The U-Deuce | How Things Work | Air & Space Magazine
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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“THE AIRPLANE IS NOTHING LIKE WHAT POWERS FLEW,” says Bryan Swords, currently the chief engineer for the U-2S at Lockheed Martin Aeronautics Company’s Palmdale, California office. Swords is referring, of course, to Francis Gary Powers, who, four years after overflights began over the U.S.S.R., Poland, and East Germany, had the unfortunate distinction of being shot down in a U-2 near Sverdlovsk in the Soviet Union on May 1, 1960. “It’s 40 percent larger, it’s been re-engined, it’s got a new cockpit, and it’s been rewired to support extremely modern, stronger sensors,” says Swords.

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The U-2’s adaptability has kept it in service since the mid-1950s and should keep it off the endangered species list for another half-century. The airplane originated as a response to a desperate need for reconnaissance over the Soviet Union and Eastern Europe. Bell, Fairchild, and Martin were among the firms invited to submit proposals. But when he heard about the competition, Clarence L. “Kelly” Johnson of Lockheed submitted a design as well. Johnson was the chief engineer at Lockheed’s Skunk Works in Burbank, California, and his entry was basically a powered glider based on a modified F-104 Starfighter fuselage mated to very long wings and a centerline landing gear. The CL-282, as it was called, was a simple and adaptable reconnaissance platform. The Air Force promptly rejected it, but the CIA grabbed it up and code-named it Aquatone. It first flew in 1955.

Today, the aircraft has a new name: Senior Year, and many of its systems have the prefix Senior, as in Senior Ruby and Senior Glass. Less officially, the large, black, sinister-looking spycraft is known as the Dragon Lady.

Even from the start, the U-2’s evolution has been driven by its sensors. “The Air Force comes to us with a capability requirement,” says Mark A. Mitchell, Lockheed Martin U-2 program office manager. “There’s a new sensor out there, a new operational concept, and they want the airplane to be able to support it.” Mitchell’s job is to respond to the Air Force’s wants in a rapidly changing world. During World War II, he says, a large military target or a city would be photographed by speedy, high-flying reconnaissance airplanes and then hit by hundreds of heavy bombers. That mode of operation continued into the cold war, though with one change in plan: If there were a U.S.-Soviet exchange, just a few bombers would be deployed, with nuclear bombs.

But the link between reconnoitering a target and attacking it is undergoing a revolutionary change. The new way of doing things is called network-centric, or net-centric, warfare. The military is turning reconnaissance systems into an information network like the Internet, in which all the image and signals collectors are connected to one another, as well as to the combatants in the air and on the ground. Soldiers searching for Al Qaeda forces in Afghanistan, for example, can now send a request to task a nearby reconnaissance satellite to scour the area, and can download the images it captures to their laptops and see them in seconds. If it’s urgent, a U-2 in the vicinity could be directed to fly in for a closer look. And if the U-2’s sensors confirm what the satellite saw, the troops know it almost instantly. The Department of Defense calls this arrangement the Global Information Grid, and it is in continuous operation around the world.

A ground operations center on the other side of the world can also direct the intelligence collectors to get specific data, provide aircraft navigation instructions, operate the sensors, communicate with the aircraft, with satellites, and with other collectors, and then direct the collectors to communicate with one another to share information and to deliver the intelligence to soldiers, sailors, or marines. The military calls this “fused” intelligence, and well over $1 billion is being spent to fully integrate the Dragon Lady into the system.

To take sensor management as an example, technicians at control panels thousands of miles away can direct the sensors while its pilot looks on (his main job is to fly his aircraft). Using a satellite to relay the data, a U-2 looking and listening deep inside North Korea sends its take back to the United States. And it gets its instructions from controllers at home the same way.

What has changed dramatically, Mitchell adds, is that a single U-2 can train an array of sensors, including imaging systems, antennas, and receivers that intercept radio signals, on a target. Then that information can be sent directly and immediately to a single F-16 pilot, who can obliterate the target with a single precision-guided bunker-busting bomb. Twelve O’Clock High and its armadas of heavies is gone forever.

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.

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.

And soon there will be more eyes: Hughes is developing a compact, lightweight, electro-optical infrared sensor called the DB-110 that will collect high-resolution imagery in two bands for any or all of three image types: continuous ground coverage, spot coverage, and stereo 3-D, all three modes distributed via data link.

If one system can be said to represent the future U-2, it is the SPIRITT—the Spectral Infrared Remote Imaging Transition Test—which is being developed by the Air Force Research Laboratory at Wright-Patterson Air Force Base outside Dayton, Ohio. The idea is to create a day-night, high-altitude, super-sensitive sensor test bed that will combine optical images and radar to get an almost instant, high-quality picture of the target. The system will be so sensitive it can spot even obscured targets, like tanks hiding in thick forests. The foliage-penetrating program even has its own name: TUT, for Targets Under Trees. It will use data from very-high-frequency synthetic aperture radar and other sensors. And the whole integrated package is being designed to fit into the Dragon Lady’s Q-bay and into its unmanned counterpart, the Global Hawk. Pat Fillingim, a spokesperson for the Air Force Research Laboratory’s Sensors Directorate, which is developing SPIRITT, describes it as potentially “a new sensor suite for an old lady.”

At one point, someone also had the idea of using the high flier to photograph satellites. The plan was to extend the nose four feet and put in a camera like those in reconnaissance satellites, using a standard mirror set at a 45-degree angle. The passing satellite’s image would reflect off the mirror and into the same kind of long-focal-length parabolic mirror that was used in the KH-9 Hexagon reconnaissance satellite. But it was decided that the elaborate system would cost more than it was worth, so it was killed.

Distant Whispers
Other collectors carried by the U-2S listen. One suite receives both communication traffic and other kinds of electronic emanations, such as radar signals. These signals can be relayed directly to deployable ground stations—DGSs—in the field, or, via satellite relay, anywhere on the globe. No one at Lockheed Martin will say that the relay spacecraft are Defense Satellite Communications System IIIs, several of which are in geostationary orbit 22,300 miles above the equator. In time of war, voice and coded communication can be pulled in by the U-2S and relayed directly to friendly forces.

The signals intelligence systems include Senior Ruby, which monitors radar emissions; Senior Spear, which eavesdrops on communication traffic; and Senior Glass, which gathers signals intelligence and the capabilities of which are still classified. They are carried in the two super pods.

The U-2S also has what Mitchell calls a “superlative” new defensive system. It is the AN/ALQ-221, which listens for threats, displays them, and then automatically employs the appropriate countermeasures, including transmissions that confuse the attacker. All the pilot has to do is turn it on.

The U-2S is equipped to know when it is being tracked on radar and infrared sensors on hostile aircraft or, more likely, surface-to-air missiles. Radar relies on accurate timing, and most countermeasures work to corrupt that timing dependence. The aircraft also have the capability to reduce their heat signatures, as well as systems to defend against an infrared-seeking missile. And the Air Force is experimenting with a communication intercept system that would not only pick up attacking pilots talking to one another but would almost immediately transmit messages to confuse the pilots—in their own voices. It will almost certainly go in the U-2S.

The sensors are interconnected and redundant—they back one another up. For example, the radar and the infrared optics can produce a single image, and instead of all the airplane’s avionic systems and sensors running on separate cables and connectors, a data bus similar to the network cable connection for a group of personal computers routes signals to the appropriate sensors. And it can even send them to a backup if the primary one is inoperative.

Background Noise
The close integration of all the electronics makes the U-2S an unprecedented intelligence collector, but so many sensitive electronics can also bite one another in new ways.

Discussion of the U-2S’s signals intelligence capabilities—what and how sensitive they are—is carefully guarded by the military. The radio monitoring system has high-frequency, very-high-frequency, and ultra-high-frequency bands that pick up transmissions with an antenna farm that sprouts from the belly of the aircraft. Their sensitivity can be inferred by the fact that as new systems are added the existing ones can interfere with them, and even the wiring that moves data around the aircraft can reduce the quality of what they collect.

“What will a new sensor do to the other systems?” Jim Kaplan, Lockheed’s mission systems senior manager, wonders aloud. The wiring that carries electrical power creates enough electromagnetic noise to degrade the intelligence. Some of the systems can interfere with their own mission, but the U-2S is supposed to pick up signals, not listen to its own wheezing.

So with Block 10, the Power/Electro-Magnetic Interference Program, every aircraft is completely rewired with shielded, grounded, low-emission copper, fiber optic, and other cables. And the word “power” means providing enough electrical generators to carry out current missions while having enough in reserve for the future without having to rewire yet again.

The update called Block 20 is the most radical and important. It is formally known as the Reconnaissance Avionics Maintainability Program—RAMP. Less formally, it is called the glass cockpit, and it converts the U-2S cockpit to a current digital standard.

That New-Airplane Smell
Comparing the old instrument panel and the new one shows the difference between the two aircraft vividly. The analog panel was crowded with the two dozen or so little gauges and dials that showed heading, airspeed, altitude, engine performance, turn-and-bank angle, and the rest. There was even a telescope that showed the pilot the ground below. Many of the instruments had to be scanned regularly, with the pilot interpreting their readings and performing a lot of mental gyrations to maintain a picture of the airplane’s position and attitude in three-dimensional space.

The glass cockpit is dominated by three six- by eight-inch multi-function displays—small TV screens arranged in a compact triangle. These take the same information and combine it into single interactive displays. All three are completely interchangeable. Each can display the route the aircraft is on, its location on that route, and significant geographic features, such as towns and lakes. And they do it in color: Land is tan and water is light blue. Or they can provide a closeup of the terrain below without forcing the pilot to peer through a telescope.

People in the program say that the point is better maintainability, not just improved performance. They also emphasize that common parts are used whenever possible. When it was decided to replace the old optical telescope used to scan the ground below with an electronic eye that would display a similar picture on one of the multi-function displays, a standard commercial Sony camera was modified to withstand the minus-76-degree Fahrenheit temperature at altitude. Use of available equipment is called COTS, for commercial off the shelf.

Other improvements involve the life support systems (see “Life Support: Flying in Rarefied Air,” p. 24), which have always been plagued with problems in flights at ultra-high altitudes and lasting hours.

Unmanned aerial vehicles, or UAVs, don’t have those problems. UAVs are also the U-2S’s implacable rivals. The Global Hawk, one of the newest and largest UAVs, is manufactured by Northrop Grumman’s Ryan Aeronautical Center in San Diego (see “Send in the Global Hawk,” Dec. 2004/Jan. 2005). Its promoters note that it can fly its long-duration mission without risking a life. Its detractors in the U-2S fraternity note that it cannot think.

It is Lockheed Martin policy not to get into mud-slinging with its rivals and instead to take the safe there’s-plenty-of-work-for-everybody stance—what is officially called a “balance” between manned and unmanned systems. But some individuals can’t resist discreetly straying across the company line. They quietly explain that the human in the cockpit can override the flight program to take advantage of new target opportunities, evade a sudden, unexpected threat, or cope with an unpredictable flying environment. The point is made by color pictures hanging around the office that show a helmeted head with the caption “The Ultimate Computer.”


 

Sidebar: Life Support: Flying in Rarefied Air

Like the U-2s themselves, pressure suits have steadily evolved. Francis Gary Powers’ suit was primitive compared to Rob “Skid” Rowe’s custom-fitted, $250,000, 1034-type suit. Rowe is the Skunk Works chief U-2 pilot, and he likes to say that he wears his cockpit, which is a self-contained environment that weighs 35 pounds. In the event of rapid decompression at high altitude, the suit would instantly fill with air to keep the nitrogen in his blood from forming bubbles and bringing on the painful bends. The suit is made of Nomex, a DuPont-developed fabric that is both tough and flame retardant. And whereas Powers’ suit was olive green to help him evade the enemy if he bailed out, the 1034 and others like it are yellow or orange for the opposite reason: to enhance a pilot’s visibility to rescue crews. There are 249 model 1034 pressure suits in the world, Rowe says, and they are used by about 90 pilots. The suits are so carefully integrated with the airplane that the switches on the instrument panel are sized for the suit’s thickly-gloved fingers.

The helmet, which locks into the suit’s round collar, has the standard two visors, one clear and one dark, found on all military helmets. But it also has a quarter-inch hole in it through which the pilot on a long flight can dine by uncapping a toothpaste-size tube of food, screwing it into a five-inch-long plastic cylinder, sticking the cylinder through the hole and into the mouth, and squeezing. The pilot can choose from a wide variety of fruits, vegetables, and meat dishes such as beef stew. Every tube has a light blue sticker that lists its contents, such as "FOOD VARIETY: Peaches." All of them are similar to baby food, which figures, since they are made by Gerber. Unlike the jars at the grocer’s though, the tubes cost $3. Orders are taken during suit up, and the food is put in the cockpit by technicians, who yell the menu to the pilot just before the canopy comes down and seals.

At the other extreme, there is the waste disposal system, which varies according to the gender of the pilot. Women wear a diaper like those used on the space shuttle. (The first female Air Force pilot flew a U-2S in the mid-1990s, and there are now three mission-qualified female pilots in the Ninth Reconnaissance Wing at Beale Air Force Base in California, which operates the aircraft and deploys it around the world. The fifth woman to fly it is waiting to begin training.) Men use a urine collection device, a molded latex tube that is fitted to the pilot and has a clip to close it off at the end. The long tube hangs from an opening in the white cotton underwear that is worn under the pressure suit. “Occasionally,” says Mark Mitchell, “various people on tours would like to see a pilot suit up. It was always interesting to walk out of the locker room in your underwear with a long tube hanging out of your crotch.”

The pressure suit has a valve on its left leg. The UCD is connected to the valve during suit up, and while the pilot is strapping into the cockpit, a technician takes a clear plastic tube that comes out of the other side of the valve and jams it into a receptacle on the control column that sends the urine into a container under the floor in front of the seat. But the setup doesn’t always work, Mitchell says. “There are more than a few pilots who finished the mission with a very wet foot.” Before missions, pilots eat high-protein, low-residue meals, such as steak and eggs.

 

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