The secret to a spyplane's eternal youth is a new suite of gadgets installed on a classic chassis.
- By William E. Burrows
- Air & Space magazine, March 2005
Denny Lombard/Lockheed Martin
(Page 2 of 6)
The U-2’s adaptability has spurred the creative drive of two generations of engineers. Although Johnson conceived the CL-282 to look and listen, successive versions have been put to other uses, at least experimentally, a flexibility that undoubtedly pleased him. (He died in 1990.) Two were fitted with air samplers to monitor nuclear tests. Ten were given inflight refueling capability (no longer used). Someone even proposed modifying a U-2 into a bomber, with tricycle landing gear, but the idea didn’t fly. Three got folding outer wings for use on carriers. All U-2s now have wings that fold 70 inches from their tips to help get them into small hangars overseas.
Two changes were of fundamental long-term importance: The airplane was stretched and its wing lengthened to extend its range and provide more room for sensors. And the aircraft was converted from analog to digital wiring and electronics, which allowed it to carry a wider range of standardized sensors that can simply plug into the airplane’s data bus like computers in a network. The resulting U-2Rs and the TR-1s, both of which had 103-foot wingspans, were 23 feet longer than the U-2 they replaced.
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.