Flight History
On 9 March 1974, at 1106 Central European Time, the pilot of a Cessna F 177 RG (registration HB-CDK) departed from runway 30 at Bad Ragaz airfield with one passenger for a private sightseeing flight. Prior to departure, he had completed two training circuits. The flight route included Bad Ragaz, Flums, Weisstannental, Braunwald, Flims, Chur, and back to Bad Ragaz.
Upon return, the pilot overflew the airfield to check wind direction. Finding no clear wind indication, he decided to approach runway 30. During the final approach, he noted a foehn tendency (tailwind) and deemed landing inadvisable, initiating an overshoot. After the overshoot, he chose to land on runway 12.
Heavy turbulence was reported in the Sarganser valley. During the approach to runway 12, two witnesses near the hangar (runway 12 threshold) observed that the landing gear was not extended and attempted to signal the pilot, but were not seen. In the final approach, just before the threshold, the pilot noticed the red landing gear warning light indicating the gear was retracted. He decided to perform a belly landing on the grass. The aircraft touched down approximately 180 meters past the threshold of runway 12 and about 1 meter from the left edge. It slid about 116 meters and came to rest 4 meters from the left edge of the runway.
Findings
The pilot held a valid private pilot license with endorsements for limited radiotelephony, flaps, controllable-pitch propeller, and retractable landing gear. No relevant health issues were reported to the investigator, and no previous accidents or incidents were recorded in the preceding five years. The aircraft was certified for flight. Examination revealed that the landing gear warning horn was inoperative. The weather was characterized by foehn wind and turbulence.
Assessment
According to the investigation report, the pilot had forgotten to extend the landing gear, likely because the change of runway (from 30 to 12) and the severe turbulence in the Sarganser valley had put him under pressure. The inoperative landing gear warning horn prevented him from being alerted when he reduced power. The pilot made a misjudgment by continuing the landing rather than initiating a go-around after spotting the red gear light just before the threshold.