What happened
On 22 July 2019, a Cessna 172S, registration PK-WUG, was conducting a flight training exercise from Cakrabhuwana Airport to the Indramayu Training Area. The flight was operated by Angkasa Aviation Academy and involved two student pilots, with one acting as the pilot in command.
While the flight plan specified a cruising altitude of 2,000 feet, the aircraft began descending as it approached the southern boundary of the training area. Driven by a desire for sightseeing, the crew chose to fly over the Cimanuk River. During this maneuver, the aircraft's altitude dropped significantly, reaching approximately 140 feet above the surface. While traversing the river, the aircraft struck three power line cables, causing it to crash into the water.
Following the impact, both occupants attempted to evacuate the wreckage. During the process of reaching the riverbank, the student pilot in the right seat drowned, resulting in one fatality, while the pilot in command sustained minor injuries.
The investigation
The investigation examined the flight path using GPS Garmin G1000 data, which confirmed the unauthorized descent. Investigators looked into the academy's oversight capabilities and found that the school's flight-following subscription had lapsed, leaving the aircraft unmonitored in real time. Furthermore, while the aircraft's GPS logs were periodically downloaded to an engineering server, this data was not being analyzed to identify safety violations or altitude deviations.
Findings
- The pilot decided to descend below the minimum safe altitude because there was no active supervision or real-time monitoring of the flight maneuvers.
- The crew was unaware that power lines crossed the river at that specific location.
- The academy failed to utilize available flight-monitoring tools, which could have detected the altitude deviation and prevented the accident.
- The academy's safety management system did not effectively use stored flight data to identify and correct non-compliant flight profiles.