Incident
On 27 August 2003 at 17:30 local time, an aircraft with registration LY-KAE experienced an accident during landing at Målöga, Gråbo, O county, Sweden. The landing was performed with a tailwind component. After touchdown, the aircraft nosed over. The two occupants, pilot and one passenger, left the aircraft unhurt. No fire occurred. The lower right wing, tailplane, rudder, and propeller were damaged.
Aircraft and Pilot
The aircraft was a PZL-Mielec (Antonov) AN-2, a large single-engined biplane with a maximum capacity of 12 passengers. It was privately owned and held a special valid certificate of airworthiness. The pilot, a 59-year-old man, held an A certificate with Lithuanian validation. He had 1,450 total flying hours, including 73 on type. In the previous 90 days, he had logged 34 hours, 19 on type. The flight manual requires for VFR operations a crew of a pilot and a navigator or flight mechanic; however, the flight was operated with only a pilot.
Airfield
Målöga is a private grass airfield approximately 310 meters long and 300 meters wide. The runways are oriented 240°/60° (runways 24/06). The airfield slopes upward toward the end of runway 24. At that end, a thin line of trees about 10 meters high exists, and at the end of runway 06 a single tree of similar height. Strips of loose sand cross the runways at intervals of about 30 meters. A wooded ridge runs along the southern side. Typically, takeoffs are from runway 06 (downhill) and landings on runway 24 (uphill). On this flight, the takeoff was with a headwind and the landing with a tailwind.
Flight and Landing
The pilot conducted a local flight with a passenger. The aircraft's landing weight was approximately 4,175 kg. The weather at the time, according to SMHI analysis, was northerly wind about 10 knots (about 5 m/s), giving a tailwind component of approximately 2.5 m/s for runway 24. The pilot stated that he braked too hard after touchdown. Touchdown occurred about 125 meters into the runway. The main wheel tracks were about 80 meters long and indicated that the wheels were locked from touchdown or shortly thereafter until the aircraft nosed over. No tail wheel track was observed. The remaining runway length after touchdown was about 185 meters.
According to the flight manual, sudden braking directly after touchdown may lead to aircraft turnover; braking should be smooth and in phases. The center of gravity (CG) was at approximately 20% MAC, which is within the acceptable range (17-32% MAC) but forward of the recommended range (23-27% MAC). The flight manual provided landing roll distances but not landing distances from a height of 15 meters.
Investigation
The Swedish Accident Investigation Board (SHK) investigated. The investigation found that braking after touchdown started too early and was too hard. The forward CG position reinforced the tendency to flip over. The pilot likely braked hard because touchdown occurred further into the runway than anticipated, but the remaining runway length was sufficient with a margin of almost 50%, suggesting inadequate flight planning. The pilot's assessment of the airfield's suitability was hampered by the lack of landing distance information from 15 meters in the flight manual. The shortage of crew (only one pilot) did not affect the course of events.
Probable Cause
The accident was caused by the fact that braking after touchdown started too early and was too hard.