A disk drive that contains a fly on demand head (FOD) and a process for determining contact between the FOD head and a disk. The head includes a heating coil that can receive various levels of power. The process may include a routine to determine head position estimate error data. Variance values for the estimate error data are generated for different power values and used to determine a contact point between the head and the disk. The process may also collect a plurality of signal amplification gain control (SAGC) signal values and compute an average of the SAGC values. Average SAGC values for different power levels can be generated and used to determine a contact point between the head and the disk.