Patent ID: 7436620

Claim:
A method of selecting an electrical power to be applied to a subject head-based flying height actuator during operation of a disk drive having a subject disk and a subject head that includes a transducer and the subject head-based flying height actuator, the method comprising: detecting a touch-down power for each of a plurality of representative heads, each of the plurality of representative heads including a representative flying height actuator, wherein each of the plurality of representative heads is in intermittent contact with a representative disk when the touch-down power corresponding to that representative head is applied to the representative flying height actuator of that representative head; estimating a relationship between back-off power and touch-down power for the plurality of representative heads, wherein each of the plurality of representative heads has a specified transducer-disk spacing when the touch-down power detected for that representative head minus a back-off power determined for that representative head is applied to the representative flying height actuator of that representative head; detecting a touch-down power for the subject head; calculating a back-off power for the subject head using the estimated relationship and the detected touch-down power for the subject head; and selecting the electrical power to be applied to the subject head-based flying height actuator to be equal to the detected touch-down power for the subject head minus the calculated back-off power for the subject head.