Tri-Cobalt torpedoes use three different types of explosives, Quantum filaments, Tri-Cobalt and Antimatter. Upon impact these devices are mixed in that order and produce a lethal explosion. The explosion is enough to completely disable a starship. Quad-Cobalt torpedoes are based on a similar principle. Upon impact, the microfusion initiators inside the casing fuse the cobalt with pure antihydrogen, creating a very unstable compound, which then mixes with plasma from the torpedo's engines, causing rapid total annihilation of the torpedo and a massive explosion as powerful as 250 photon torpedoes.
During the initial scare in System J-25 with the Borg one of Starfleets many projects was the Tri-Colbalt Device. It was the predecessor of the Quantum Torpedo but in effect had ten times the destructive capability. Again, this project used three of the most powerful explosives know to Starfleet, Tri-Cobalt, Antimatter and Quantum Filaments. Quantum Torpedoes use Quantum Filaments which arc out over the targets hull ripping it to shreds, however the principle with the Tri-Cobalt device differs from this. Tri-Cobalt is normally a reasonable stable compound unless it is broken down at the molecular level. In the past Starfleet had tried to use it as an explosive, but failed due to impractical methods. However with the discovery of Artificial Quantum filaments the situation changed drastically.
The design of the Tri-Cobalt device is highly unique in the Alpha Quadrant. It uses a three tear warhead. One compartment is loaded with Antimatter, one with around 200 Quantum filaments and an appropriate amount of Tri-Cobalt. Upon impact there is a number of things that happen inside the warhead.
Firstly the Quantum filaments are released into the Tri-Cobalt chamber creating a cascade reaction, mixing the Tri-cobalt into a highly volatile mixture. A millisecond later the magnetic containment field around the antimatter is released and the active Tri-Cobalt and Anti hydrogen mix together creating a lethal explosion. The weapon is capable of disabling starships with one blow, as Starfleet unfortunately found out.
Initial testing of the weapon took place just before Wolf 359. Designers were panicked and rushing the project through under Starfleets hasty gaze. USS Keel, an Excelsior class ship was the test vessel. The first few barrages in the Asteroid field in the Terran system proved to be massively successful. However in the final day of testing an accident occurred. One of the devices lodged itself in its launching tube and the warhead went critical. The resultant explosion tore the saucer section clean off the Keel and the minutes later the warp core in the drive section went critical. A total of 40 lives were lost in the accident and only weeks later Wolf 359 Occurred.
Designers eventually figured out what had gone wrong. The Tri-Cobalt device was in theory much heavier than a standard photon torpedo, and although the designers had taken this into account when modifying the launching tubes on the Keel they had not been sufficient.
After the disaster at Wolf 359 Starfleet was still interested in using the Tri-Cobalt device on Starships. Quantum Torpedos were now in development, however the sheer destructive capability of the weapon was seen as a possible defence against the Borg, who's vessels were very large targets. The designers took the launching system back to the drawing board and eventually came up with a highly safe system. From that point on Starfleet order all new ships to be fitted with this kind of launching system and a steady retrofitting of the defensive capabilities of the other ships in the fleet (Note the Lakota). The standard ship compliment is for four Tri-Cobalt devices. Any more would pose great danger to the ship. In addition ships on diplomatic or internal missions are have the warheads removed for safety reasons.
