Design details and experimental and performance data are presented for 3 prototype orientedwedge, hydrodynamic, air-lubricated bearings with potential application to the spin axis of a gyroscope. The 3-wedge double-phase bearing performed satisfactorily under a 10-g radial load at 11,500 rpm, and a 4.8-g thrust load at 18,000 rpm for a 2-lb rotor. It had better stability characteristics under both load and no-load conditions than the 2-wedge bearing. T HE -WEDGE, DOUBLE-PHASE -DEGREE TAPERED-END BEARING PERFORMED SATISFACTORILY UNDER A -G RADIAL LOAD AT , RPM, BUT THRUST LOAD COULD NOT BE SUPPORTED BECAUSE OF MISALIGNMENT CONDITIONS OF THE TAPERED END COVERS FLAT THRUST ENDS APPEAR TO BE MORE PRACTICAL. The 2-wedge, inverted 60-degree bearing supported an 8-g thrust load at 18,000 rpm for a 2-lb rotor radial loading could not be accomplished because of radial instability. Bearings with rotor ld ratios of 1.0 or greater exhibit better radial operating performance than with small ld ratios. The internal temperature rise of both 2- and 3-wedge double-phase bearings was about 15 F at 20,000 rpm.