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A Heavy Raider is a Cylon dual purpose attack and transport spacecraft, analogous to the Colonial's Raptor vehicle. It is nicknamed a "turkey" by the surviving Colonial Fleet's military units (TRS: "Maelstrom").
The Heavy Raider shares many design similarities with the rest of the Cylon fleet, featuring an autonomous bio-mechanical design. However, this craft is also easily piloted by Centurions or Humanoid Cylons if needed. The Heavy Raider has no windows, and any Cylon piloting the craft must rely on telemetry delivered to a Datastream inside the craft for operation (TRS: "The Farm", "Deadlock").
Heavy Raiders typically carries two tri-barreled automatic cannons capable of high rates of fire. These are further augmented with ship-to-ship missiles, which can be easily connected to the Raider's DRADIS dish and converted into anti-aircraft batteries for use on a planetary surface (TRS: "Fragged").
The Heavy Raider was developed sometime during the forty year Cylon exile from Colonial contact, and were used in combat during the Fall of the Twelve Colonies. Heavy Raiders delivered Centurions to the surface of Caprica and likely other Colonies as the start of the ground invasion (TRS: "The Plan"). After the Fall, they continued to serve as troop transports for Centurions boarding the battlestars Pegasus and Galactica (TRS: "Scattered", "Fragged", "Razor") and entering battle on the Algae planet (TRS: "The Eye of Jupiter", "Rapture"). The Cylons deployed one for every ten or so autonomous Raiders when attacking space-based targets (TRS: "Resurrection Ship, Part I", "Flight of the Phoenix"). They were also used to suppress human resistance fighters on the ground during the Cylon occupation of New Caprica (TRS: "Occupation").
Humans and their allies were able to take advantage of Heavy Raiders. With the help of a rogue Number Eight Cylon, the Caprica Resistance stole a Heavy Raider to rescue Kara Thrace from a Cylon farm, evacuate the resistance fighters to their base, and allow Thrace, the Eight, and Karl Agathon to jump to Kobol and reunite with Laura Roslin's faction (TRS: "The Farm". Home, Part I"). With the help of the same Eight, Thrace was later able to use the navigational computer of the Heavy Raider to jump a fleet of Raptors to Caprica to rescue the remaining Caprica Resistance members (TRS: "Lay Down Your Burdens, Part I," Lay Down Your Burdens, Part II"). Heavy Raiders tow Vipers into battle in order to catch Cavil's faction off-guard during the Battle of the Resurrection Hub (TRS: "The Hub"). Admiral William Adama reluctantly authorizes a Heavy Raider reconnaissance mission to the Colony as part of an attempt to rescue the kidnapped Hera Agathon (TRS: "Islanded in a Stream of Stars").