The scheduled maintenance requirements for ex-military UH-1 series helicopters may not adequately address the increased risk of fatigue failures associated with repetitive heavy lifting operations that were not considered in the original design fatigue calculations.
Satisfied that AWB will inform at-risk operators and maintainers of identified safety issue.
On 5 July 2011, the Civil Aviation Safety Authority (CASA) published Airworthiness Bulletin 02 40 Issue 1 to:
...advise operators and maintainers to investigate the basis for and the correct implementation of the continuing airworthiness requirements of the applicable type certificate data sheet (TCDS) and incorporated supplemental type certificates (STC), particularly in regard to the retirement lives of all life-limited components.
The ATSB is satisfied that the action taken by CASA adequately addresses the safety issue.
