Study of CL-415 usage in forest service operation

Abstract

Results of analyzing airframe usage from a fleet of four CL-415 Super Scooper aircraft flown in support of the United States Forest Service aerial firefighting operations are reported. Data used for this report was collected over the calendar years 2015-2019 and consisted of approximately 4,700 hours of flight time. Firefighting missions have been divided into ten flight phases. Airframe usage has been examined for each flight and each phase of the flight. The results have been compared with aircraft limitations on airspeeds, altitudes, and load factors. Some incidents of excessive vertical acceleration and indicated airspeeds, for the corresponding flap deflection, are shown to have occurred. The largest and most frequent vertical load factors are shown to be associated with drop phases. Lack of clear indicators, such as weight on wheels, for water landings have prevented clear identification of points of contact with, and departure from, water. This has led to inclusion of water impact loads in the related V-n diagrams, which have been shown to be of significance.