What happened
Following takeoff, the crew encountered an issue with the aircraft's flight control systems that prevented normal operation of the high-lift devices. Specifically, the pilots were unable to retract the spoilers located on the right wing. Due to the resulting aerodynamic drag and performance degradation, the decision was made to return to the departure airport for a landing. The approach and touchdown proceeded without further incident, and the aircraft landed safely.
The investigation
A post-incident inspection of the aircraft was conducted to determine the root cause of the mechanical failure. Technicians examined the spoiler retraction mechanism on the right wing. The examination identified physical obstructions within the area surrounding the bellcrank assembly. This blockage prevented the proper movement of specific spoiler panels, namely number 1, number 4, and number 5 on the right-hand side.
Findings
The mechanical failure was attributed to environmental contamination rather than a design flaw or maintenance error. Rust and foreign debris were found accumulated in the bellcrank area. This accumulation physically inhibited the retraction mechanism, causing the affected spoilers to remain extended by approximately four to five inches after the command to retract was issued. The presence of these contaminants effectively locked the spoilers in a partially deployed position.