The concern sheet
Text extracted from the PDF.
Revised 1/24/02 Airworthiness Concern Sheet
Full Name Andrew McAnaul Title Aerospace Engineer Organization ASW-150 Department Aircraft Certification Office Address 10100 Reunion Place, Ste. 650 City State ZIP San Antonio, TX 78216 Telephone Number 210-308-3365 E-mail andrew.mcanaul@faa.gov Make, Model, Series, Serial No.:
Taylorcraft, All Models and Serial Numbers
Reason for Airworthiness Concern:
Corrosion/Cracking of the Wing Forward and Aft Lift Struts Date: 4/12/2007 FAA Description of Airworthiness Concern
Taylorcraft has issued Service Bulletin No. 2007-001 dated April 2, 2007 to inspect Taylorcraft left and right wing forward and aft lift struts for corrosion and/or cracks. The Service Bulletin is in response to independent lab inspection results of 12 different struts revealing moderate to severe corrosion that required strut replacement. These struts were picked out of a larger representative group in lift struts removed from several Taylorcraft airplanes. Failure of the lift strut may lead to in-flight wing separation of the wing and loss of controlled flight. Similar corrosion on Piper and Maule airplane wing lift struts, some involving cases of in-flight wing separations, resulted in the FAA issuing Airworthiness Directives AD 99-01-05 and AD 98-15-18 respectively. Taylorcraft Service Bulletin No. 2007-001 requires initial visual inspection of the lower 12 inches of the right and left wing forward and aft lift struts within the next 30 days, and eddy current or ultrasound inspection of the same lower 12 inch areas within the next 3 months, with recurring inspections every 24 months thereafter.
Replacement of the struts with an improved sealed strut is considered terminating action for the inspection requirements.
The FAA requests any information from aircraft owners, operators, or repair facilities regarding results of any lift strut inspections on Taylorcraft airplanes, especially where corrosion or cracks were found. Please include a description of the extent and location of any damage found and what type of inspection method was used. You may also propose Alternate Inspection/Repair Procedures, Cost Impact, Etc. (Note: Any comments or replies to the FAA need to be as specific as possible. Please provide specific examples to illustrate your comments/concerns).
A risk assessment accomplished in accordance with the Small Airplane Directorate Airworthiness Concern Process guide for the potential condition is attached. At this time, the FAA has not made a determination as to what type of additional corrective action (if any) should be taken. The resolution of this Airworthiness Concern could involve an AD action or SAIB, or the FAA could determine that no further action is needed at this time. The FAA’s final determination will depend in part on the information received in response to this ACS. The FAA endorses dissemination of this technical information to all owners/operators and requests association and type club comments.
Attachments: *SDR(s) *A/IDS *SL(s) *SAIB *FAASR/*NTSBSR *AD *AMOC *RA
Notification: FAA *AOPA *EAA Type Club *TC Holder Other: TFI
Response Requested __/__/__: Emergency (10 days) Alert (30 days) Information (90 days) (Space Bar Adds “X” to Check Boxes) *Service Difficulty Reports (SDRs); Accident/Incident Data System (A/IDS); Service Letter (SL); Special Airworthiness Information Bulletin (SAIB);
Federal Aviation Administration (FAA)/National Transportation Safety Board (NTSB) Safety Recommendation (FAASR/NTSBSR); Airworthiness Directive (AD); Alternate Method of Compliance (AMOC); Risk Assessment (RA); Aircraft Owners & Pilots Association (AOPA);
Experimental Aircraft Association (EAA); Type Certificate (TC)