What happened
On September 10, 2016, a flight instructor was conducting a training flight for a PPL(A) student in a Diamond DA20-A1 Katana. The training session was focused on familiarizing the student with the engine differences between the Katana and the C1 model.
During the final phase of the takeoff roll on grass runway 24, the crew felt a slight jolt in the cockpit. While the takeoff roll continued without further interruption, the crew received radio communication from a winch operator flying nearby, reporting that the right main landing gear fairing appeared to have detached. After performing a low pass over a glider square, the crew received further confirmation that the landing gear remained structurally intact despite the missing fairing. The aircraft landed at Suwałki Airport without further incident.
The investigation
The investigation examined the remains of the fairing found attached to the right gear strut, as well as debris recovered from the airfield. The inspection revealed that several small mounting bolts had unscrewed, leaving the fairing held in place only by a single main bolt on the wheel axis extension.
Further inspection of the left main gear fairing revealed a loose bolt, prompting the crew to remove the fairings from both main wheels and the nose gear to prevent further detachment. The operator also noted that the bolts and spring washers used in the assembly were not the specific parts dedicated to these fairings.
Findings
- The primary cause of the incident was the improper tightening of the bolts securing the main landing gear fairing, which allowed them to unscrew and cause the component to detach.
- The use of incorrect bolts and spring washers contributed to the failure of the attachment mechanism.