Document ID: chunk:federal_register_of_legislation:F2006L01058:body:0:p2
Version: federal_register_of_legislation:F2006L01058
Segment Type: other
Provision Reference: 
Character Range: 2949–4186

fatigue cracking.  The effectiveness of this modification in preventing cracking has been proven over 25 years, with no reports of cracking in any aircraft that has the modification per DoA (now CASA) approved SuperAir Engineering Order # S46 Issue 1.

             Amendment 1, effective 20 March 2003, was issued to make a distinction between aircraft engaged in agricultural operations and aircraft engaged in non-agricultural operations.  It has been shown that fatigue in the flap control torque tube is a function of the number of flight cycles (i.e. flap deployments).  Aircraft engaged in agricultural operations are generally subjected to an order of magnitude more cycles than non-agricultural operations, causing accelerated fatigue of the flap control torque tube.  This amendment allows aircraft engaged predominantly in non-agricultural operations to inspect the torque tube at 220 hourly intervals rather than 100 hourly intervals as specified in the original issue of this AD.  The inspection procedure remained unchanged from the previous issue of this AD.

             The original issue of this AD became effective on 01 August, 1977.

David Villiers
Delegate of the Civil Aviation Safety Authority

29 March 2006