What happened
On 25 June 2021, a Cessna 208B, registered as PH-FST, was undergoing scheduled maintenance at a hangar. During the pre-flight maintenance process, technicians observed inconsistent and high Exhaust Gas Temperature (EGT) readings while the engine was running on the ground. To address these fluctuations, the maintenance team identified a potential fault in the propeller governor's magnetic pick-up.
A mechanic, working under the oversight of a licensed engineer, proceeded to replace the component. While the initial installation steps were completed according to the maintenance manual, the technician failed to perform the required system voltage tests outlined in steps five through eight of the procedure. Following the installation, a static engine test and a Single Red Line (SRL) check were conducted, which appeared to confirm that the EGT readings were stable.
After the maintenance was concluded, the pilot taxied to a nearby facility to collect seventeen passengers for a skydiving flight. The aircraft departed from runway 26, but during the initial climb, the engine suffered a sudden loss of power at an altitude of roughly 400 feet. The pilot was forced to execute an emergency landing in a nearby field. The impact caused substantial damage to the aircraft's propeller, landing gear, wings, and fuselage. Among the passengers, one person sustained minor injuries.
Findings
- The maintenance technician failed to perform the mandatory system voltage tests following the replacement of the magnetic pick-up.
- Incomplete verification of the electrical installation preceded the engine failure during the takeoff phase.