Alta Class Mineweepers and Oksoy Class Minehunters LOA 181′ / 55.2 m TDISP 375 tons (6 active, 3 of each class, service since 1994, Alta Class Orkla M-353 destroyed by fire 2002). Virtually identical catamaran hulled ships with different roles, based on equipment on the rear deck.
Alta Class Rauma M-352 River Clyde, 2006 Credit: BigStuart at English Wikipedia / CC BY-SAKNM Hinnøy M-343, Oksøy-class mine hunter, visiting River Mersey, Liverpool, ca. 2013. Credit: Harrias / CC BY-SABased on the above photos, these appear to be Oksøy class. Note the smaller step-down to the stern counter.Based on the above photos, the upper vessel appears to be Alta class. Note the larger area at the stern.
Sauda Class minesweepers and mine hunter LOA 144′ / 43.9 m TDISP 330 tons (10, 1 preserved)
HNoMS Alta M-314 (1966-1996) Museum ship of the Royal Norwegian Navy Museum in Oslo Harbour
KNM Alta M-314, museum ship, entering Horten Harbour, ca. 2013 Credit: Ulflarsen / CC BY-SA
The Searchers 