Gathering info:
Bergung nach Hubschrauberabsturz in Ostsee | NDR.de - Regional - Mecklenburg-Vorpommern
..suddenly ditched while on approach to vessel upon which a docter should have been dispatched via winch. The whole thing was an emergency exercise.
Hubschrauber-Absturz: "Wir stehen vor einem Rätsel" | STERN.DE
one pilot,the doctor and the medical assistant are dead. The sea at the location of the accident has a depth of 21ft.
It was a weekly training exercise. The doctor has been lowered onto the ship and brought up again twiche, then during departure the helicopter ditched at 2km distince from the ship.
both pilot were experiences (9500h resp. 7000h incl. OffShore work)
Tödlicher Einsatz über der Ostsee: Hubschrauber versinkt im Meer - n-tv.de
4°C water temp, only on of the pilot survived. Both managed to get out of the helicopter, one of them died from severe injuries.
but no clues as to the cause of the accident.
edit:
Maschine wird geborgen: Drei Tote bei Hubschrauber-Absturz in der Ostsee - Aus aller Welt - FOCUS Online - Nachrichten
According to eyewittness reports the helicopter ditched on his "thrid approach attempt"
Vor der Küste Mecklenburg-Vorpommerns: Drei Tote bei Hubschrauberabsturz - Unglücke - FAZ
ditched app. 4km east of Darßer Ort (village?) in the vincinity of the wind park Baltic 1. Againg eyewitnesses reporting "thrid approach attempt".
"..specially equipped for off shore service.." here are the floats:
Tödlicher Hubschrauber-Absturz gibt Rätsel auf | shz.de
amazing how much grossly contradicting information one can find in the press.