Search Results

Aircraft weight and center of mass are two critical design and operational parameters that have to be within a design envelope to ensure a safe and efficient operation of aircraft. Previous efforts to accurately determine aircraft weight and center of mass before takeoff using landing gear shock strut pressures have failed due to the distortion of measured pressures by shock strut seal friction. Currently, aircraft loading process is controlled with loading sheets and passenger/cargo weight estimation as there are no online measurement systems that can accurately and efficiently estimate aircraft weight and determine the center of mass location before takeoff. However, errors in loading sheets, shifting cargo and errors in weight estimation could lead to incorrect loading of aircraft and, consequently, increase the risk of accidents, particularly in cargo flights.

This paper presents the additional evidence that the dynamic hydroplaning speed of H-type aircraft tires, running in deep water, is significantly lower than one determined by Horne’s equation. The factors such as tire footprint ratio, vertical load, and inflation pressure are analyzed to determine their magnitude on the hydroplaning speed. The full-scale, spin-down, test data are used to derive the boundaries of the expected hydroplaning speed. The recommendations are made emphasizing the areas of concern for a safe aircraft operation. The use of the standardized test procedure is proposed to expand the existing full-scale aircraft test results database.