Engineering ship

From Gineipaedia, the Legend of Galactic Heroes wiki

Imperial Engineering Ships were large, specialized vessels dedicated to various engineering tasks--construction, repair work, etc. Lightly armored and completely unarmed, these ships were primarily used in non-combat roles, but began to see action in the later stages of the FPA-Imperial War and later, as Imperial commanders of the time became more willing to use unconventional tactics.

Engineering vessels were instrumental in Siegfried Kircheis' defeat of the Kastrop Rebellion in Imperial Year 487.