NASA-TN-3604

Abstract

The low-speed (up to 2 miles per hour) cornering characteristics of two 26 X 6.6, type VII, 13-ply-rating tires under straight-yawed rolling were determined over a range of inflation pressures and yaw angles for two vertical loads, one load approximately equal to the rated vertical load and the other load approximately equal to the rated vertical load and the other load approximately equal to twice the rated vertical load for these tires. The cornering characteristics of one tire rolling along circular paths of different radii were investigated for one condition of vertical load and inflation pressure. Static tests were also performed to determine the vertical, lateral, torsional, and fore-and aft elastic characteristics of the tires. Several vibration tests were also performed to determine the dynamic lateral elastic characteristics of the tires. The quantities measured included lateral or cornering force, drag force, torsional moment or self-alining torque, pneumatic caster, vertical tire deflection, lateral tire deflection, wheel torsion or yaw angle, rolling radius, and relaxation length. Some supplementary tests which included measurements of tire footprint area and the variation of unloaded tire radius with inflation pressure were made.