What happened
On 10 November 2022, a Link Airways Saab 340B, registration VH-VEQ, was undergoing preparations for a scheduled flight from Canberra to Sydney. During the pre-flight process, the first officer performed inspections on the engines but failed to remove a propeller strap from the left engine. Additionally, a strap extension, which is intended to be attached between the airstairs and the propeller to prevent passengers from walking under the blades, was not installed. The absence of this extension meant the cabin door could be closed despite the strap still being in place.
During the engine start sequence, the left engine experienced a delay in rotation because the propeller was still restrained by the strap. The torque from the engine eventually caused the pins securing the strap to the engine cowling to fail. As the aircraft became airborne, the strap was thrown from the blade and struck the fuselage. While the strap itself became embedded in the aircraft, broken cowling pins entered the cabin, striking a passenger's leg and causing a minor injury.
The investigation
The investigation examined the pre-flight procedures, the roles of the ground handling staff, and the mechanical failure of the strap pins. Investigators looked into why the flight crew and the ground dispatcher failed to notice the attached strap. The inquiry also reviewed the training provided to the ground handling company, Swissport, and the maintenance condition of the propeller straps within the Link Airways fleet.
Findings
Several contributing factors were identified that allowed the strap to remain attached during departure:
- The first officer did not install the strap extension, which would have prevented the cabin door from being closed while the propeller strap was still active.
- The propeller strap lacked a required visibility aid, such as a streamer, making it difficult to detect.
- The ground dispatcher did not perform a full walk-around of the aircraft, and the training provided to dispatchers did not sufficiently cover the importance or appearance of propeller straps.
- Training for the dispatchers did not adequately explain the function of the equipment, and the dispatcher's view was obscured by sunlight.
Safety action
Link Airways has implemented several changes, including updating flight and cabin crew manuals to include specific checks for propeller straps and extensions. The airline also updated its training guidance for ground handlers and initiated audits of Swissport's dispatch procedures. Swissport has since instructed all ramp staff that walk-arounds are mandatory for Saab aircraft and is working to refine dispatcher responsibilities.