The DDG-62 is a model of sublight engine, outdated by the time the Fall of the Twelve Colonies had occured. The engines are apparently meant for small, one-man craft, and provide ample acceleration that seems to match that of a Viper Mark II.
During the construction of the Blackbird, a prototype craft devised by Galen Tyrol and constructed by crew of battlestar Galactica, Colonel Saul Tigh offered Tyrol a pair of these engines that were taking up space in the Baah Pakal's cargo hold. (Flight of the Phoenix)
The engines were designed by aeronautical engineer Peter Laird, who said that they were mostly phased out of use 10 years ago. (Pegasus)
Notes
DDG-62 is also the real-word designation of the US Navy Arleigh Burke class destroyer USS Fitzgerald. DDG is the Navy hull classification for a guided missile destroyer.
The engines' name is an homage to that very ship. The show's science advisor Kevin R. Grazier organized a tour of the vessel for the writing staff. Ultimately only Bradley Thompson and his wife attended, but he later included the reference into the episodes. Source: BSG Tech Blog #6