 The Australian Sea Kings had similar avionics to that of the Sea King HAS.1 , with the same ARI <unk> search radar in a dorsal radome , but had American Bendix AN / ASQ @-@ 13A dipping sonar instead of the Plessey sonar of the Royal Navy Sea Kings . They also had more powerful engines giving improved high temperature hover performance . Australia 's Sea Kings were flown by 817 Squadron RAN from HMAS Melbourne until the carrier was retired from service , without replacement . As the Sea King was too large to operate from the Adelaide @-@ class frigates , 817 Squadron was then forced to operate from land bases , in both ASW and utility roles , with the Sea King relinquishing the anti @-@ submarine mission in 1990 . 
