VERTICAL FORCE-DEFLECTION CHARACTERISTICS OF A PAIR OF 56-INCH-DIAMETER AIRCRAFT TIRES FROM STATIC AND DROP TESTS WITH AND WITHOUT PREROTATION

摘要

An investigation was made to obtain information on the vertical force-deflection characteristics of a pair of 56-inch-diameter type I (smooth contour) aircraft tires under three conditions:static tests, drop tests without prerotation, and drop tests with prerotation up to 470 revolutions per minute. The experimental results together with a few simplified theoretical considerations indicated that a small but notice-able difference between the tire vertical force-deflection characteristics existed for these three conditions and that there might be similar differ¬ences between these characteristics and those for realistic landing condi¬tions with finite horizontal velocity. Generally speaking, for increasing force, the tires are found to be least stiff for static tests, almost the same as for the static case for prerotation drop tests as long as the tires remain rotating, and appreciably stiffer for drop tests without prerotation.