27-023 - Schweizer/Hughes 269C Helicopters - Cracked Main Rotor Longitudinal Pitch Mixer Bellcrank

ATA Chapter: 27

Subject:

The CAA has received a report of an operator finding a cracked main rotor longitudinal pitch mixer bellcrank P/N 269A7519 on a Hughes 269C helicopter. A subsequent inspection by an engineer could not identify any indication of damage, or corrosion which may have initiated the crack. Operators are advised to pay particular attention to the flight control linkages when carrying out pre-flight inspections as required by the Pilot’s Flight Manual. Maintenance providers should thoroughly investigate any defects found during the scheduled inspection of helicopter flight control system/linkages.

Applicability:

All Schweizer/Hughes 269C Helicopters – Cracked Main Rotor Longitudinal Pitch Mixer Bellcrank.

Purpose:

The CAA has received a report of an operator finding a cracked main rotor longitudinal pitch mixer bellcrank P/N 269A7519 on a Hughes 269C helicopter (For the location of the affected P/N refer to: IPC 4-16-18 and Figure 1 in the CAN).

Background:

During a daily pre-flight inspection of the aircraft the pilot noticed a crack in the longitudinal pitch mixer bellcrank.

A subsequent inspection by an engineer could not identify any indication of damage, or corrosion which may have initiated the crack.

The affected aircraft had 18436 hours TTIS. However, it is not clear if the defective bellcrank had been installed since new.

Recommendation:

Operators are advised to pay particular attention to the flight control linkages when carrying out pre-flight inspections as required by the Pilot’s Flight Manual.

Maintenance providers should thoroughly investigate any defects found during the scheduled inspection of helicopter flight control system/linkages.