What happened
The pilot was operating under instrument meteorological conditions while receiving vectors from air traffic control for a visual approach to Hyde Field Airport. The last altitude assigned by ATC was 1600 feet, representing the minimum vectoring altitude for that specific area.
During the approach, the pilot radioed air traffic control to announce a descent to 1000 feet. ATC did not provide a response to this transmission. The aircraft continued its descent to 1000 feet and performed a 360-degree turn. As the aircraft began a second circle, it disappeared from radar. The final recorded altitude for the flight was 800 feet, after which the airplane descended into terrain without further warning or communication from ATC.