AD/BEECH 55/62 Amdt 6 - Wing Main Spar Centre Section (Cth)

AIRWORTHINESS DIRECTIVE On the effective date specified below, and for the reasons set out in the background section, the CASA delegate whose signature appears below revokes Airworthiness Directive (AD) AD/BEECH 55/62 Amdt 5 and issues the following AD under subregulation 39.001(1) of CASR 1998. The AD requires that the action set out in the requirement section (being action that the delegate considers necessary to correct the unsafe condition) be taken in relation to the aircraft or aeronautical product mentioned in the applicability section: (a) in the circumstances mentioned in the requirement section; and (b) in accordance with the instructions set out in the requirement section; and (c) at the time mentioned in the compliance section.

Beechcraft 55, 58 and 95-55 (Baron) Series Aeroplanes AD/BEECH 55/62 Amdt 6 Wing Main Spar Centre Section 13/2008

Applicability: As detailed in the requirements document. Requirement: Inspect the wing forward spar carry through structure forward and aft frames, in accordance with Beechcraft Service Bulletin No 2269 Rev 1, dated March 1990 or later FAA approved revision.

Note: FAA AD 90-08-14 Amendment 39-6563 refers. Compliance: Within 100 hours time in service after 30 November 1989, or prior to the accumulation of 1500 hours total time in service, whichever occurs later. Where no cracks are found, repeat the inspections at intervals not to exceed 500 hours time in service. Where cracks are found, repeat the inspections at intervals as detailed in the Requirement Document. Crack limits must not be exceeded.

Specific locations repaired or reinforced by the installation of the applicable Beech P/N 58-4008 kit or other approved scheme, need not be inspected before 1500 hours time in service after installation of the repair, however affected areas adjacent to repair doublers remain subject to the above compliance. Aircraft inspected in accordance with the previous issue of this Directive, shall be considered to have been inspected in accordance with this amendment. This Amendment becomes effective on 18 December 2008. Background: There have been numerous reports of cracking at various locations in the wing carry through structure. This problem was first found in Australia in 1981. The cracking is caused by fatigue in the corners of the fuselage frame webs around and between huckbolts and in area where stringers are attached. To date there have been no reports of cracks having progressed to failure, but uncorrected this condition could lead to eventual catastrophic failure.