The aircraft and its two pilots belonged to the Volunteer Air Corps (FFK) and participated on Friday afternoon in an exercise on behalf of the navy.
The plane was supposed to land at an airfield near Limmaren, but ended up in the water and sank to the bottom.
On Monday, the plane was salvaged, with one of the deceased pilots still on board.
During the rescue operation on Friday, only one of the pilots could be lifted out of the water and transported to the hospital. But the other pilot could not be picked up by divers and has therefore remained in the plane.
How the accident occurred is still unclear and the two pilots – who were the only ones on the plane – are described as experienced.
The plane was salvaged with the help of flotation cushions and a helicopter, and will now be analyzed by the Swedish Accident Investigation Authority, which is investigating the incident.