What happened
On June 17, 2018, at approximately 13:00 LMT, a Moran 1s5 Replica ultralight aircraft was participating in a flight display at Katowice Muchowiec Airport (EPKM). The aircraft, operated by a private user, was part of a Czech reconstruction group performing WWI-era replica flights. Following the conclusion of the airshow, the crew had refueled their aircraft using fuel purchased from a nearby petrol station.
As the aircraft taxied onto the grass runway for departure, the pilot initiated a takeoff roll from the midpoint of the runway. Shortly after rotation, the engine began to run unevenly, characterized by audible-misfiring. At an altitude of approximately 40 meters, the pilot executed a 180-degree turn to perform an emergency landing on the grass strip on the southern side of the airfield. During the descent, the aircraft lost airspeed and experienced a hard touchdown, which caused the right main landing gear to collapse. The aircraft subsequently struck the ground with the right wingtip and entered a right-hand circle.
Neither the pilot nor the passenger sustained any injuries during the incident.
The investigation
The PKBWL examined the aircraft, the engine, and the fuel system. The engine was removed and sent to the manufacturer for inspection. Additionally, fuel samples were taken from both the aircraft's fuel tank and the fuel filter for visual inspection and assessment. The investigation also reviewed the pilot's credentials and the aircraft's airworthiness documentation.
Findings
- The investigation determined that the engine's irregular operation was caused by a faulty fuel installation.
- Visual inspection of fuel samples from the tank and filter confirmed the fuel was clean.
- The other three aircraft in the group that used the same fuel batch experienced no engine issues.
- The pilot held the necessary licenses and ratings for the flight.
- The VERNER engine installed on the aircraft did not possess a valid certificate.
- The aircraft's Certificate of Airworthiness (Technický Průkaz) had expired on June 11, 2018.
Due to the fact that the aircraft was being operated in violation of Polish aviation regulations regarding airworthiness, the PKBWL decided to discontinue further investigation of the incident.