Thunderbird 4

Thunderbird 4 was the submarine owned and operated by International Rescue. It was piloted by Gordon Tracy.

As Thunderbird 4 was built for marine travel, it could not traverse land on its own and usually had to be carried to the danger zone in Pod 4 of Thunderbird 2, piloted by Virgil Tracy. (TV: The Man from MI.5, COMIC: Solar Danger) Thunderbird 4 had a "paralyser" which shot out from the front of the craft and latched onto its target. After its target was successfully paralysed, Gordon could then operate a drill and a tranquiliser from great distances. The craft also had a soundscan which could be used to locate other boats or vessels. (TV: The Man from MI.5) After a new anti-acid skin was installed, Thunderbird 4 coped well in the sulphur lakes of Venus and, (COMIC: Solar Danger) with the specially-processed cahelium plus metal of its hull, was reportedly strong enough to support the entire World Aquanaut Security Patrol fleet. (PROSE: TB4 Trapped Under Liner)

History
In an account dated to January 1965, Gordon used Thunderbird 4 to help recover the plans to a nuclear device which had been stolen by a gang led by Carl from MI5. First using the soundscan to locate their escape craft, hidden at the bottom of the ocean, he used the paralyser and drill to successfully penetrate their submarine in less than four minutes. Gordon then activated the tranquiliser which quickly forced the three men aboard into unconsciousness and boarded the craft to steal back the plans. (TV: The Man from MI.5)

With a new skin installed to Thunderbird 4, Gordon accompanied Virgil to Venus in order to rescue the other members of International Rescue who had become stranded on the planet. Gordon went down to the bottom of the lake in TB 4 to secure the cables necessary to retrieve Thunderbird 3 but soon found himself swarmed by small lake-monsters. Gordon and his ship were pictured in a report dated 26 November, which detailed his plight and stated that even a minute's delay could result in his doom. (PROSE: TB 4 Trapped!) He was correctly advised by Brains to raise the hull temperature of the ship and discard its atomic waste as the creatures liked neither heat nor radiation. He also nudged Thunderbird 3 clear of the weeds using TB 4 which allowed Thunderbird 2 to lift it from the lake. They returned to Tracy Island two days later after various repairs had been made. (COMIC: Solar Danger)

At one point soon after the polar ship Shackleton ran into trouble, the captain reported that there was not yet any sign of help from the International Rescue craft Thunderbird 4. (COMIC: The Road to Conflict) On 12 August 2067, TV 21 reported that Gordon was entombed in his craft at the bottom of the Nicaraguan Canal, pinned there by the President cruise liner. This occurred soon after Gordon dived below the surface of the water to inspect the hull of the vessel which lay jammed across the canal. Top British metalurgists viewed Thunderbird 4s situation as a David and Goliath battle but TV 21s article reminded its readers of the ship's alleged strength. (PROSE: TB 4 Trapped Under Liner)

When the Fireflash Mk II was hijacked on its maiden flight in 2069, the demands of the hijackers, who were in cahoots with the Hood, were for all four Thunderbird craft plus their designer and fifty billion dollars. If these specifications were not met it was suspected they planned to deliberately explode the atomic reactor of the Fireflash. (PROSE: Stalemate!)