Mobile phones may foil stealth bombers

Mobile phones may foil stealth bombers

Radar evading stealth aircraft are overrated. They are only hidden from radar to the front of aircraft. Airborne radar "looking down" or to their side can detect them. Very high altitude drones could carry directional AESA radar to look down over an area and locate "stealth" aircraft from above. In addition, slow B-2s and F-117 bombers can attack only at night since they are easy to see in daylight. Even at night, fighters can use infrared sensors and even a spotlight to find them. Recall that Yugoslav air defenses somehow tracked and shot down an F-117 at night in 1999, probably using older long-wave radar. As a result, American stealth aircraft are escorted by non-stealthy EA-18F jamming aircraft and fighters.

The new "stealthy" F-22 and F-35 is difficult to track on radar as it is inbound, but newer infrared sensors can pick up the heat signature of its body glowing from air friction, especially if it flies supersonic. Newer Russian MIG-29s have infrared search and track systems that can find aircraft out to 100 miles, and MIG-29s in Serbia are equipped with spotlights, an idea used by World War II night fighters. In addition, LIDAR (laser-radar) can be employed to find aircraft by measuring the laser reflection of objects found while scanning the skies. The Europeans have adapted simple stealth features to the Eurofighter, but rejected the total stealth idea. Other ways of tracking stealth aircraft have appeared as this article reveals.

Mobile phones may foil stealth bombers

By Robert Uhlig in London

America's multi-billion-dollar stealth bombers could be rendered obsolete by a British invention that uses existing mobile telephone masts to detect and track aircraft that were previously invisible to radar. US stealth fighters and bombers such as the F117, B1 and B2 played key roles in the Gulf and Kosovan wars as they are almost impossible to detect using conventional radar. However, the ease with which the mobile telephone mast system - developed at a laboratory in Hampshire - can be used to detect the aircraft has greatly concerned the military.

Mr. Peter Lloyd, the head of projects at Roke Manor Research, said: "I cannot comment in detail because it is a classified matter, but let's say the US military is very interested." Stealth aircraft, each of which costs at least $A3.6 billion, are shaped to confuse radar. A special paint absorbs radio waves, reducing the radar signature to the equivalent of a gull in flight. The Roke Manor scientists discovered that telephone calls sent between mobile phone masts detected the precise position of stealth aircraft with ease. "We use just the normal phone calls that are flying about in the ether," Mr. Lloyd said. "The front of the stealth plane cannot be detected by conventional radar, but its bottom surface reflects very well."

Mobile telephone calls bouncing between base stations produce a screen of radiation. When the aircraft fly through this screen they disrupt the phase pattern of the signals. The Roke Manor system uses receivers, shaped like television aerials, to detect distortions in the signals. A network of aerials large enough to cover a battlefield can be packed in a Land Rover. Using a laptop connected to the receiver network, soldiers on the ground can calculate the position of stealth aircraft with an accuracy of 10 meters with the aid of the GPS satellite navigation system.

"It's remarkable that a stealth system that cost £60 billion [$158 billion] to develop is beaten by £100,000 mobile phone technology," Mr. Lloyd said. "It's almost impossible to disable a mobile phone network without bombing an entire country, whereas radar installations are often knocked out of action with a single bomb or missile."

The Telegraph, London