A cloaking device uses a combination of gravitational lensing and energy screen generation to render an object invisible (to the eye and most sensor systems). The gravitational lensing creates a distorted image of an object as light reflecting from the object is bent by gravity. In the case of cloaking devices, the light is focused so that the object's index of refraction(phase velocity of radiation in a vacuum divided by the phase velocity of the same type of radiation in a specified medium) matches that of it's surroundings,
making the object transparent. To fully cloak a ship you must do the following things:

     - Balance the emissions from the ship's warp nacelles
     - Dissipate all electromagnetic radiation emanating from the ship
     - Hide or distort the ship's gravitational field
     - Distort space so that all EM and energy emissions
       are directed around the ship through subspace FTL.

Balancing Emissions From The Warp Nacelles        Back to Top 

Off-axis warp field controllers are used to balance the emissions from the warp drive. This is necessary because the power source must be operating in phase with the cloaking device to ensure that no detectable emissions escape. Off-axis warp field controllers are also use don warp capable ships
without cloaking devices, as they also increase the efficiency of the warp drive.
If any of these controllers are misaligned or damaged then the warp drive would produce a polarised magnetic distortion which would be easily detected by the sensors of another starship. If the ship was travelling at warp, the fact that the ship is moving so quickly makes it difficult to pin-point the location of a ship, even one of it's warp field controllers was misaligned.

Dissipating All E.M. Emissions From The Ship         Back to Top

The nullifier cores dissipate all of the electromagnetic radiation and any others energy emissions produced by the ship and it's crew. This is done by remodulating the energy signature to have the appearance of background radiation and reducing the apparent output. Providing shielding against the
entire electromagnetic spectrum is energy costly, but necessary if another ship is in close proximity. If a ship isn't within the immediate vicinity then the nullifier cores only dissipate EM frequencies detectable on long-range scanners. Cloaking systems Mk 3 to Mk 3.2 require the space craft to have a green coloration, because of problems with spurious thermal emissions trapped inside the cloaking field. The nullifier cores also mask the ship's gravitational field. Cloaking generator coils use a coherent graviton emission to distort space so that incident electromagnetic radiation and other forms of energy are directed around the ship through subspace at velocities faster than light, making the appearance that the light or energy never left it's original course. One of the main parts of a cloaking generator coil is a graviton polarity source generator. Graviton polarity source generators create a highly focused spatial
distortion which directs the course of the energy and light. The graviton polarity sources in each generator feed into subspace field distortion amplifiers that are phase-synchronised with each other by a network of small conduits that allow field bleed for gravitational stability between the graviton
polarity sources. These conduits are equipped with tetryon compositors, to prevent a build-up of tetryons in the conduits, which would decrease the operating efficiency and eventually significantly damage the subspace field distortion amplifiers. The flux energy output is directed and focused by a
series of subspace field generator coils, according to the energy dispersal pattern. The energy dispersal pattern, or the energy transformational matrix, is the way in which the energy and light is directed around the ship. The actual subspace field generator coils are similar to warp field coils, but they create a multi-layered field in the space around the ship, not also within it. The propulsive, asymmetrical, peristaltic field distortion propels the energy faster than light. This compensates for the extra distance that the energy has to travel around the ship before returning to it's original course, and any redshift
or blueshift caused by the Doppler effect, or a gravitational field. The cloaking generator coils are controlled by special purpose, or dedicated, computers designed to perform this specific task. They are extremely fast computers that contain a complex arrays of processors each designed to perform a specific function. These computers must handle huge databases, and perform complex mathematical operations in order to provide an accurate energy dispersal pattern. Input data is provided for the computers by a network of refractometers placed on the hull of the ship. The more refractometers placed on the hull of the ship, the more effective the energy dispersal pattern. The only limiting factor is the speed of the computers, which must provide a real-time energy dispersal pattern to effectively cloak the ship. These computer are completely separate from the computers that perform other ship functions, because they are limited to the specific function built into them. These computers are only required on fine tuned cloaking devices, Mk 3.2 and higher.

Magnetic constriction coils create a localised magnetic waveguide plane for the energy to pass through in subspace, which ensures proper alignment of the energy when the ship is in warp. If a ship was using the magnetic constriction coils while not in warp, an active magnetic interferometry scanner could detect the use of the coils. All of the parts of the cloaking generator coils are powered by plasma coils.
These coils must all have an identical energy frequency. This is accomplished by a plasma buffer. If there is no plasma buffer, then the cloaking generator coils could easily be disrupted, by something like an ionic pulse.

Types Of Cloaking Field                             Back to Top

There are many forms of energy dispersal patterns, some more energy efficient or more anti-detection effective than others. The energy dispersal pattern for a ship must be very carefully calculated. There are generally two classifications of energy dispersal patterns: spherical cloaking, and wavemapped cloaking.

On the spherical cloaking mode the cloak is generated at a constant distance from the centre of the graviton polarity source generators. However, as the gravitational effect is less significant, the shape of the field becomes more elliptical, i.e., less spherical. This distance is controllable up to a point, when
the power system of the ship the can no longer support a field of that size, and the cloak chaotically collapses, causing powerful gravitational waves. This setting is intended for use during warp travel, whereby the cloak surrounds the warp fields and effectively cloaks it also. The spherical cloaking mode produces a noticeable distortion of visible light with some energy dispersal patterns. This is because the field behaves as a lens, focusing light in places and diffusing it in others. This is especially noticeable as the cloak engages and disengages.

On the wavemapped cloaking mode the cloak is generated at a constant distance from the surface of the ship. It is possible to create an energy dispersal pattern, on a very well tuned vessel, less than thirteen millimeters from the hull by emitting the cloaking field from a series of conformal transmission assemblies on the hull which are connected to the cloaking generator coils. Constant computer monitoring is required at this level, and cannot be performed at warp. Wavemapped cloaking cannot be instantly engaged or disengaged, because of the complexity of the field geometry. The cloak is carefully powered down to avoid damaging the cloaking device. In an atmosphere, gas will get trapped inside the cloak if wavemapped. This will cause sound vibrating between the hull and cloaking field, making an audible noise.

Detection Systems                                 Back to Top

Subspace listening posts, gravatic sensor nets and tachyon heterodyne detection grids can be used to track cloaked ships.

Subspace listening posts are designed to listen for any subspace radio, subspace field distortions (these indicate the presence of a warp drive), any subspace compression (a possible warp drive error), or subspace shock waves small enough to be undetectable by standard sensor arrays (these indicate a spontaneous warp field collapse.) Subspace relay stations, which boost subspace radio transmissions, can be converted to subspace listening posts without much difficulty. Gravatic sensor nets are a network of detection devices that are partially effective in detecting cloaked ships. Gravatic sensor nets utilise highly
sensitive gravimetric distortion mapping scanners to map the gravitational forces throughout the area in which it would be probable that a cloaked ship would pass. If a cloaked ship's nullifier cores were not creating a complete area of null gravity around the ship, then it would be possible to observe the
changes in the space around the ship. Tachyon heterodyne detection grids are a network of active tachyon beams used to detect cloaked ships passing through the net. Tachyon heterodynes are charged tachyons having alternating currents of two different frequencies that are combined to generate a new frequency equal to the sum or difference of the two.

Disadvantages                                      Back to Top

As a cloak engages and disengages, a momentary gravitational wave forms from the graviton polarity sources, while the subspace field distortion amplifiers phase-synchronise with each other. (Gravitational waves also called gravitational radiation or spatial ripples.) A gravitational wave is a ripple in the curvature of space-time In other words, it is a propagating gravitational field, or propagating pattern of strain, travelling at the speed of light. It carries energy and can exert forces on matter in its path, producing, for instance, very small vibrations in elastic bodies. As the ripple forms, the ships inertial
damping system will attempt to respond. But because, on average, the inertial damping system lags 295 milliseconds to respond, there is a slight strain of the physical spaceframe of the craft. If the ripple is fairly limited, no considerable effect will result, but, should the ripple be large, the systems will
fail to adequately compensate and the ripple can cause a significant effect on the ship and crew. This distortion, although the relatively weak interaction between gravitational radiation and matter, can create an effect similar to that of spatial interphase, which alters the neural pathways in the brain, effectively
rendering any humanoids exposed to the spatial radiation insane, or worse. Statistically, on a Mk 3.2a cloaking device, a ripple large enough that it cannot be adequately compensated for, should occur some 0.00007854% (39,271/50,000,000,000) of the time. A build-up of tetryons in the conduits that allow field bleed between the graviton polarity sources will significantly increase the chance of a spatial ripple occurring. A neural disturbance should occur approximately 0.0000001386% of the time, with a 0.000000000341% (341/100,000,000,000,000 ) chance of complete structural failure due to
spatial ripple stress.

In addition to the production of gravitational waves, cloaking devices have several other significant disadvantages. The greatest disadvantage is the tremendous amount of energy required to maintain all of the parts of the cloaking device. If a ship had the ability to generate enough energy to maintain the cloaking device as well as defensive shields, the nullifier cores could neither mask all of the energy required to accomplish this, nor the interference created by defensive shields. In addition, the spatial distortions created by defensive shields would mean that the shield itself would have to exist within the
cloaking field, and the larger the cloaking field is, the more energy is required to generate it. These reasons completely eliminate the possibility of using defensive shields.

When a starship's cloaking device is active, several ship's systems operate under special protocols to minimise the interference of the cloaking device. If the cloaking generator coils distorted space so that all incident electromagnetic radiation and other forms of energy were directed around the ship, then the sensor systems could not gather any data. As a result, the cloaking generator coils create frequency windows to allow specific wavelengths to pass through the cloaking field at certain times. This limits the
gathering of many types of scientific and tactical data, but is adequate for most situations. Active scanners may not be used while the cloaking device is operating. Although the transporter system could be tuned to the same frequency as the cloaking device, the gravitational distortions usually prevent usage of the transporter system.

Phased energy weapons make use of the rapid nadion effect. This is very disruptive to the cloaking device's plasma coils, even with a plasma buffer, and therefore cannot be used. If a cloaked ship did use their phasers, the beam would be bent off course and hit the ship at a diametric point and angle.
In addition, the nullifier cores would attempt to dissipate the phaser beam and remodulate its energy signature to give the appearance of background emissions. The cloaking field would most likely collapse, causing powerful gravitational waves. However, it is possible for a phaser to penetrate the cloak
from the outside if it is tuned to the frequency of a window opened in the cloak for sensory input.
Warp drive operation is considerably affected by the cloaking device. The geometry of the warp field must be significantly altered because of the spatial distortions created by the cloaking device. Warp drive control software works in parallel with the cloaking generator coil's dedicated computer to minimise
the effect on both systems. The translational field interaction between the cloaking device and the warp drive is somewhat chaotic, creating potentially catastrophic effects. Such as a spontaneous field collapse of the warp field or subspace compression. This is why subspace listening posts are an efficient
way of tracking cloaked ships.

It is possible to open an interference window in a finely tuned cloak, so that a photon torpedo will pass through, as opposed to being bent off course or even crushed by the gravitational distortion. This interference window is generated by, at the moment of firing, a cloaking generator coil to operate on a different frequency than the other cloaking generator coils. This is accomplished by temporarily disconnecting the plasma coil powering the cloaking generator coil for the area where the torpedo will leave the cloaking field from the plasma buffer. The translational field interaction between the cloaking
generator coils causes a gap to open in the cloak. The calculations that are necessary to allow the ship to properly cloak after the launch of the torpedo are very complex. As a result, there is a lag in firing, the length of which depends on the speed of the cloaking generator coil's dedicated computer.
Because the navigational deflector dish radiates significant amounts of both subspace and electromagnetic radiation, it cannot be used when cloaked without an extremely powerful network of nullifier cores, which would consume a considerable amount of energy. Instead of this, a variant of the
transporter system is used. This device converts the micrometeorite particulates to energy, lets the energy be directed around the ship as with all of the other light and energy, and then converts the energy back to matter. This method is only used when a ship is in very close proximity. Otherwise the
magnetic constriction coils are tuned with the cloaking generator coils to reflect interstellar gases and micrometeoroid particulates. This method is more energy efficient than the method using a variant of the transporter system.

Molecular Phase Inversion                          Back to Top

A molecular phase inverter is a device that could alter the molecular structure of matter so it could pass through normal matter and energy at certain angles. The angles that phased matter can pass through normal matter and energy at are determined by the matter's quantum state. Theoretically, if quantum
mechanical subatomic particles were phased, they could pass through normal matter at every possible angle. In this case, there would be absolutely no source of drag or resistance. The inertia of a body could carry it on the same course at the same velocity as when it was phased until the body was dephased.

An interphase generator is a molecular phase inverter combined with a cloaking device. Matter exposed to this interphase generator would partially exist on a parallel spatial plane (similar to that of subspace) and would therefore be undetectable to any known sensing device. This is similar to coplanar spatial interphase, a time-space phenomenon in which two or more dimensions overlap and connect. Matter so cloaked can pass through normal matter, with the same limitations previously discussed. When phased matter passes through normal matter chroniton particles are formed. A modified anyon emitter can clear chroniton particles and when set to a sufficient strength, dephase phased matter.

Cloaking Device Classification                       Back to Top

Mk 1 Cloak: Original usage, early Warbirds only. Used electromagnetic radiation shielding quite effectively to cloak only visible and near-visible radiation. Can instantaneously cloak and decloak, but required large amounts of power.

Mk 2 Cloak: A major improvement on the Mk 1, this device cloaked all electromagnetic radiation, except high energy Gamma rays. Can instantaneously cloak and decloak, but was remarkably inefficient. Craft:
Romulan Scouts and Warbirds, also Klingon D-7 Cruisers, and later the joint Romulan/Klingon scout and Bird Of Prey.

Mk 3.0 Cloak: The first gravity distorting cloak. The early prototype craft had problems with energetic effects occurring inside the cloak as a result of trapped spurious thermal emissions within the cloaking field. This was overcome by giving the craft a green coloration. This tuned the thermal energy to a frequency where it could leak very slowly through the cloak without revealing the ships presence, still common practice on most cloaked vessels. This early Mk 3 had only the spherical field setting and could not be effectively wavemapped. It could not instantly cloak and decloak, but saw
much use on most Romulan craft and the Bird Of Prey.

Mk 3.1 Cloak: This improved device featured instantaneous propagation of the spherical cloak, and first saw use of the wavemapped cloak. It is reported to have been used as above and as an upgraded cloak for D-7 Cruisers. A green coloration was still necessary.

Mk 3.2 Cloak: This version saw the creation of the fine tuned cloak, using the special dedicated computers. This device was perhaps first created by the Klingons, but required large power reserves. The Romulans later reworked the idea into a more efficient form (officially designated the Mark 3.2a). The old cloak is still in active service on older Klingon craft.

Mk 3.2a Cloak: Romulan reworking of the 3.2. No special coloration of the craft is necessary, although the nullifier cores require less energy when the ship has a green colour. The cloak is still extensively used by Romulans and Klingons alike.

Mk 3.3 Cloak: This latest version allowed powering down of all non-finely tuned cloaks instantly. It is only fitted, as far as is known, to Romulan Warbirds. Klingons claim to still use the 3.2a.

Experimental Mk 4 Cloak: There is an experimental cloaking device which utilises a highly-wavemapped, adaptive, asymmetrical dispersion pattern. This cloaking device's cloaking generator coils are equipped with field actuators that change the dispersion pattern, to be most efficient in any interstellar
condition, considering many variables, such as gas density, electric and magnetic fields, and fluctuations in the subspace domain. These field actuators compensate for any of these variables or active scans if the vicinity of the cloaked ship is being probed. There is no danger of a spatial ripple occurring. This would render a ship undetectable, except with a tachyon heterodyne detection grids, which, if powerful enough, could detect a ship that was cloaked in this manner.

History                                             Back to Top

On Stardate 1709.1 the Bonhomme Ri left Romulan Space. Suddenly, it vanished from the sensors, reappeared directly in front of the outpost and fired what later came to be called a "plasma torpedo". The torpedo obliterated the outpost's deflector screens, nearly destroying it. A second shot finished
the intruder's job. Then the ship simply disappeared from view. That was the first encounter with the Romulans after almost a century since the battle of Cheron. The vessel that destroyed S-4023 (and also S-4024 and S-4025) was a Romulan P-1A Bird of Prey with a first generation cloaking device.
Later, a third generation cloaking device has been obtained by the U.S.S. Enterprise in an espionage mission. The Klingons gained the technology from their alliance with the Romulans in exchange for their D-6 Raxor and D-7 Klolode battle cruisers. Thus the three major powers in this part of the galaxy came to posses what proved to be one of the most formidable weapons ever. Starfleet, which used the cloaking device on its vessels in the late 2200's and early 2300's, has decided that the peaceful (mostly) mission definition of the Explorer type of starships precludes its use. Further- more, the overall shape
and hull materials used in the Galaxy, Ambassador, and Oberth class starships would interfere with the cloaking device. Although it is still possible to cloak them, the energy necessary increases beyond reasonable limit. Today, only specialised scouting, stealth, and battle ships use cloaking devices. The Klingon Empire has used the cloaking technology ever since their technology exchange with the Romulans in 2263, and continues to do so. Nearly all of its Bird of Prey type ships are equipped with it as are the D- 6, D-7, D-8 (K'T'Inga), and the new K'Vort class battle cruisers. The Romulan Empire naturally still uses the cloaking device. Although much about them is now unknown due to the fifty-year contact breach after the Tomad incident, it is certain that their newest vessels, the D'Deridex class
warbirds, are equipped with a new generation of cloaking devices which have so far defied all Federation attempts at detection without the use of tachyons. The events surrounding the Khitomer conference, classified until recently, have brought to attention the fact that one of the main disadvantages of the
cloaking device, the inability to fire a photon torpedo, has been nullified by the renegade Klingon vessel Dakronh. Although it was destroyed, and it's schematics have not survived, it appears that the cloaking device would be useless today due to the vast improvement of sensor devices used by Starfleet. The vessel was designed reduce the cloaking power shortly before firing, just enough to fire a specially designed high-velocity photon torpedo thorough it. However, this resulted in a momentary emission of radiation from the ship and the leak of impulse engine products (plasma) through the cloak.
The vessel was destroyed by homing a photon torpedo on those plasma traces. The momentary radiation burst from the ship as the cloaking power was reduced was too small to be detectable by the instruments of that era, but would be sufficient to pinpoint the ship's location today.