| Occurrence Briefs are concise reports that detail the facts surrounding a transport safety occurrence, as received in the initial notification and any follow-up enquiries. They provide an opportunity to share safety messages in the absence of an investigation. Because occurrence briefs are not investigations under the Transport Safety Investigation Act 2003, the information in them is de-identified. |
What happened
On the morning of 23 October 2024, an Air Tractor AT-504 (Figure 1) was on approach to land at a private aircraft landing area, about 28 km south-east of Duaringa, Queensland, when a water bottle fell onto the floor in the cockpit and rolled in front of the copilot’s left rudder pedal. The pilot decided to abort the landing and climb to a safe altitude to try to retrieve the bottle before attempting another approach. However, during the climb and after retracting the flaps, the aircraft suddenly yawed sharply to the left.
Figure 1: Air Tractor AT-504
Source: Operator
The pilot recalled attempting to correct the yaw by depressing the right rudder pedal, but this was ineffective. While trying to regain control, the pilot couldn't find the bottle (Figure 2). Realising that the aircraft was close to entering a spin, the pilot chose not to increase power, as this would have worsened the yaw and required more opposite aileron.
The pilot chose to attempt a landing, however collided with trees short of an open field (Figure 3). The impact with trees caused the aircraft to veer left and overturn, eventually coming to rest upside down. The pilot, who sustained minor injuries, was able to exit before a fire consumed the aircraft following the impact (Figure 4).
Figure 2: Air Tractor AT-504 cockpit and primary flight controls
Source: Operator, annotated by the ATSB
Figure 3: Aircraft landing area with depiction of aircraft track
Source: Google Earth, annotated by the ATSB
Figure 4: Air Tractor AT-504 wreckage
Source: Operator, annotated by the ATSB
Safety message
This accident highlights the serious risks of loose items, known as foreign object debris (FOD), in the cockpit. Objects such as water bottles, phones and other loose objects in a cockpit can dislodge and interfere with flight controls during critical phases of flight.
Pilots and operators are encouraged to conduct thorough pre-flight checks to find and proactively secure any loose items in the cockpit throughout all phases of flight. Implementing these practices can prevent FOD interference with flight controls, ensuring a safer environment for all phases of flight.
Similar issues were noted in the US National Transportation Safety Board (NTSB) investigation report IAD05LA072, where an unsecured pen and jar obstructed the flight controls, resulting in a loss of control.
About this report
Decisions regarding whether to conduct an investigation, and the scope of an investigation, are based on many factors, including the level of safety benefit likely to be obtained from an investigation. For this occurrence, no investigation has been conducted and the ATSB did not verify the accuracy of the information. A brief description has been written using information supplied in the notification and any follow-up information in order to produce a short summary report, and allow for greater industry awareness of potential safety issues and possible safety actions.