The Collaborative International Dictionary of English v.0.48:

Unship \Un*ship"\, v. t. [1st pref. un- + ship.]
   [1913 Webster]
   1. To take out of a ship or vessel; as, to unship goods.
      [1913 Webster]

   2. (Naut.) To remove or detach, as any part or implement,
      from its proper position or connection when in use; as, to
      unship an oar; to unship capstan bars; to unship the
      tiller.
      [1913 Webster]