Jathaa sunglider

The Jathaa Sungliders were large, black, saucer-shaped craft employed by the Jathaa when visiting Earth. They moved via a smaller rotating platform of some sort underneath, and contained powerful weapon systems, utilising five energy beams that converge into one powerful beam capable of disintegrating a Sycorax asteroid ship into ash. (TV: The Christmas Invasion)

In 1997, the Torchwood Institute shot down one of these crafts over the North Sea, and by 2006 they had managed to reverse-engineer the weapons system. At Christmas of that year, they were ordered by prime minister Harriet Jones to use the weapon against the Sycorax spaceship that threatened Earth at the time. (TV: Army of Ghosts, The Christmas Invasion)

When the Cardiff rift fractured, mixing space and time periods, Jathaa ships appeared and hovered over the Taj Mahal. (TV: End of Days)

Behind the scenes

 * The Jathaa Sunglider's weapons system is similar to the Death Star's superlaser from Star Wars, which disintegrated the planet Alderaan into ash and meteors.
 * The technology of the weapon systems might have been incorporated into the UNIT ship Valiant later, as the beam that was seen shot from it in The Poison Sky looks very similar.