V-22 Dynamic Components Fatigue Design Usage Spectrum vs. Fleet History

A critical task for initiating an aircraft design is to determine how the fielded product will be used. For the V-22 Osprey, a usage spectrum was developed. The spectrum considered time spent in level flight, number of maneuvers per flight hour, type of maneuvers that would be flown, etc. With the V-22 fleet now exceeding 200,000 flight hours the actual usage spectrum can be compared to the design spectrum to gain key insights. The V-22 onboard recording system includes maneuver recognition software that permits this analysis. Results from fleet usage data are compared to the design usage spectrum to show areas where the original design spectrum is conservative and where it was not. The differences show how a usage-based appraisal of fatigue effects can be used for determining replacement intervals of life limited components.