Document ID: chunk:federal_register_of_legislation:F2009L02830:body:0:p3
Version: federal_register_of_legislation:F2009L02830
Segment Type: other
Provision Reference: 
Character Range: 5717–7129

Repetitively thereafter at intervals no to exceed 100 hours time in service.
             This Amendment becomes effective on 30 July 2009.
Background:  Since the issue of FAA AD 2007-13-17, which affected Models AT-602, AT-802, and AT-802A aircraft, Air Tractor received a report of a Model AT-502B aircraft with a crack located where the lower engine mount tube is welded to the engine mount ring.  In addition, Air Tractor developed gussets that, when installed in accordance with certain service letters, terminates the repetitive inspection requirement.  Consequently, new FAA AD 2008-10-12 establishes new inspection actions for the AT-400 and AT-500 series aircraft and incorporates a mandatory terminating action for the repetitive inspections.  The actions required by this Directive are intended to detect and correct cracks in the engine mount, which could result in failure of the engine mount and possible separation of the engine from the aircraft.

             Amendment 1 is issued in response to a new FAA AD, which was prompted by a report of a Model AT-602 aircraft with a crack completely through the gusset that was installed as required in FAA AD 2008-10-12.  Consequently, this Directive requires repetitive inspections of engine mounts of all previously affected aircraft with or without gussets installed.

David Villiers
Delegate of the Civil Aviation Safety Authority

18 June 2009