The pilot died when a small plane crashed in Lake Constance on Thursday.
According to the police in the canton of St. Gallen, the 72-year-old Swiss may have been traveling alone.
The police could only recover the dead pilot.
The plane crashed in the afternoon near Altenrhein Airport near Staad.
The crash site was said to be in shallow water about 50 meters from the shore.
The pilot had previously taken off from this airport, had reported technical problems and therefore wanted to return to the airport.
The cause of his technical problems was initially unknown.
The plane is expected to be recovered Thursday evening.
The investigations into the course of the accident are being conducted by the Swiss Safety Investigation Board, SUST for short.