Head spacing verification in magnetic disk drive systems during end-user operation

Magnetic disk drive systems and associated methods are described for verifying a spacing between read/write heads on a slider and a magnetic recording disk during end-user operation. An operating power applied to heating elements in the slider controls the spacing due to thermal protrusion. While in end-user operation, the operating power is temporarily increased to a test power to decrease the spacing. The test power is then evaluated to determine if contact between the read/write heads and the magnetic recording disk is detected. If contact is not detected, then the spacing due to the operating power is determined to be adequate. If contact is detected, then the operating power is recalibrated.