Approach and Landing
Prior to departure, the pilot received a weather briefing indicating rain and wet roads at the destination, but no mention of ice. During the approach to the destination airport, the runway appeared "wet," so a normal approach and landing was executed. The airplane touched down at 110 knots, at which point the pilot deployed lift dump and applied the brakes.
Loss of Braking Action
Unable to obtain braking action, the pilot attempted to slide the airplane left and right to gain traction, but these efforts were unsuccessful. The airplane departed the south end of the 4,370-foot-long runway, went over the edge of an embankment, and came to a stop next to a levee. No pre-impact malfunctions were reported.
Runway Condition and Manufacturer Guidance
The Manufacturer Approved Airplane Flight Manual Supplement for Airplanes Operating on Wet and Contaminated Runways states that operations on runways contaminated with ice or wet ice are not recommended and provide no operational information. Using the supplement, the calculated landing distance on a wet runway was approximately 3,400 feet, while on an uncontaminated runway it was approximately 2,800 feet. The prescribed landing speed (Vref) was determined to be about 111 knots. A braking action report for the private airfield's runway did not exist, nor was one required.
Outcome
The aircraft sustained no reported pre-impact malfunctions. The pilot's attempt to regain traction was unsuccessful, resulting in the runway excursion.