Star Trek: Enterprise. TOS: "Balance of Terror" makes it reasonably clear that this is the first time such a device has been encountered, and early Enterprise episodes skirted very close to violating this by referring to the invisibility technology seen in ENT: "Broken Bow" and "Unexpected" as stealth technology; presumably this was intended to be a primitve precursor to cloaking utilizing some method other than the selective bending of light.

Unfortunately, the episode "Shockwave, Part I" featured several explicit references to the Suliban stealth technology as cloaking. "Minefield" further complicated the problem by showing the Romulans had cloaks back in the 22nd century, making some possible justifications no longer workable. Unfortunately, there is no obvious way to reconcile the discrepancies, except to force an interpretation of Spock's words ("Invisibility is theoretically possible, Captain-- selectively bending light. But the power cost is enormous. They may have solved that.") to mean that the Federation thought invisiblity was impossible because all previous forms of cloaking had been penetrated.

An alternative theory is that history as presented in Enterprise has been distorted by the Temporal Cold War. This can certainly explain the early encountering of Suliban cloaking technology. As for the Romulans it is possible that they have been given cloaks earlier than originally by agents from the future.