Introduction
On 7 September 2023, at approximately 16:06 UTC, a Raj Hamsa X Air aircraft (registration EI-CXC, serial number KIT 333) experienced an engine power interruption shortly after take-off from Limetree Airfield, County Laois, Ireland. The aircraft was conducting a general aviation flight with one pilot and one passenger on board. The passenger sustained a back injury and the aircraft suffered substantial damage.
History of the Flight
Prior to the accident flight, the aircraft owner had fully drained the fuel tanks in the summertime to remove old fuel. Four days before the accident, the aircraft was refuelled with motor gasoline purchased from a petrol station, mixed with two-stroke oil for the two-stroke engine. On the afternoon of the accident, the owner performed engine running and taxi runs, including power checks, for approximately 25 to 30 minutes. The engine was then shut down for about 30 minutes before the flight. No anomalies were noted.
The pilot conducted a thorough walk-around inspection before boarding, accompanied by the passenger. The pilot inspected the engine and was satisfied with the integrity and attachment of the spark plug leads. After boarding, the engine was started and allowed to warm up at idle (approximately 2,200 RPM) for about five minutes. The pilot noted that the brakes were not effective at holding the aircraft at engine speeds above about 2,500 RPM.
At 16:04 hours, the pilot taxied to Runway 19, described as an uphill runway with a hill on the extended centreline and a large tree to the right. The temperature was approximately 26°C. During the take-off ground roll, engine parameters were in the green, and the engine achieved its expected maximum speed of around 6,300 RPM. The aircraft became airborne about halfway along the runway.
Within seconds after take-off, while the aircraft was 50 to 60 feet above the hill terrain, the engine 'coughed' several times and the aircraft began to sink. The pilot immediately looked for a landing area and observed two fields to the right of a farmhouse with a gap in the hedge between them. He reduced the throttle to idle and nosed the aircraft down towards the gap. The aircraft landed 20 to 25 metres before the gap at about 50 to 55 mph. It struck a stake and an electric cattle fence at the gap, causing the right wing strut to impact. The aircraft spun to the right, the right main wheel and nosewheel separated, and it came to rest in the next field. The pilot turned off the magnetos and battery master switch. The passenger reported back pain upon exiting, and an ambulance was summoned. The passenger was taken to hospital and later released.
Wreckage Examination
The wreckage was recovered from the accident site and mounted on a trailer, secured with a tie. An inspection of the engine revealed that the power interruption was due to a cold seizure in the front cylinder and a loss of clearance in the rear cylinder.
Investigation
Both the pilot and the owner notified the Air Accident Investigation Unit (AAIU) on the day of the accident. The following day, a team of three AAIU inspectors travelled to Limetree Airfield and commenced an investigation. The aircraft's engine, a Rotax 582/48, was examined to determine the cause of the power loss.