Event Sequence
On Saturday, 17 October 1998 at approximately 13:55 local time, an amateur-built PIK-21 Super Sytky (registration OH-XME) suffered an accident during takeoff from Nummelan airfield. The aircraft, owned and built by the pilot, had completed seven test flights by an experienced test pilot since its completion in autumn 1998, with the accident flight being the owner's first flight. The test pilot had advised the owner to climb to 1000-1500 feet and practice turns to familiarize with the aircraft's handling.
The owner conducted a pre-flight inspection and found the aircraft serviceable, with about 20 liters of fuel. The takeoff commenced from runway 22, a grass surface between asphalt sections. A witness reported that after throttle application, the aircraft wobbled laterally for 10-15 meters, then straightened. As speed approached liftoff, the tail rose and the aircraft oscillated vertically, which then subsided. The aircraft lifted off, likely at the correct speed.
Initially climbing straight, the aircraft soon began a slight right turn and vertical oscillations. It then turned more sharply to the right toward a wooded area, banking erratically. The maximum altitude reached was about three meters. During the oscillations, the main landing gear contacted the ground, detaching along with part of the fuselage structure to which the rudder pedals were attached. The aircraft overturned, coming to rest inverted and rotated about 45 degrees to the right. The engine and fuel tank also detached during the impact.
The pilot, restrained by a four-point harness, struck his face on the instrument panel, sustaining injuries to his mouth area. He managed to lift the fuselage enough to exit the cockpit quickly. Electrical wires from the battery shorted and burned their insulation, but the fire self-extinguished when the wires burned through.
Aircraft Information
The PIK-21 Super Sytky was a single-seat, mid-wing, wood-construction aircraft with a fixed tailwheel landing gear. It was amateur-built by the owner. The takeoff weight was 306 kg, within the maximum allowable 320 kg. The aircraft had a short control stick mounted at the right side of the cockpit, angled slightly left.
Pilot Information
The pilot was a 59-year-old male with a private pilot license issued in spring 1971. His total flying experience was 262 hours and 50 minutes, with 601 landings. In the previous two years, he had flown only 2 hours and 50 minutes, all on Cessna 152 aircraft for check flights. He had flown two tailwheel types (PIK-11 and Stieglitz) for a total of 5 hours, but those flights occurred in 1972. The majority of his flying was on Cessna 150/152 models with control yokes.
Weather
At the time of the accident, wind at Nummelan airfield was from 220-240 degrees, light and steady. Temperature was approximately 8°C. The sun was shining through a thin veil of clouds.
Injuries and Damage
The pilot suffered minor injuries. The aircraft was severely damaged; the landing gear, engine, and fuel tank detached, and the fuselage structure was compromised.
Investigation Findings
The investigation determined that the aircraft's controls were exceptionally sensitive. The test pilot described the elevator as very sensitive with no feel, the rudder insensitive yet very sensitive, and the ailerons effective with little force required. The pilot had been warned about the sensitivity, but he noted he had underestimated the degree, expecting centimeters of movement rather than millimeters.
The pilot's recent flying experience was limited to Cessna 152 aircraft with yoke controls, which require larger control inputs. The PIK-21's sensitive controls and tailwheel configuration presented a significant transition challenge, especially without type-specific training due to the single-seat design.
The cause of the accident was determined to be the sensitivity of the aircraft controls and the pilot's insufficient flying experience for this type of aircraft, leading to overcontrol and subsequent loss of control during takeoff.