Beechcraft 35-B33 Suffers Control Link Failure at Griffith

The Australian Transport Safety Bureau (ATSB) has launched a formal inquiry into a serious incident involving a Beech Aircraft Corp 35-B33, registered as VH-NEW, which occurred at Griffith Airport in New South Wales (NSW) on May 11, 2026. During the initial climb phase of a dual instructional flight, the flight crew reported significantly reduced effectiveness of both the ailerons and elevators. The crew successfully managed the aircraft, though the event has prompted a broader look at maintenance protocols for this aircraft type.

Investigation Findings

Preliminary inspection of the aircraft revealed that a bolt had liberated from the control torque link. The ATSB determined that the failure resulted from a missing split pin, a critical secondary locking device designed to prevent the nut from backing off the bolt during flight. The incident aircraft, identified by serial number CD-615, was operating under a Part 141 flight training program at the time of the occurrence. The ATSB has formally classified this event as a 'Serious Incident' and expects to publish its final investigation report under reference number AO-2026-078 by the fourth quarter of 2026.

Regulatory and Industry Context

This incident highlights ongoing concerns regarding human factors in aviation maintenance. The Civil Aviation Safety Authority (CASA) enforces strict airworthiness standards under Civil Aviation Safety Regulations (CASR) Part 42/43, which mandate the use and independent inspection of locking mechanisms on primary flight control linkages. Industry trends indicate that aviation authorities globally are placing increased focus on 'errors of omission' during maintenance, specifically the failure to install or secure secondary fasteners. Experts emphasize that independent dual-inspections for flight controls are essential to mitigate the risk of single-point mechanical failures that can lead to a total or partial loss of control.

Historical Precedents

The mechanical failure mechanism observed in this incident bears a striking resemblance to historical aviation accidents involving compromised flight control linkages. In November 2006, an Australian Army S-70A-9 Black Hawk accident resulted in the loss of the aircraft and multiple fatalities. An investigation into that event found that a missing split pin allowed a castellated nut to unwind, causing bolt extraction and a subsequent loss of control. Similarly, a 2011 incident involving an Embraer ERJ-190 (VH-UYB), which experienced a torque tube disconnection, underscored the necessity of rigorous adherence to maintenance task cards and the verification of locking hardware. These precedents illustrate the critical role that simple fasteners play in the safety of complex flight control systems.

Stakeholder Impact

For the Part 141 flight training operator of VH-NEW, the incident necessitated the immediate grounding of the aircraft to facilitate a comprehensive engineering inspection. This disruption to the training fleet is expected to persist throughout the evidence collection phase of the ATSB inquiry. Furthermore, the incident is likely to prompt General Aviation Maintenance Providers (MROs) to review their internal quality assurance processes. There is an expectation that CASA may issue safety bulletins reinforcing the mandatory requirement for dual independent inspections of flight control locking devices to prevent similar occurrences in the future.

Why This Matters

The incident at Griffith Airport serves as a stark reminder of the safety-critical nature of basic maintenance tasks. Because the failure of a single, small component can lead to a significant loss of flight control, the aviation industry maintains a zero-tolerance approach to omissions in assembly. This investigation will likely reinforce global best practices for maintenance verification, ensuring that secondary locking devices are not only installed but independently verified before an aircraft is returned to service.