AIRWORTHINESS DIRECTIVE
For the reasons set out in the background section, the CASA delegate whose signature appears below revokes Airworthiness Directive (AD) AD/CESSNA 206/48 Amdt 1 and issues the following AD under subregulation 39.1 (1) of CAR 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.
Cessna 206 Series Aeroplanes
AD/CESSNA 206/48
Amdt 2
Forward Door Post Bulkhead 3/2002
Applicability: All models that do not have Cessna Service Kit SK206-42 or SK206-42A or SK206- 42B or SK206-42C, as per Cessna SEB 93-5 Revision 1.
Requirement: 1. Visually inspect for cracks at the inside edge of the left hand and right hand bend relief notches of the forward door post bulkhead.
2. Visually inspect for loose or working fasteners securing the lower strut end pick- up fitting to the forward door post bulkhead. The inspection areas and typical crack location are shown in the diagram below.
Note 1: Inspection in accordance with Requirement 1 will initially require removal of certain floor panels. Incorporation of inspection holes in accordance with an approved modification will allow inspection of the relief notch without requiring removal of the floor panels.
Note 2: Inspection in accordance with Requirement 2 may be accomplished from outside the aircraft via the hole exposed by removing the lower wing strut fairing.
Note 3: Cessna Single Engine Service Bulletin SEB 93-5 refers.
Cessna 206 Series Aeroplanes
AD/CESSNA 206/48 Amdt 2 (continued)
Compliance: Inspect before exceeding 2000 hours aircraft time in service, before 100 hours time in service after 20 July 1995 or before 500 hours time in service since last inspected in accordance with this Directive, whichever occurs last. Thereafter inspect at intervals not to exceed 500 hours time in service.
Note: Unless a variation to the requirements of this AD has been approved, repaired or modified structure must continue to be inspected.
This amendment becomes effective on 31 March 2002.
Background: Numerous reports have been received of cracking in this area on Cessna models 206 and 182. The bend relief notch in the bulkhead serves as a stress concentration notch, causing fatigue cracks to propagate across the bulkhead web. The strut attachment area forms part of the wing’s primary load path, and loss of strength in this area could be catastrophic. Although most of this area is covered by the strut attach fitting and a bulkhead reinforcement doubler, the inside edge of the bulkhead, where the cracks have been initiating, is visible without removing the lower strut attachment fitting.
Amendment 2 of this Airworthiness Directive is issued to allow the installation of the appropriate Cessna Service Kit as terminating action for the repetitive inspection requirement.
Amendment 1 reduces the initial threshold time for inspection as several model 206 aircraft have been found cracked at less than 5000 hours.
Amendment 1of this Airworthiness Directive became effective on 20 July 1995.
The original issue of this Airworthiness Directive became effective on 27 April 1995.
David Alan Villiers
Delegate of the Civil Aviation Safety Authority 4 February 2002
The above AD is notified in the Commonwealth of Australia Gazette on 27 February 2002.