What happened
On 7 January 2018, a Piper PA-28-181 Cherokee Archer II, registration G-BSIZ, was conducting a training flight near Elstroll Aerodrome. The flight involved a student pilot practicing forced landing procedures at altitudes reaching 3,500 ft. During the return leg to the airfield, the aircraft descended to join the circuit for Runway 08.
As the aircraft descended to approximately 900 ft, the student pilot attempted to increase power by advancing the throttle, but the engine failed to respond. After unsuccessful attempts to restore power, the instructor took control of the aircraft. Following the execution of engine failure checklists and a MAYDAY call, the instructor maneuvered the aircraft toward a field located roughly one mile south of the airfield. The aircraft landed in a muddy, wet grass field. During the landing roll, the nosewheel lifted and then struck the ground again, causing it to detach. The resulting impact caused the propeller and nose to dig into the earth, forcing a 90-degree left turn and causing severe damage to the right wing. There were no injuries to the two crew members on board.
The investigation
The investigation focused on the cause of the engine's failure to respond to throttle advances. Examination of the aircraft revealed that the fuel tanks were not empty and no mechanical engine faults were identified. While the instructor reported that carburettor heat had been applied according to manufacturer procedures, the investigation looked into the possibility of induction icing.
Met Office data for the time of the incident showed an outside air temperature of approximately 0ºC, with a dew point just 0.5ºC below that temperature. This environmental condition indicated a high risk of icing.
Findings
- The engine power failed to increase when the throttle was advanced.
- Carburettor icing is the suspected cause of the power loss.
- Atmospheric conditions, specifically a temperature near 0ºC and a high dew point, created an environment susceptible to serious engine induction icing.
- The aircraft sustained extensive damage due to the nosewheel detachment and subsequent ground impact.