Below you’ll find more-or-less a guide on all torpedo ordinance and their availability. All information is from official sources, and assumptions are cleared stated as such. After review by the ASDB Team, it may eventually find its way into the "Articles" section of the ASDB Website.


Photon Torpedoes:

Matter/antimatter annihilation weapon used by Starfleet that contains deuterium and magnetically constrained antideuterium tanks which are simultaneously released at the point of detonation, mutually annihilating each other and producing a high-energy explosion. These devices are present on almost all Federation starships and are quite well known in terms of their capabilities.


Photon Torpedo Statistics (TNG Era) – TNG TM


3,500,000 Kilometers

Max Yield:





247.5 Kilograms


Photon Torpedo Statistics (Post-TNG Era) – DS9 TM


4,050,000 Kilometers

Current Max Explosive Yield

18.5 Isotons

Theoretical Max Yield:

25 Isotons


2.1 x 0.76 x 0.45 meters


186.7 kilograms


Between the end of Season 7 of TNG and the DS9’s Dominion War, the photon torpedo was upgraded in terms of its yield thanks to more efficient internal designs, allowing for less electronics and more fuel. This brings the standard torpedo yield to 18.5 isotons, though its been theorized that a maximum yield of 25 isotons may someday be reached (i.e. cannot currently be reached).


Galaxy-class starships are capable of simultaneously loading ten torpedoes at once in a single tube, allowing for quick launch of all the devices. Standard torpedo launchers, as stated in the DS9 TM, are capable of simultaneously fueling reactants into four torpedoes at a time and can dispatch volleys of six torpedoes within 2.3 seconds, with reload times as short as 15.3 seconds. This could explain why torpedoes are frequently fired in spreads of three or four at a time as seen during the Dominion War, “First Contact” and in “Nemesis.” Unfortunately, it is never made clear which ships carry a “standard” torpedo launcher.


Quantum Torpedoes:

A newer torpedo device that uses a traditional 21.8 isoton matter/antimatter reaction to jump-start an energetic local release of a zero point energy field, which is more effective at penetrating deflector shields with a theoretical maximum yield of 52.3 isotons. Unlike the photon torpedo, quantums are manufactured at a limited number of hidden facilities within the Federation. Because of the nature of various exotic materials, many of the components cannot be replicated and thus cannot be manufactured locally aboard starships. According to the DS9 TM, half of all manufactured quantum torpedoes are allocated to DS9 and the Defiant. It also states that vessels handling quantum torpedoes must observe special handling and loading precautions, including antigravs, tele-robotic servicing and protective buffer fields.


Three different starship classes have been observed to make use of quantums: Defiant-class, Sovereign-class, and the Excelsior-class U.S.S. Lakota. The Lakota is an exception to the rule, since information in that episode specifies the ship was refit with new hardware to take part in Admiral Leyton's coup on Earth.


The Sovereign-class U.S.S. Enterprise NCC-1701-E has been seen making use of quantum torpedoes, specifically from a forward launcher on the ventral side of the saucer near the Captain's Yacht docking port in "First Contact" and "Nemesis," though the vessel also fires photon torpedoes from various other launchers in "Insurrection" and "Nemesis."


Various Defiant-class starships have been seen using only quantum torpedoes in numerous episodes, though the DS9 TM states the vessel's launchers can handle both quantum and photon torpedoes depending on what is available.


Given the powerful nature of this type of weapon, it's surprising that we didn't see other starship classes making use of it during the Dominion War, specifically in episodes such as "Sacrifice of Angels" and "What You Leave Behind." In both instances, it was well known that all ships involved would be taking part in massive battles, yet they were still not equipped. It can be inferred that either other starship classes lack some specific hardware in their torpedo launching systems that prevent them from using quantum torpedoes (such as the previously mentioned protective buffer fields), or that Starfleet keeps a tight leash on its supply. The DS9 TM specifically states that much higher security restrictions are in place for the quantum torpedoes, and that distribution is rationed.


That said, only ST:ACTD's Defiant and Sovereign-class starships carry quantum torpedoes as part of their standard loadout. Unless we change our stance on the differences involved in the physical launching of torpedoes, only ships under special circumstances can have a few allocated for mission-specific purposes. We're not talking "Oh, it'd be easier to destroy this station with quantum torpedoes," it's more like "we can't destroy this station without quantum torpedoes." If Starfleet is unwilling to let other starship classes make use of them during an all-out war, then the circumstances warranting usage should be greater then that, and any unused torpedoes from said mission-specific applications would be returned afterward in accordance with protocol.


Tricobalt Torpedoes:

Information on this device is derived primarily from two episodes, Voyager "Caretaker" and "The Voyager Conspiracy." The former gave us little information, suggesting it was more like a traditional torpedo explosive that was somehow more effective at destroying things, in this case the Caretaker Array. The latter episode allows us to infer much more information as Seven investigates the incident surrounding the first episode. The purpose of using the two tricobalt explosives was to ensure that little of the Array would be left intact for the Kazon to make use of, and sc+ans afterward show little more then metal vapor of some unknown alloy. The blast managed to cause a tear in subspace, where we learn a tetryon reactor was pushed.


Unlike photon and quantum torpedoes whose explosive potential is measured in isotons (much like 20th Century atomic weapons being measured in the equivalent amount of TNT in tons needed to cause such an explosion) the tricobalt torpedoes in this episode were calibrated to a yield of 20,000 terracochranes, which is said to be more then enough for the Caretaker array and caused a subspace tear to form. Cochranes are the unit used to measure subspace field stress, such as in warp fields.


Therefore, we can assume that the purpose of using tricobalt devices is to distort space around an object by causing subspace instability, and that fields around 20,000 teracochranes can actually tear the fabric between normal space and subspace for short periods of time. The subspace field needed to propel a ship at Warp 9 is around 1000 cochranes, so the distortion of space as a result of these devices is enormous in comparison, and could easily destroy objects through means of a shearing force. It's comparable in some respects to an earthquake, and how the shearing forces can crumble a building that's normally stable.


It's also noteworthy to point out that tri-cobalt devices would be less effective against shielded objects, since shields make use of a local distortion in space that's gravity-based.


Seven also states throughout the course of the episode that tri-cobalt devices are not common ordinance aboard Starfleet vessels, and it was never clearly stated why Voyager had two such devices in their compliment. This allows us to safely say that Starfleet ships and ST:ACTD ships in general do not carry tricobalt on a normal basis, and that there should be a good reason to have them aboard. It seems to further suggest that these devices cannot be manufactured onboard a starship.


Transphasic Torpedoes:

Featured in Voyager "Endgame," this weapon was brought from the future by Janeway and could easily destroy a Borg Cube with just one direct hit. This would make the transphasic torpedo more powerful then even the energy beams combined from several Species 8472 bioships as seen in Voyager "Scorpion." The name “transphasic” implies that the warhead is somehow phased, either temporally or dimensionally, from normal space, effectively allowing the torpedo to pass through a ship’s shields with little or no resistance. Because they were launched from Voyager, it can be assumed that they’re approximately the same size as a standard photon torpedo, though we know nothing on how the devices must be handled.


Other then being quite powerful, little is known about the workings of this weapon. The absence of future technology such as transphasic shields and “Batmobile” deployable ablative armor in the recent movie "Nemesis" reinforces the notion that this technology is being kept secret, and far from public eyes due in no small part because of the Temporal Prime Directive.


To that end, under no circumstances will these weapons be featured in ST:ACTD missions taking place in the normal timeline. It's understandable that missions taking place in the far future might showcase these technologies, however. Knowledge of these devices is classified and not common knowledge... even for Starfleet Captains. Aside from seeing the U.S.S. Voyager covered in "Batmobile" ablative armor upon exiting the Borg Sphere, ships making up the small fleet that greeted it never got a chance to see her weapons in action, and it is conceivable that members of Voyager's crew would be told to withhold such information from other persons. That said, you shouldn't even know about the existence of transphasic torpedoes… much less any other futuristic technology Voyager brought back.



As it is both ST:ACTD and the ASDB's goal to adhere to canon as much as possible, we encourage all SMs to abide by these guidelines to help make a more realistic gaming experience. It is important that you make use of the unique characteristics that your ship's starship class already has, rather then try to make it into something it is not. Intrepids sport fast top speeds, Ambassadors are large in size and have practically the same benefits as the Galaxy, Novas have great sensors, while Defiants boast great weapons but poor recreational and science facilities. Ships are not made "cooler" by carrying something that is restricted or rationed... it only makes them more out of place in the Star Trek universe, and less realistic.



  1. Tricobalt Torpedoes – Jason Sharp
  2. Star Trek: The Next Generation Technical Manual - Rick Sternbach and Michael Okuda
  3. Star Trek: Deep Space Nine Technical Manual - Herman Zimmerman, Rick Sternbach and Doug Drexler
  4. Star Trek: The Magazine
  5. Star Trek: First Contact
  6. Star Trek: Insurrection
  7. Star Trek: Nemesis
  8. Star Trek: Voyager “The Voyager Conspiracy”
  9. Star Trek: Voyager “Caretaker, Pt 2”


Created by Robert Siwiak.

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