Cessna 177 Stabilator Balance Weight Arm - Bracket

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AIRWORTHINESS BULLETIN Cessna 177 Stabilator Balance Weight Arm - Bracket AWB 27-014 Issue : 1 Date : 17 August 2012 Page 1 of 1 1. Applicability All Cessna 177 Series aeroplanes with aluminium stabilator balance weight arm brackets installed. 2. Purpose Alert operators and maintainers regarding cracking in the aluminium balance weight arm attachment brackets. Failure of the stabilator balance weight brackets could lead to loss of control. 3. Background CASA has received a defect report of cracking in all four of the aluminium stabilator balance weight attachment brackets. Cessna issued Single Engine Service Bulletin SEB 89-1 following reports of small cracks in the aluminium brackets in a limited number of aircraft owned by one operator in 1989. Apparently, reports of cracking increased following the issue of SEB 89-1, which identified the possibility of cracking at 2000 hours flight time since new. Cessna advanced SEB 89-1 to Revision 3, reducing the initial crack inspection threshold from 5000 hours to 2000 hours and maintaining the 200 hour/12 month inspection until replaced with stronger steel brackets which are listed in the SEB. 4. References Cessna Single Engine Service Bulletin SEB 89-1 Rev. 3 (Attached) 5. Recommendations CASA strongly recommends that Operators: 1. Determine if, where aluminium brackets are installed, that they are inspected in accordance with the requirements of SEB 89-1 Rev.3 (or later revision). 2. Consider replacing the aluminium stabilator balance weight brackets with steel brackets. 6. Enquiries Enquiries with regard to the content of this Airworthiness Bulletin should be made via the direct link e-mail address: AirworthinessBulletin@casa.gov.au or in writing, to: Airworthiness & Engineering Branch Civil Aviation Safety Authority GPO Box 2005, Canberra, ACT, 2601