In a disk drive, when an off-track error occurs during a sequential disk access operation that spans multiple contiguous data tracks, efficient recovery is performed. In an embodiment, the disk access operation (e.g., reading from or writing to a disk) is attempted for all sectors of the sequential disk access operation. The disk access operation is then attempted again for sectors associated with any off-track errors that occurred during the disk access operation. In another embodiment, when an off-track error occurs during a sequential write operation in a shingled magnetic recording drive, the data originally targeted to be written to a first portion is written to a second portion of the data track that follows the first portion. Since no additional revolutions of the disk are needed for data associated with the sequential write operation to be written to the disk.

According to one embodiment, a magnetic disk device includes a first magnetic disk, a second magnetic disk, a first actuator with a first head which reads/writes data from/to the first magnetic disk, a second actuator with a second head which reads/writes data from/to the second magnetic disk, the second actuator operated independently from the first actuator, a first controller configured to retracts the first actuator at a first time, and a second controller configured to retract the second actuator at a second time which is shifted from the first time by a certain period of time.

According to one embodiment, a magnetic disk device includes a first magnetic disk, a second magnetic disk, a first actuator with a first head which reads/writes data from/to the first magnetic disk, a second actuator with a second head which reads/writes data from/to the second magnetic disk, the second actuator operated independently from the first actuator, a first controller configured to retracts the first actuator at a first time, and a second controller configured to retract the second actuator at a second time which is shifted from the first time by a certain period of time.

A data storage device is disclosed comprising a head actuated over a disk comprising servo data for defining a plurality of data tracks, including consecutive data tracks N1, N, and N+1. Data is written to data track N using a position error signal (PES) generated by reading the servo data, and a read track trajectory for data track N is generated based on the PES of the write. Data is read from data track N based on the read track trajectory for data track N.

According to one embodiment, a method includes running a magnetic recording tape over an edge of a tape bearing surface of a module, where the edge is proximate to a sensor of the module, detecting magnetic fields from the magnetic recording tape at different wrap angles, and selecting one of the wrap angles of the magnetic recording tape to provide about a predefined height of tenting of the magnetic recording tape above the sensor.

A data storage device is disclosed comprising a head actuated over a disk, wherein the head comprises a write assist element. Data is written to the disk using the write assist element. A protrusion of the head toward the disk is measured periodically, and an abnormality with the write assist element is detected when a slope of the protrusion measurements indicates the protrusion is increasing.

A data storage device is disclosed comprising a head actuated over a disk, wherein the head comprises a write assist element. Data is written to the disk using the write assist element. A protrusion of the head toward the disk is measured periodically, and an abnormality with the write assist element is detected when a slope of the protrusion measurements indicates the protrusion is increasing.

An apparatus, according to one embodiment, includes a substrate and a closure above the substrate. A gap is positioned between the closure and the substrate, the gap having an array of magnetic transducers extending therealong and unpatterned films. The gap further includes a first layer of a first material having a bulk modulus of elasticity lower than the unpatterned films in the gap. An apparatus according to another embodiment includes a plurality of magnetic transducers arranged in a linear array, and a layer of an expansion material between each adjacent pair of magnetic transducers in the array. An encapsulant is positioned between each layer of the expansion material and the adjacent magnetic transducers. The expansion material has a greater coefficient of thermal expansion than the encapsulant.

An apparatus includes a module having a tape bearing surface, a first edge, and a second edge, where a first tape tenting region of the tape bearing surface extends from the first edge along the tape bearing surface toward the second edge. A guide is positioned relative to the first edge for inducing tenting of a moving magnetic recording tape and to create a point of inflection of the moving magnetic recording tape at a location above the tape bearing surface that is about midway between a peak of the tenting and a point of closest approach of the moving magnetic recording tape to the tape bearing surface. A sensor is located in a thin film region of the module. The sensor has a free layer. The location of the point of inflection of the moving magnetic recording tape is between the free layer and the second edge.

According to one embodiment, a magnetic disk device includes an actuator assembly including an actuator block including a rotatable bearing unit, a plurality of heads movably supported by the actuator assembly, a first sensor provided to the actuator block, and a second sensor provided at a position different from the first sensor.