What happened
On February 22, 2009, a Pioneer 200 ultralight aircraft, registration CS-UNF, departed from Pista da Lezíria for a recreational flight to Beja. Approximately five minutes into the flight, the engine began operating irregularly. Faced with a partial loss of power, the pilot was forced to perform an emergency landing on the asphalt runway of the Alcochete Shooting Range (Campo de Tiro de Alcochete). At the time of the landing, the runway was being used by a group of people practicing model aircraft flying. The pilot and the passenger, who was also the aircraft owner, exited the aircraft uninjured, and no damage was sustained by the aircraft or third parties.
The investigation
The investigation focused on the engine's ignition system, which utilizes two redundant magneto coils mounted on the flywheel. Maintenance personnel identified that the engine malfunction originated from the distribution rotors. Upon inspection, it was discovered that the rotors currently installed (manufactured by INTERMOTOR) showed excessive internal wear and white powder residue.
Comparing the faulty rotors to the previous set (original Japanese-made rotors) revealed significant differences. The original rotors had operated for 300 hours without issue, whereas the newer INTERMOTOR rotors had failed after only 35 hours of operation. The investigation noted that the newer rotors lacked the quality markings of the originals and featured a design that did not account for premature wear. The investigation also ruled out installation errors, as the component's assembly is straightforward and does not permit incorrect mounting.
Findings
- The engine experienced a partial power loss due to premature wear of the ignition system distribution rotors.
- The faulty rotors were installed during a 300-hour inspection approximately 10 months prior to the incident.
- The replacement rotors, manufactured by INTERMOTOR, demonstrated significantly lower durability compared to the original Japanese-made components.
- Meteorological conditions were clear with light winds and did not contribute to the event.
Safety action
- It is recommended that the National Civil Aviation Institute (INAC) request operators of Jabiru 2200 engines to inspect and replace INTERMOTOR-manufactured distribution rotors, preferably with the original PII0632N part number.