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 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.: Air Tractor Models Air Tractor Model AT-400/400A/402/402A/402B serial numbers -0001 thru -1175 Air Tractor Model AT-502/502A/502B/503A serial numbers -0001 thru -2597 Air Tractor Model AT-602 serial numbers -0001 thru -1141 Air Tractor Model AT-802/802A serial numbers -0001 thru -0227 Reason for Airworthiness Concern:
Cracked Engine Mount Date: 11/06/2007 FAA Description of Airworthiness Concern (Who, What, Where, When, How? Attachments: RA and appropriate data)
The FAA issued AD 2007-13-17 to repetitively inspect Air Tractor AT-602 and AT-802/802A engine mounts for fatigue cracks following Snow Engineering Co. Service Letter #253. The manufacturer has since revised Service Letter #253 to inspect certain serial number AT- 400 and AT-500 series airplanes for cracked engine mounts. The revised Service Letter is in response to finding an AT-502B with a badly cracked lower engine mount tube where it is welded to the engine mount ring. The Service Letter requires repetitive visual inspections and now includes installation of welded gussets for all Air Tractor models as a terminating action for the inspections. The manufacturer has incorporated the gussets in new production airplanes. Owners are to contact the factory for repair assistance if a crack is found.
The FAA requests any information from aircraft owners, operators, or repair facilities for any inspections performed on Air Tractor engine mounts where cracks were found. Please include any information about crack location(s), crack size(s) and how it was repaired. 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).
The resolution of this airworthiness concern could involve 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 clubs comments.
Attachments: *SDR(s) *A/IDS *SL(s) *SAIB *FAASR/*NTSBSR *AD *AMOC *RA
Notification: FAA *AOPA *EAA Type Club *TC Holder Other: NAAA
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)