Cat. 3 investigation report: report concerning an occurrence with limited consequences, based on one or more statements not independently validated by the BEA.
This is a courtesy translation by the BEA of the Final Report on the Safety Investigation published in February 2021. As accurate as the translation may be, the original text in French is the work of reference.
Note: The following information is principally based on statements made by the instructor. This information has not been independently validated by the BEA.
1 - HISTORY OF THE FLIGHT
The instructor and the student pilot were carrying out runway circuits on runway 11 of Cuers-Pierrefeu aerodrome. The student was in command. The wind was calm and the weather conditions were good (CAVOK).
During the first runway circuit, the student was late in preparing the aeroplane in the downwind leg and lined up on final, high on the approach slope. The instructor helped him with the controls until touchdown, reminding him how to fly the plane during the flare.
The student completed the second runway circuit perfectly. He lined up on final on a normal approach slope at the right speed. At the beginning of the flare, the instructor helped him with the controls again and then let him fly until touchdown. The plane made a small bounce and landed on the right wheel. The instructor indicated that the student then made a right stick input, applied full power and then made a left pedal input. The instructor had the feeling that the student kept a tight grip on the controls.
The aeroplane veered off to the left onto the grass strip. The instructor reduced power and put the stick in neutral. He tried to correct the path with the hand rudder control but the aeroplane remained on its path. The student released the controls as the aeroplane crossed taxiway C1 of runway 11.
The plane violently struck the fence bordering the aerodrome. The left wing separated from the fuselage at the root, which disconnected the fuel line of the wing tank through which fuel flowed abundantly onto the ground. Moreover, the wing, folded backwards, interfered with the opening of the sliding canopy and prevented the evacuation of the aeroplane. The instructor sent an emergency radio message. Mechanics quickly arrived with a fire extinguisher. The aerodrome military firefighters came to evacuate the occupants shortly thereafter.
2 - DESCRIPTION OF HAND RUDDER CONTROL SYSTEM
As the instructor could not operate the rudder pedals, the aeroplane was equipped with a hand rudder control system (see Figure 1) on the centre console and a differential manual brake control (see Figure 2) on the left side of the cockpit. The student used the conventional flight controls, available in the left and right seat.
Figure 2: F-BULK manual brake control (Source: BEA)
3 - LESSONS LEARNED AND FEEDBACK
On this type of aeroplane, there is no steerable nosewheel. When the instructor took back the controls, he hesitated using the differential brakes, believing that, given the speed, the rudder would be effective enough to modify the aeroplane’s path and avoid collision with the fence. He believed that the use of the brakes would probably have allowed him to better control the aeroplane on the ground.