Accident Details
On Friday, 18 May 1973, at 1706 hours, a Cessna 177 RG "Cardinal" (registration HB-CVH) departed from Zurich Airport for a private VFR flight to Wangen-Lachen with three passengers. After takeoff from runway 28, the aircraft initiated a left turn. During the turn, witnesses reported that the aircraft climbed poorly and flew slowly. The aircraft then stalled from a low altitude and crashed in a steep angle near holding position 10, just outside the airport boundary in the municipality of Rümlang. All four occupants were killed, and the aircraft was destroyed. Minor damage to crops occurred.
Aircraft and Pilot Information
The aircraft, a four-seat single-engine high-wing monoplane with retractable landing gear, was built in 1971 by Reims Aviation. It was powered by an Avco Lycoming IO-360-A1B6 engine producing 200 hp. The pilot held a private pilot license issued on 7 February 1972, with endorsements for flaps, variable-pitch propeller, and retractable gear. His total flight experience was 80 hours 32 minutes, with 5 hours 58 minutes on the accident type. His last flight on the accident type was on 25 August 1972. The aircraft's weight and balance at the time of the accident were within limits.
Weather and Navigation
At the time of the accident, the weather was clear with a ceiling of 5000 feet and light Bise turbulence. Surface wind was from 040° at 8 knots; however, the tower reported wind 060° at 7 knots, which gave a tailwind component of about 5 knots for takeoff on runway 28. The sun was at azimuth 270°, elevation 27°, potentially causing glare during the left turn.
Accident Sequence
The pilot filed a flight plan for a local flight with departure at 1630, but actually departed at 1706. After taxiing, the aircraft was cleared for takeoff on runway 28. The takeoff roll was normal; the aircraft lifted off near the intersection with taxiway 8, after approximately 350 meters. The climb was shallow along the runway centerline until about the intersection with runway 16/34, then entered a shallow left turn. Witnesses estimated the height at the start of the turn at 20 to 50 meters. The aircraft did not gain altitude and stalled, crashing at 1706:30. Examination of the wreckage revealed the left flap fully retracted and the right flap fully extended. The elevator trim was set to full nose-down, the rudder was in a left-turn position, and the elevator was in full up position. The propeller blades showed signs of power at impact.
Probable Cause
The investigation determined the probable causes to be: 1. Undershooting the minimum speed when overflying obstacles with low height reserve; 2. Lack of flight experience and insufficient training; 3. Difficult takeoff procedure due to the significant shortening of the flight path to the first obstacles.