comment_collisions: 29

This data as json

rowid id occurrence disposition tracking_number posted_date is_withdrawn title comment_text reason_withdrawn attachment_files content_files duplicate_comments source_slice
29 FAA-2007-28478-0052 1 union_alias 80384a2d 2007-09-24T04:00:00Z 0 James Zangger Background: Service letter issued April of 2007 to address corrosion issues identified in struts. Origin and history of suspect struts is undocumented. Maintenance practices associated with suspect aircraft are also undocumented. Intent was to prevent in flight failures of struts. AD Issuance: Timing of AD appears to have been prompted by an unrelated failure of a separate structure. History: Taylorcraft has no documented record of in flight structural failures until the recent Washington state fatality. (The accident aircraft was licensed in the experimental category, annual inspections had been performed and signed off by the owner IA, aircraft was stored outdoors on a lake in a salt air environment while on floats. Condensation would develop in locations in a float equipped airplane that may not apply to a land based aircraft.) Safety: Service letter was sufficient to inform owners of problem areas. (Distribution of the service letter was not consistent and did not reach all owners.) Maintenance: Annual inspections using normal maintenance practices have, over the years, found suspect areas. Appropriate repairs have been made to allow the continued safe flight of the aircraft. Inspection: Per the AD, the authorized inspections and frequency of such to determine the presence of corrosion are prohibitively expensive and unnecessarily repetitive. Recommendations: Allow Alternate Means of Compliance that have been approved on previous AD's of other aircraft - specifically, the Maule test allowed on Piper struts. This test would indicate whether the need for more extensive testing is required. A visual boroscope inspection would also identify any corrosion on the interior of the struts dictating the need for more extensive testing. While ultrasound inspections are able to accurately determine wall thickness, the eddy current inspection appears to be more appropriate on aluminum. An x-ray inspection would possibly be more revealing than either of these other methods and be the correct test for any future corrosion concerns in other areas. This would prevent the need for fabric removal in those areas. If a structure is determined to have no corrosion through the use of these test methods, the frequency of re-inspection bi-annually seems unnecessary. Logic would dictate that if no corrosion had occured in 60 years or more that little new corrosion would form in the next two years, certainly not enough to raise concern over the integrity of the material. Wouldn't it be reasonable to test a suspect strut to destruction as a means to determine if the strut meets the original design load criteria? This would allow a determination as to what would be acceptable levels of corrosion in a particular structure.         FAA-2007:2007-01-01:2007-12-31