F-5M DTA Program
doi: 10.5028/jatm.2009.0101113120

Daniel Ferreira V. Mattos*
Institute of Aeronautics and Space
São José dos Campos - Brazil
daniel.ferreira@iae.cta.br

Alberto W. S. Mello Junior
Institute of Aeronautics and Space
São José dos Campos - Brazil
amello@iae.cta.br

Fabrício N. Ribeiro
Institute of Aeronautics and Space
São José dos Campos - Brazil
fabricio@iae.cta.br

*author for correspondence

Abstract:

The Brazilian F-5 was submitted to avionics and weapons upgrade. This “new” aircraft has proven to be heavier and more capable. A comprehensive damage tolerance analysis is being performed to evaluate how the new mission profiles and weight distribution may affect the airframe structural integrity. Operational data were collected at the Brazilian Air Force Bases where the fighter is flown. Software was developed in order to acquire, filter and analyze flight data. This data was used for comparison between the pre and post modernization mission profiles and to determine the stress level in each of the known aircraft fatigue critical locations (FCL). The results show that the change in aircraft weight and balance and the new operational profile can significantly change the inspection intervals of certain fatigue critical locations of the structure. A preliminary result for the horizontal tail has shown that this component will have a much more restrictive maintenance schedule to assure flight safety.

Keywords:

Fatigue, Damage tolerance, Structure, F-5, Flight data analysis, Crack growth.