COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY
SCHEDULE OF AIRWORTHINESS DIRECTIVES
Beechcraft 76 (Duchess) Series Aeroplanes
AD/BEECH 76/18
Amdt 1
MLG “A” Frame Assembly 8/97
Applicability: Model 76 aircraft with serial numbers ME-1 through ME-437, that do not have both a part number (P/N) 105-810023-75 (left) and P/N 105-810023-76 (right) main landing gear (MLG) “A” frame assembly installed.
Requirement: Inspect, using both visual and dye penetrant methods, both the left and right MLG “A” frame assemblies for cracks in accordance with the Accomplishment Instructions section of Raytheon Mandatory Service Bulletin 2361 Revision III. Pay particular attention to the tips of the gussets and the small corrosion treatment hole adjacent to the gusset.
If any MLG “A” frame assembly is found cracked, replace the assembly with one of the following in accordance with Chapter 32 of the Raytheon Model 76 Maintenance Manual:
(a) A new MLG “A” frame assembly with the same P/N as that found cracked. The 100 hours’ time in service repetitive inspection requirement still applies when this design “A” frame is installed.
(b) A P/N 105-810023-75 (left) or P/N 105-810023-76 (right) MLG “A” frame assembly, as applicable. Repetitive inspections are no longer required on an MLG “A” frame assembly incorporating this design configuration.
Installing both P/N 105-810023-75 (left) and P/N 105-810023-76 (right) MLG “A” frame assemblies eliminates the repetitive inspection requirement of this directive.
Note: FAA AD 97-06-10 Amdt 39-9967 refers.
Compliance: Within 100 hours’ time in service after 17 July 1997, and thereafter at intervals not to exceed 100 hours’ time in service, until both P/N 105-810023-75 and P/N 105- 810023-76 MLG “A” frame assemblies are installed.
This airworthiness directive becomes effective on 17 July 1997.
Background: The FAA received reports of fatigue cracks developing on the main landing gear “A” frame assembly of Beech Model 76 aircraft. These cracks, if not detected and corrected, would cause the main landing gear to collapse.
Amendment 1 is issued in response to a new FAA AD which introduces terminating action for the repetitive inspection requirement of this directive if certain improved design “A” frame assemblies are installed.