final book al hoagland - Archive Server - Computer History Museum

CHAPTER 6
Importance of Magnetic Disk Technology Recognized
The late 1970s and early 1980s were a period of great turmoil for magnetic disk data
storage. Three major events were to have a major impact on its future. The first event was
the failure of IBM to ship the IBM 3380 disk drive on schedule, the first time a shipment
date had been missed (delayed from June 1980 to October 1981). The 3380s were the
most advanced disk drives the company had yet developed and had the largest market
demand ever for such a product. The second event was the growing realization that
magnetic bubbles did not appear able to replace magnetic disk storage in the
memory/storage hierarchy. The third event of importance was the emergence of a
“personal” computer market with the Apple II in 1977 and the IBM PC in August of
1981.
The delay in production of the IBM 3380 was due to the problem of intermittent contacts
between heads and disks. A head hitting the disk leads to both head and disk damage and
loss of data. This made it very clear within IBM that research on magnetic disk
technology had not been adequate to support the product development activities
necessary for successive generations of advanced disk drives. The growing complexity
and technical sophistication of magnetic disk drives had not been sufficiently appreciated
or understood for several years. The 3380 program was in desperate need of more human
resources with skills and expertise in magnetics, materials, instrumentation and testing to
help “troubleshoot” the causes of failure. San Jose had only a few people in research and
product development exploring technical advances, and these were divided between the
separate Research and Development organizations. However, an untapped pool of talent
with magnetics skills already existed in the magnetic bubble program within the Research
Division.
Magnetic bubble technology was proving to be much more expensive than disks and was
also not as fast or cost competitive with semiconductor memory. With the necessity to
quickly address and solve the problems of the 3380, the Research magnetic bubble group
and advanced magnetic recording resources in both the Research and the General
Products Division (which was responsible for the 3380 product) were assigned to support
the 3380 program. A re-organization combined the magnetic bubble group with the
existing advanced recording groups into a new Magnetic Recording Institute. Magnetic
disk storage had gone from being viewed as a technology near the end of its life to the
main hope for the future of storage.
The third but somewhat independent factor at the time was the emergence of what is now
called the PC or personal computer. Hobbyists and small companies were making
hardware that suddenly provided electronic computer capabilities for individual use. This
development was stimulating great interest and many new projects were undertaken to
address this new need. Existing technology was more than adequate to design and make
low-cost drives that only required small data capacities and small companies quickly
entered this marketplace.
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