Cylon freighter (TOS)
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The Cylon freighter (or Cylon tanker) is an unarmed ship used throughout the Cylon sphere of influence to transport fuel and other goods. Cylon fuel tankers may be used to support an offensive operation, as demonstrated at the Battle of Cimtar. Cylon fuel tankers allow the fighters to deploy far in excess of the ranges they are normally capable of without basestar support. This frees the basestars to attack the colonies while the fighters disposed of the battlestars at Cimtar (Saga of a Star World).
Vipers from both Galactica and Pegagus launch a mission in an attempt to capture Cylon freighters in order to resupply the fleet. The plan is foiled when Commander Cain intentionally destroys the freighters in order to force Adama into a position where he needed to attack Gamoray (The Living Legend, Part I).