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ECMs (acronym for Electronic countermeasures) are any sort of electrical or electronic device designed entirely to confuse enemy detection systems. They may be used both offensively or defensively in any method to deny targeting information to an enemy. The system may make it seem that there are hundreds of separate targets, or make the real target seem to disappear or move about randomly.
The Colonial Raptor is equipped with a range of ECM systems including:
These systems fall under the purview of the ECO, but can also be activated by the pilot.
The Cylons use two forms of ECM during the Cylon attack.
The first form involves simple jamming of Colonial wireless channels during the attack. This forces any Colonial vessel to escape from jamming range or use Communication drones to transmit outside of jamming range.
The second form involves the transmission of false ship echoes to fool Colonial DRADIS scans. It takes Helo, the ECO aboard Raptor 478, several precious minutes attempting to eliminate the ghosts from the actual craft as they accompany a squadron of Viper Mark VII fighters engaging a group of Cylon Raiders (Miniseries).
While not truly a use use ECMs, which tries to overcome existing forms of detection and attack in the heat of battle, an electronic and devastating attack is made by Cylon Raiders when they transmitt a computer program to all Colonial vessels within range. This virus uses a backdoor installed into the Command Navigation Program used aboard Colonial ships to disable their integrated systems and leave them vulnerable to attack (Miniseries). Technically, this is more akin to sabotage since Cylon agents were used prior to the attack to change the CNP.