Accident Overview
On 27 December 1980, at approximately 1640 local time, a Piper PA-38-112 Tomahawk, registration HB-PDT, crashed into Lake Zurich about 1 kilometer from the shore near Kehlhof, Stäfa. The pilot, the sole occupant, was killed upon impact and the aircraft was destroyed. No third-party damage occurred.
Flight Details
The pilot, a Swiss citizen born in 1950, held a private pilot license issued on 11 August 1978 and renewed on 31 August 1980. At the last medical examination on 6 August 1980, he was found fit without restrictions. His total flight experience at the time of the last license renewal was 81 hours and 31 minutes, with 409 landings.
The flight originated from Speck-Fehraltorf airfield at 1610 local time. The pilot planned a VFR flight to Wangen-Lachen. Prior to departure, the aircraft had approximately 8 US gallons of fuel; no refueling occurred. The flight was intended to ferry the aircraft from Speck-Fehraltorf to Wangen after a 1000-hour inspection performed on 24 December 1980.
After takeoff at 1608, the pilot contacted Wangen. At 1615, a flight instructor in Wangen instructed the pilot to return to Speck-Fehraltorf due to deteriorating weather. The pilot acknowledged, reporting position over Pfäffikon at 3000 feet. At approximately 1630, the pilot reported position over Rapperswil at 2500 feet. When asked if he could see Wangen airfield, he replied negatively. The flight instructors detected distress in his voice and reiterated the instruction to return to Speck-Fehraltorf, advising a heading of 350° and maintaining 2500 feet if possible. The pilot acknowledged. Shortly thereafter, radio contact was lost.
Weather Conditions
At the accident site, weather reports indicated 6–8/8 cumulus and stratocumulus clouds with bases at 800–1200 meters, snow showers, visibility 10 km or more but reduced to 1 km in showers. Wind was from the northeast at 5–10 knots with gusts to 20 knots. Temperature was -1°C, dew point -2°C. Local bise turbulence and poor visibility in snow showers were noted. Sunset occurred at 1640 local time.
Eyewitnesses near the accident site between Uerikon, Stäfa, and Kehlhof reported extremely poor visibility due to heavy snow showers, estimated at 50–100 meters. A former pilot near Kehlhof estimated visibility at 80–100 meters, while a fisherman on the lake reported only 50 meters. The approach of darkness further reduced visibility.
Wreck Examination
The aircraft was extensively damaged, limiting the examination. Key components such as the propeller, altimeter, and several other parts were not recovered. The cockpit instruments showed: RPM indicator blocked at 2700 rpm, clock stopped at 1640, defroster off, fuel selector left 1/4 and right 0, anti-collision lights on, pitot heat off, carburetor heat on, ignition switch on both, transponder on code 2760, and mixture rich. The attitude indicator was blocked showing a 45° right bank. The directional gyro indicated 265°. Deformations and the horizon indication suggested the aircraft was in a right turn at impact with high speed.
Visual inspection of flight control connections, push-pull rods, cables, and bellcranks revealed no pre-existing defects. All fractures were consistent with overload from impact.
Cause
The accident was attributed to collision with the lake surface after flying into a zone of poor visibility during a VFR flight.