Apparently, they're planning to use a dirigible to lift an important Precursor artifact from the muck!”— Samos Hagai, The Precursor Legacy
The dirigible, or zeppelin, is an airship used by the Lurkers during The Precursor Legacy. The dirigible was an important piece in Gol and Maia Acheron's plan to collect Precursor artifacts to build their own Precursor robot. It was stationed over Boggy Swamp where it was tethered to an arm of a Precursor robot as well as four large boulders, Samos Hagai requested Jak to destroy the boulders in the "Break the tethers to the zeppelin" missions. After they were destroyed the tether to the robot broke, causing it to sink in the mud, not to mention the dirigible itself drifted away in the wind.
It is shaped like an airship, with a balloon above it and around ten oar like objects with sails on. It also has spikes protruding from its body. It is very similar in shape to what the balloon lurkers on Misty Island use for transport, only super-scaled, it is in fact large enough that it is visible from Samos' hut. It is probable it was also in the area to accommodate or transport the large numbers of Lurker troops that Jak fights in the area.