Spin Doctors- page 2 | Space | Air & Space Magazine
The Navy’s 85-foot-tall antenna at Point Mugu, California, relayed signals from the Syncom 3 satellite until 1966. (Boeing)

Spin Doctors

For that satellite dish on your roof and the phone calls you make to Japan, you can thank Harold Rosen.

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The team set to work at Hughes’ Lincoln Avenue campus in Culver City, a few miles from Los Angeles International Airport. They designed the system during normal work hours. No extra money was needed just yet. To get a payload into geosynchronous orbit, the rockets of 1959 would need two extra stages: one to lift the satellite from low altitude up to 22,000 miles, and another to make the resulting elliptical orbit circular. The rocketry was tricky, but Rosen, who had earlier worked on guided missiles at Raytheon, believed it could be done as long as the weight of the spacecraft was kept to a minimum.

The satellite would use a “traveling-wave tube” to amplify incoming radio waves for retransmission (see “How to Pump a Signal,” opposite). Developed by Kompfner and subsequently refined at Bell Labs by Kompfner and Pierce, the tube used a cathode to fire a beam of electrons through a coiled wire surrounded by a magnetic field. Incoming radio signals were transmitted through the coil and, as they interacted with the electrons, were amplified before being beamed back to Earth. Even in today’s satellite communications, traveling-wave tubes are a mainstay.

Hughes’ expert in traveling-wave tubes was John Mendel, a transplant from Bell Labs. He had developed a way to shrink the size of the tube’s magnets, thereby making the device a better fit for aircraft, and especially for spacecraft, where every ounce counted. Rosen told Mendel he needed a traveling-wave tube that was no more than a foot long and weighed no more than a pound. Mendel delivered it.

The most challenging task was to build the attitude- and orbit-control system. Satellites tend to drift away from a desired orbit and need small thrusters for station-keeping. To work properly, a geosynchronous satellite needed to be stabilized in orbit so the communications beam they shined on Earth would be consistent.

The most effective way to stabilize spacecraft in 1959 was with large, spinning reaction wheels, but they weighed a lot and tended to wear out. Rosen, however, had an inspiration. He remembered from his days at graduate school that rotational forces could exert a powerful stabilizing effect on a projectile, such as a bullet or a football. If a satellite were spinning on an axis parallel to Earth’s, station-keeping could be handled by a single thruster. First, however, the satellite, traveling like a tight spiral during launch, would have to be tipped over once it got into orbit so the spin axis would be parallel to Earth’s. Rosen figured he would need four additional thrusters on the satellite to accomplish this. He showed the idea to Williams.

“The basic concept was mine,” Rosen says. “But I didn’t do the math.” Williams did. He showed that by using fast-acting pneumatic valves and short bursts of compressed nitrogen, the satellite could be maneuvered into position with only one thruster. This made construction vastly simpler. Then Williams designed a sensor that could determine the angle between the satellite’s spin axis and the sun. By combining this measurement with information from the satellite’s signal, controllers could determine the spacecraft’s spin axis attitude. Carefully timed pulses from the thruster would then keep the satellite flying in the correct attitude. (This technology would lead to one of the longest patent lawsuits in U.S. history—the “Williams case”—which Hughes filed against the U.S. government in 1973. Hughes claimed the government had used the company’s patented technology on a number of space programs, including the Department of Defense’s Global Positioning System and NASA’s Galileo probe to Jupiter. The government argued that Hughes had exaggerated the importance of the technology and should not have been granted a patent in the first place. In 1999, a federal judge agreed with Hughes, ordering the government to pay $154 million for patent infringement.)

By the end of 1959, the team had a working design. Rosen and Williams presented it to Hughes general manager Lawrence “Pat” Hyland. In an interview with author Helen Gavaghan for her 1998 book Something New Under the Sun: Satellites and the Beginning of the Space Age, Hyland, who died in 1992, described listening to two young engineers with a costly, “hare-brained scheme.” While it sounded plausible, Hyland didn’t want to take the risk. Rosen wanted to launch from a Pacific island on the equator, and Hyland objected: The island was owned by the British, he said, and there was no launch infrastructure. It couldn’t be done. And that was the verdict, at least at first. Management urged the team to seek funding partners, especially the government. Rosen and his team presented their plan to GTE, Bell Labs, the U.S. Army Signal Corps, and the new space agency, NASA. There were no takers.

From the beginning, Rosen said he believed the design offered no technical showstoppers, but others weren’t so sure. Mendel, now retired in northern California, recalls that in 1960 a geosynchronous satellite “was anything but a slam dunk.” The reason: money. “The whole key to this experiment was economics,” he says. “It costs $30 million or $40 million for the launch vehicle, and you have to get the satellite on station and leave it there for years. If you can’t do that, there’s no way to do this and make money.” Rosen’s bluntness and lack of interest in a gradual development plan were not helping matters. “He wanted to go for the whole thing,” Mendel says. “He made some people upset, especially in the government.”

But Rosen’s team had faith in him, and Rosen in them. Hudspeth, Mendel recalls, was “a great nuts-and-bolts guy,” and Williams “was a genius. Nobody else in the country knew how to do what he was doing.” At one point in 1960, the team members decided to kick in $10,000 apiece of their own money and start their own business.

Rosen took the plan to his old bosses at Raytheon, who were interested. But Raytheon wanted to build the satellite without partners, and insisted that Rosen’s team quit Hughes and move to Massachusetts. The Californians weren’t anxious to relocate and Hyland didn’t want to lose them. Williams told Hyland about the team’s self-financing plan and plunked down a $10,000 check to show he was serious. At that point, Hyland finally agreed to fund a prototype.

About Guy Gugliotta

Guy Gugliotta, a former national reporter for the Washington Post, is a freelance science writer based in New York.

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