ABSTRACT
This paper describes the approach for the fatigue evaluation of Aero Ae 45 S aircraft (registration OK-KGB). An analysis was carried out to define the individual fatigue life of this airplane based on its service history. By applying a newly developed flight loading spectrum and airframe full-scale fatigue test results, the original safe-life limit was proposed to be extended from 3000 to 4600 flight hours, which was approved by CAA. The limit extension was supported by eddy current and penetrant inspection programs for the primary fatigue critical area of the lower wing main spar attachment lugs made of L-ROL steel. Inspection intervals were determined using damage tolerance analysis techniques, fracture mechanics, and fatigue crack growth code NASGRO.
