The U-Deuce- page 3 | How Things Work | Air & Space Magazine
Current Issue
October 2014 magazine cover
Subscribe

Save 47% off the cover price!

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.

Air & Space Magazine | Subscribe

(Continued from page 2)

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.

Comment on this Story

comments powered by Disqus