Spoke with a friend today who did some hoisting in a 139 as well... said the nose was up about 15 degrees usually in the hover, and this created quite an issue during overwater evolutions. Rotorwash was somehow sucked down in the front and along the belly of the chopper, which went straight down and created a very strong and odd current in the water. If the aircraft hovered over the swimmer for more than a few seconds, he would always end up getting pushed about 30 deg left off the tail, for a ways. The only way they could do it was come in and quickly drop the hook to the swimmer, then slide the ship away and stand off while he hooked up and/or got the victim ready to be winched. He's winched off a lot of platforms and said the 139 was by far his least favorite.
Nice chopper tho!
Mike