Abstract: An HGA loader which utilizes sub-ambient air pressure to move a magnetic head of the HGA relative to a test surface. The HGA is mounted to a clamp and located adjacent to a nozzle. The nozzle draws in air through an orifice to create a sub-ambient pressure region below the suspension. Ambient air pressure will flow into the sub-ambient void created by the nozzle located below the suspension beam of tge HGA. The air flow will move the suspension beam away from the disk surface and unload the HGA. The level of the sub-ambient pressure and the separation between the head and disk can be varied by a computer controlled regulator valve. The loader can be used in a flying height tester where calibration is obtained by taking optical data while varying the flying height by changing the sub-ambient pressure. The sub-ambient pressure created by the orifice causes the HGA to bend about its natural pivot point or the bend radius of the suspension or load beam.