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Even the wing tips and the midwing "super pods," which look like fuel tanks, are crammed with sensors and electronics. Its paint scheme makes it look stealthy, but a U-2 is detectable by radar. (Denny Lombard/Lockheed Martin)

The U-Deuce

The secret to a spyplane's eternal youth is a new set of gadgets installed on a classic chassis.

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(Continued from page 1)

AKAs: The Dragon Lady’s Aliases
There is no structural difference between the U-2R and the TR-1, and the two designations are confusing. The U-2R, which first flew in 1967, was a strategic intelligence collector capable of very long flights. The Strategic Air Command used it to locate Soviet uranium enrichment plants, air bases, and naval bases, monitor a French nuclear test in the South Pacific, sniff the air for trace gases from nuclear weapons, and photograph the Israeli reactor at Dimona.

If NATO and Warsaw Pact armies had slugged it out, the aircraft would have been controlled by army commanders. They would have used it to find enemy forces behind the front lines and report on their numbers, their armament, and their location. That mission would have been tactical; hence the “TR” in TR-1 stood for tactical reconnaissance. As it was, TR-1s flew missions along the Iron Curtain until the cold war ended. But the strategic and tactical versions were essentially the same airplane.

Making a distinction in designations also had a political purpose. After the downing of Powers and the revelation of the Central Intelligence Agency’s overflights, the United Kingdom and West Germany felt allowing U.S. spyplanes to operate from their territory was embarrassing—or awkward, as the British would have put it. The United States flew regular reconnaissance missions in four-engine RC-135s around the periphery of the Soviet Union, but those aircraft looked like innocuous transports. U-2s, on the other hand, looked the part. Changing the Dragon Lady’s designation to TR-1 accommodated our allies’ sensitivities. Eventually, juggling two separate sets of manuals and maintenance records that were essentially identical became a burden, and there was funding confusion, so in 1992, with the cold war at an end, the TR-1s were quietly rechristened U–2Rs, and the TR-1 was history.

The latest reincarnation of the Dragon Lady is the U-2S, which the Air Force began operating last October. There are 32 of them, along with five two-seat training versions, designated U-2ST. The U-2S is the airplane Swords most likes to talk about. He says that over the last decade, more than $1.7 billion has been spent to turn it into a new aircraft. The U-2R’s Pratt & Whitney J75-13B engine, for example, was replaced by a General Electric F118-GE-101. The newer engine is 30 percent lighter, 39 inches shorter, more fuel efficient, and much easier to maintain, needing an overhaul every 2,500 hours instead of every 800. Swords says that only 10 percent of the engine was redesigned specifically for the U-2S. The rest is the same as the engines used in the F-16. With the new engine, the S gained 1,220 nautical miles of range and about 3,000 feet of altitude.

Maximum altitude is a sensitive subject. Lockheed Martin and the Air Force refuse to discuss the U-2S’s service ceiling; official statements will only say that it is “above” 70,000 feet. One Internet site has incorrectly stated that it can reach 90,000 feet. Based on its dimensions, an aerospace engineer friend of mine once calculated that it could reach 75,000 feet with full fuel, 78,000 toward the end of a mission.

The new engines, which converted R models into S models, are only a small part of a continuing modernization process that is still driven by the sensors. The ground technicians can mount different noses, which are interchangeable the way lenses on a camera are, so one kind of imaging system can quickly be substituted for another: optical for radar, for example. Other sensors, avionics, and navigation equipment are carried in a number of places: in the E-bay in the airplane’s upper fuselage, in a larger, fuselage-wide Q-bay behind the pilot that carries cameras pointing downward, in large wing “super pods” that hold signals intelligence equipment, and at the wing tips. A special teardrop-shape pod that sprouts from the upper fuselage, sometimes erroneously thought to be radar, houses an antenna that transmits data via satellite relay.

Wired Eyes
The new intelligence collecting devices are not only extraordinarily sensitive, they also interact with one another like components of a nervous system. The sensors either look or listen, and three of them collect imagery:

An ASARS-2A (for Advanced Synthetic Aperture Radar System) is nose-mounted for all-weather and day-night capability. It can observe 100,000 square miles of Earth’s surface in an hour with a resolution of one foot. The radar has a moving-target indicator that can highlight a column of advancing tanks, for example. The 2A is the latest version of the ASARS and is just going into operation.

An electro-optical system called SYERS 2 (Senior Year Electro-optical Reconnaissance System) uses five visual and two infrared bands that can combine to penetrate haze or darkness. It too is nose-mounted and continually upgraded to improve collection at night and bad weather. The infrared system is so sensitive it can detect the temperature difference between the cooler fuel in an airplane’s tanks and the warm airframe and show the amount of fuel on board.

A wet film system, called an Optical Bar Camera, that was initially developed for the Lockheed SR-71 Blackbird has been converted by Goodrich to be carried in the U-2S’s Q-bay. Its 66-inch focal length produces very-high-resolution photographs straight down and at angles to the sides of the airplane. Though it still uses film, the camera has been improved. And although the images on the film can’t be transmitted until the film is developed after the airplane lands, wet film produces photographs that are clearer than digital images.

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