No. 11 is not just the fastest in the West.

The new Cray-2 No. 11 performing Star Wars calculations at the Air Force Space Technology Center's Weapons Laboratory here is the fastest supercomputer in the world."Until a faster gun comes along," said Sgt. Arthur Mangham of the lab's specially designed Computer Center at Kirtland Air Force Base, "it's the fastest of the fastest, which means it's even 17 percent faster than the other Cray-2s in existence."

Darragh Nagle, site analyst for Cray Research Inc., explained that No. 11 benefited from a memory improvement not available when its second-generation Cray-2 siblings were constructed.

It would short-circuit the Weapons Laboratory's comparably sluggish Cray-1 the first of the supercomputers by a factor of about 12, said Dr. N.L. Rapagnani, chief of the laboratory's communications-computer systems technology office.

But exactly how fast is the fastest?

"In layman's terms," Rapagnani said, "it would be the equivalent of having every person in Albuquerque have a personal computer, say 500,000 PCs, all tightly coupled together, working on the same problem with everyone hitting the enter key at the same exact moment. That's how powerful this machine is."

No. 11 went to work last fall and at its peak is expected to serve about 4,000 Air Force research and development users. Only about 100, however, can access the supercomputer at any one time, Rapagnani said.

Among No. 11's primary applications will be calculations and modeling of projects and problems for the Strategic Defense Initiative, known as Star Wars.

"Basically, it is to do large simulations of whatever we're building at the lab for the Air Force or SDI," said Rapagnani.

No. 11 has been program-tested at 1.952 billion operations per second, said William Snell, site manager for the Unisys Corporation at the laboratory.

"Mind-boggling," said Mangham.

When Snell thinks of No. 11 just three words come to mind: "small, fast and expensive." The stout, four-foot tall No. 11 cost $23 million and tips the scale at just under three tons. It occupies just 16 square feet of floor space.