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[Abstract] This paper discusses factors influencing airplane retirements. An airplane life cycle model is introduced to describe the fleet dynamics, and retirements are defined as airplanes permanently withdrawn from service which consist primarily of airplanes being scrapped. Contrary to the fluctuating parked fleet, airplanes retired per year as a percentage of fleet exhibited a steady evolution, averaging at 1.6% for single-aisles and 1.9% for twin-aisles since 2000. The retirement age of passenger airplanes in the past five years averaged at 28 for single-aisle and 25 for twin-aisle airplanes respectively, and did not vary significantly across regions. Single-aisle passenger airplanes are parked for about two years throughout their life cycles while freighters and twin-aisle airplanes have longer parking periods. Freighters are retired at older ages than passenger airplanes; however, cumulative flight hours of retired single-aisle freighters and passenger airplanes are nearly equivalent. Airplanes’ life has been extended as technology advances. Survival curves of the Boeing 707 and 727, DC8, and DC9 types describe the retirement profile of individual models. Results verified the impacts of technology, airplane usage, and major modifications on 50 percentile retirement age. Results further suggested that an age threshold for retirement by model exists and that airplane retirements are accelerated when that threshold is passed. |
