In the summer of 1967, a group of intelligence analysts gathered in the Defense Intelligence Agency's "Green Room," just outside of Washington, D.C., to puzzle over a strange spy satellite image. It showed a gigantic machine, something bigger than any known airplane, with wings that looked too short to fly, sitting in a fenced enclosure at Kaspisk, a small city by the Caspian Sea. "Jeez, that's a monster," said an Army colonel. "Yeah," said another, "the Loch Ness Monster." Someone added: "No, the Caspian. It's the Caspian Monster."
But what was it? How did it work? What did the Russians plan to do with it? The answers came slowly over the next decade: It was an ekranoplan, a new type of aircraft that exploited an aerodynamic phenomenon called ground effect to haul enormous payloads at high speeds over water. It was invented by Rostislav Alexeyev, a friend of Soviet Premier Nikita Krushchev. It was not yet working very well. And if the Amerikanski spies could think of a practical use for it, the Soviet military would have appreciated their advice, because Moscow politicians, keen to find a need for a project that owed its existence as much to connections as to any operational requirement, were hell-bent on ramming it down the armed services' throats.
After the Cold War ended, I asked a Russian aerospace engineer what he thought of the Monster and its descendants, which were being examined intensely by the Pentagon at the time. "A waste of money," he grumbled. "Every time it didn't work, (the designers told Moscow) it would work if it was bigger. And they got the money for it."
But they may have been on the right track. Today, engineers at Boeing are designing a cargo plane that, like the Caspian Monster, is designed to skim just above the water like a large sea bird. It's dubbed the Pelican, because it will use the same "wing-in-ground effect," or WIG, that the awkward bird does to glide almost effortlessly above the water. When applied to man-made flying vehicles, WIG aerodynamics represent a critical exception to a long-held rule of aviation-altitude equals efficiency. The reason most long-range airplanes are high-altitude jets is that flying in thick air at lower altitudes normally takes significantly more fuel. But if you get extremely close to the surface-around 50 feet or below, as a WIG vehicle would-a cushion of air generated by the plane's velocity helps support it in flight, so that the plane cruises even more efficiently than a high-altitude jet. The WIG aircraft Boeing is developing is bigger than the Caspian Monster: Its wingspan is about the width of the front of the Capitol. Boeing engineers are counting on the notion that enormous wings will provide more opportunity for the air below them to gently lift and propel the vehicle, allowing it to skate a mere 20 feet off the water at 300 mph.
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