Spectrum Editing for a Full-Scale Fatigue Test of a Fighter Aircraft Wing with Buffet Loading
SourceThis paper describes the spectrum editing techniques that were used to derive the test spectrum for the full-scale fatigue test of an F/A-18 wing that is currently underway at the Institute for Aerospace Research, National Research Council Canada. The derivation of the baseline spectrum and the truncation methodology are described, together with details of the validation process and the calculated effects of the truncation levels that were accepted.
Even with aggressive truncation, the test spectrum contained nearly 135 000 unique load conditions. Because of control system limitations and the time required to optimize and check the actuator loads for so many load conditions, a binning process was used to reduce the number of unique load conditions to less than 50 000. The process is detailed and the effects on the calculated life are discussed.