History of the Flight
On 22 July 2019, a Cessna 172S registered PK-WUG departed from Cakrabhuwana Airport in Cirebon for a mutual training flight to the Indramayu Training Area. The flight plan indicated a cruising altitude of 2,000 feet. The exercise was part of the C-14 Stage, which included mutual precision rate one turns, compass error, and performance maneuvers. No aircraft system malfunctions were reported before departure.
The aircraft carried two student pilots. One acted as pilot-in-command (PIC), while the other occupied the right seat. At 1358 LT, the aircraft took off from runway 04. After passing over the CA checkpoint, the crew contacted Kertajati Tower and were instructed to climb to 2,000 feet.
GPS data showed the aircraft descending while flying over the southern boundary of the training area. At 1425 LT, the aircraft passed through 750 feet and continued descending while flying over the Cimanuk River. Approximately one minute later, the aircraft struck power line cables and crashed into the river.
Aircraft and Operator Information
PK-WUG was a Cessna 172S operated by Angkasa Aviation Academy (AAA), a flight training organization. The aircraft was equipped with a GPS Garmin G1000 system that recorded flight data. The operator had established standard operating procedures and a safety management system, but the investigation noted that available means to monitor training flights were not utilized.
Wreckage and Impact
The aircraft struck three power line cables strung across the Cimanuk River. Wreckage examination revealed that one cable was caught in the main landing gear struts. The aircraft came to rest in the river and was later recovered. The vertical stabilizer was damaged, consistent with cable strike.
Injuries
During evacuation, the safety pilot drowned and was fatally injured. The PIC sustained minor injuries.
Probable Cause
The investigation identified two contributing factors: (1) The available means to monitor flight training activities had not been utilized, allowing the aircraft to descend below the minimum safe altitude without detection. (2) The aircraft descended below the minimum safe altitude, and the pilots were unaware of power line cables crossing the river, resulting in the aircraft striking three cables.