That New Black Magic
In the early years of the cold war, enter Kelly Johnson and an clean sheet of paper--long enough to accommodate an 80-foot wingspan.
- By William E. Burrows
- Air & Space magazine, January 1999
(Page 4 of 4)
Baker, now a gentleman of considerable years, still spends most nights doing experiments in his basement laboratory in New Hampshire ("Don't call before 10 a.m.," he warns). He credits Walter Pierstorff, the general manager of the Schott Company in Mainz, West Germany, with supplying "excellent optical glass of many types." And, Baker adds, there were "no questions asked." The result was a lens that could pick out a basketball from over 13 miles in the sky. The master optician recalls "jousting" with Kelly Johnson over how much space the camera was going to have and how much it would weigh. Johnson allowed him about 500 pounds.
Baker does not seem as impressed with his creation as the rest of the world is. The B camera, he says, was simply an evolutionary development arising from other work that went back to World War II. He is too modest. The best the older cameras could achieve was 20- or 25-foot resolution at 33,000 feet. At more than twice that altitude, they would be useless, especially for intelligence purposes, in which photo interpretation required 10-foot resolution. Baker's challenge was to design a camera that would be four times better than anything ever built.
Baker also had to meet Kelly Johnson's weight limits, so he replaced a heavy and bulky prism used to scan to the left and right of the airplane's course with a single mirror mounted within a swiveling housing. The assembly followed an automatic sequence to capture overlapping images of a swath of ground that stretched from horizon to horizon.
For the pilots, the airplane was a handful to fly, uncomfortable for many hours, and although initially out of reach of Soviet weapons, that small luxury would not last long. To make it less visible, additional measures were tried. The first, and most obvious, was a flat, midnight-blue paint scheme to match the dark sky. It actually didn't blend all that well, but dark blue was better than polished aluminum, which had led to reports of lights in the sky over the Nevada desert where the U-2 was first tested. ("Pastels are the best stealth colors," Ben Rich once observed, "but real men don't fly pink jets.")
Another technique involved swathing the underside with a metallic grid called a Salisbury Screen, then covering it with black foam rubber to capture and dissipate radar microwaves. The third technique, tested in a program aptly named Dirty Bird, called for adding metal "standoff" posts from tail to nose and connecting them with wires set at precise distance from the skin. MIT's Lincoln Laboratory said the wires would cancel or scatter the radar energy reflected off the skin. Neither scheme worked, but the posts were especially disastrous. Some wires snapped during flight tests and lashed the aircraft like whips. More important, they cut the U-2's performance so badly that they nullified the reason for building it. "They went out and flew it," recalls Garfield Thomas, "and it was so draggy they would never get to altitude and never have any range." Rich said simply, "They made it look like a rake."
Even before the U-2's first missions, in June 1956, the CIA worried that its operational life over the Soviet Union would be no more than two years because of rapid improvements in Soviet air defenses. They were wrong; it would be nearly four years before Francis Gary Powers was downed. The airplane designated with a lowly "U" for "utility" to hide its true purpose would enter Air Force service in 1957, photograph Soviet missiles entering Cuba, and, in the hands of Nationalist Chinese pilots, penetrate the People's Republic of China. Today it flies frequent missions over Iraq in support of the United Nations' surveillance of that nation's efforts to produce weapons of mass destruction. But it was the knowledge that a U-2 would eventually get nailed that drove Kelly Johnson to invent its high-flying supersonic replacement.