COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY
SCHEDULE OF AIRWORTHINESS DIRECTIVES
Schweizer (Hughes) 269 Series Helicopters
AD/HU 269/93 Tail Rotor Blade Spar 7/88
Applicability: All 269 series helicopters equipped with P/N 269A6035-21 or P/N 269A6035-23 tail rotor blades having serial numbers as listed in the Requirement document.
Requirement: Action in accordance with Schweizer Service Information Notice No N-212. Compliance: Unless already accomplished, within the next 600 flight hours or prior to 31 March
1989 whichever occurs first.
Background: Recent x-ray inspections of the affected tail rotor blade spars have revealed corrosion pits that were not evident during the periodic visual inspections for corrosion, required by HMI Appendix B. The manufacturer has determined that the pitting was caused by corrosion which occurred prior to the cadmium plate process on the blade spar.