Yes, indeed instrument approaches are used to get aboard Navy ships at-sea. TACANs are installed aboard almost every ship with an aviation capability. This capability may only consist of a VERTREP spot for helicopters to drop their sling loads.
Carriers have TACAN approaches that usually incorporate a marshalling stack off a DME arc. ACLS (Automatic Carrier Landing System) uses radar and a data link to provide vertical/lateral guidance to the deck. The ACLS can also be used to "hand-fly" using a display that looks similiar to an ILS, but projected on the HUD. Finally, a CCA (Carrier controlled Approach) can be used which is very similar to a PAR/GCA. So, lots of ways to make it aboard for mid-rats!
Regards,
ex-Navy Rotorhead