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POSTFIX

It’s Stratovision

Spring 1994 | Volume 9 |  Issue 4

Ron Kaiser was in elementary school in 1948 when he played hooky to watch his first television program. His father had bought an eight-foot-high set with a twelve-inch screen for his small tavern in a western Pennsylvania coal-mining town, and Ron stayed home to watch the sixth game of the World Series from Boston. “There was so much snow in there it looked like a blizzard,” he said. “But you could make out the figures. You could see that there were really people inside that little machine.”

What made it even more marvelous was that the game was broadcast from an airplane, using an invention called Stratovision. Stratovision was the brainchild of Charles E. Nobles, a Westinghouse engineer. In December 1944, while flying over Texas, Nobles was struck by the similarities of radar and television. He saw the possibilities in transmitting television and FM radio from stratospheric airplanes. While ground transmitters were limited to about fifty miles, since they could only reach as far as the horizon, airplane transmission might cover more than two hundred.

Stratovision would also be cheaper than ground systems. Each airplane would cost an estimated thousand dollars per hour of operation, but ground systems could be some thirteen times as expensive. Even with a second plane flying nearby to ensure continuous service, the savings would be considerable.

By September 1946 engineers had a workable design. An airplane flying at 30,000 feet would relay signals originated on the ground. A fleet of fourteen planes, if deployed properly, could bring television to 78 percent of the country’s population, including many in isolated rural homes. The Glenn L. Martin Company offered a B-29 Superfortress with a pressurized cabin for testing.

Difficulty with financing delayed the Start of the experiment, but by 1948 Westinghouse had quietly begun flights over western Pennsylvania, rebroadcasting signals from Baltimore and Washington. The transmissions were identified as “airborne station X10A,” and anyone receiving the signals was asked to write to a box number in Baltimore. Responses poured in from such remote areas as Findlay, Ohio; Richmond, Virginia; and Port Huron, Michigan.

The next step was to use Stratovision as the transmitter for a regular station. On August 13, 1948, the company petitioned the Federal Communications Commission (FCC) for a permit to build a TV station in Pittsburgh that would broadcast from a transmitter flying some 30 miles west of the city at 25,000 feet, putting out 12.75 kilowatts. Such a transmission would cover 127,000 square miles and reach more than twelve million people.

Unfortunately, Westinghouse’s timing could not have been worse. In September the FCC imposed what would become a four-year freeze on new television permits in order to study the problem of signal interference between stations. Meanwhile, AT&T was developing a coaxial-cable system to connect the Atlantic seaboard with the Midwest; by 1950 it was in operation. What had looked so promising in 1945 ended five years later, when Westinghouse abandoned a system that seemed to be politically doomed by the freeze and fears of a Westinghouse monopoly.

In a sense, the launch of the communications satellite Telstar in 1962 fulfilled the Stratovision concept. In its original version it had already been revived the previous year with the Midwest Program on Airborne Television Instruction (MPATI), which broadcast lessons to public schools in Indiana and nearby states. The program was run by Purdue University and funded by the Ford Foundation; Westinghouse did the electronic work, led by Nobles himself. MPATI used two DC-Gs broadcasting over UHF channels 72 and 76. The program, always plagued by funding problems, was discontinued in 1968 when the FCC demanded a switch to a different frequency, which would have required new equipment. But several years before that happened, military representatives came by to learn how the system worked.

The military implemented Stratovision in Vietnam, after abandoning a plan to use it to reach Cuba. Beginning in February 1966, a Navy C-121 Super Constellation broadcast propaganda to the Saigon area, including news, parade footage, and even comedy skits. A second station broadcast from the same plane catered to American military personnel, showing Bob Hope, Ann-Margret, and the Grand Ole Opry, among others. Soon afterward the governments of South Vietnam and the United States agreed to build a four-station network, which began operation from temporary ground stations by fall, ending a final, brief, but successful use of a technology that never got the chance to find any commercial niche.

We hope you enjoyed this essay.

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