An event that indicates unexpected shutdown of a hard disk drive is determined. The hard disk includes first and second controllers that control respective first and second independently-operable actuators. Each of the actuators has one or more heads that access one or more spinning disks of the hard disk drive. While receiving power for the hard disk drive via back-electromotive force of a motor driven by the one or more spinning disks in response to the event, the first and second controllers independently move the respective first and second actuators to safe positions. In response to determining the first and second actuators are in safe positions, write cache data associated with the first and second controllers is written to a non-volatile memory.