Flying height, also referred to as floating height or head gap, is a crucial aspect of hard disk drives that determines the distance between the read/write head and the platter. The very first commercial hard disk drive, IBM 305 RAMAC, used forced air to maintain a 0.002-inch gap between the head and the platter, whereas the IBM 1301 was the first one with a hydrodynamic air-bearing slider that allowed the head and slider to float much closer to the disk surface.
Modern hard disk drives have a flight height of a few nanometers (around 5 nm), which means they can collide with objects as thin as a fingerprint or a smoke particle. However, hard drives are usually ventilated, with a filter in place that equalizes the air pressure inside the drive with that outside.
It’s essential to regulate the altitude of the hard disk drive as these devices float on a cushion of air and are not designed to operate in a vacuum. Future high-capacity hard disk drives are expected to be even more reliant on proper altitude regulation.
In open terrain, the recommended flying altitude is about 30 m for safety. Altitude is increased by the height of objects flown over, which means steep terrain, forests, and installations can limit high-resolution data collection. The signal-to-noise ratio affects vertical resolution, which can be improved with greater transmit torque and fast and accurate cutoff for TEM.
FAQs
- What is flying height?
Flying height refers to the distance between the read/write head and the platter in a hard disk drive.
- What is the flight height for modern hard disk drives?
Modern hard disk drives have a flight height of a few nanometers, making it possible for the head to collide with an object as thin as a fingerprint or smoke particle.
Conclusion
Flying height is a crucial aspect of hard disk drives that determines the distance between the read/write head and the platter. While modern hard disk drives have a flight height of a few nanometers, it’s essential to regulate altitude to avoid collisions and ensure proper device functioning. In data collection, the signal-to-noise ratio affects vertical resolution, and accurate cutoff for TEM and greater transmit torque can improve it.
