Sikorsky S-61/Sea King questions?

Were waterborne landing regularly performed by any S-61/Sea King military or civillian operators? The S-61 design was built to conduct waterborne landings up to Sea State 3. The reason I’m asking is because I was recently having a chat with a friend who served in an S-61 squadron and he mentioned that waterborne landings were very unpopular with crews. One reason was because of the gush of water created by the rotor down wash which effected the visibility of the pilot during lift off. Another reason was because upon returning to base the whole aircraft had to be dosed with a chemical wash to prevent metal corrosion caused by the saltwater – it seems even the main rotors would be drenched with water during landings and take offs.

Something else I’m very curious about. As the S-61s were frequently coming under ground fire it was decided to mount a GMPG in the cabin but during trials the whole cabin and cockpit would be filled with gunsmoke and the plan wa abandoned – 20mm guns were fitted on Alouttee 3s instead. At first my guess was that the problem was due to the design only having a single sliding door and there being not enough ventilation to disperse the gunsmoke but I recently found out that several Sea King [which also has a single sliding door] operators had mounted GMPGs in their aircraft without encountering the same problem.