This is called HIFR.
Often done, for example, if the ship landing deck can not carry the weight of the helicopter or for some reason the ships landing deck is not operational for landings or if the roll/pitch is beyond limits for landing although the Danish Navy will land in some extreme sea state. HIFR is also done from ships with no landing deck.
https://www.youtube.com/watch?v=bC2XIGMI2kM