Developing the F-117

In 1977, Lockheed began the top-secret Have Blue project for the Defense Advanced Research Projects Agency (DARPA), the central research and devel­opment organization of the U. S. Depart­ment of Defense. Skunk Works came up with a design that looked like a pyramid with wings and two tails. It was almost invisible to radar when mounted on a pole on the ground, but would it fly? The plane’s unusual shape made it unstable, and it could not have flown successfully without the aid of comput­er technology. Computerized fly-by-wire systems were already in use on planes such as the F-16, constantly adjusting the flight controls to prevent the plane from losing stability and crashing. The secret stealth plane, designated the F-117, was equipped with such a system.

The F-117 was test flown in the Nevada desert in 1981. It was like no other plane. Anything that gave off a radar trace was eliminated from the air­craft, so antennae and sensors were designed to retract into the fuselage. The F-117 had no radar system of its

TECH ‘kTALK

THE F-117

The F-117 Nighthawk is a single-seat airplane powered by two General Electric turbofan engines. It flies at just below the speed of sound (Mach 1). Its principal weapons are two 2,000-pound (907-kilogram) laser-guided bombs, or air-to-surface missiles. The wings and fuselage are aerodynamically blended. They are made of a conventional material, aluminum, but are coated with spe­cial radar-absorbent materials. The Nighthawk weighs about 52,000 pounds (about 23,000 kilograms) when fully loaded.

Подпись: О The Tacit Blue was a research aircraft built to demonstrate that curved surfaces could avoid radar. It flew first in 1982 after several years of development and was retired in 1985.

own to betray its position. The cockpit was coated with a reflective material that radar beams bounced off in all directions. The engine intakes were screened, and exhaust gases were cooled by heat absorbers so that little trace showed on heat sensors.

Initially, the F-117 was not an easy aircraft to fly. Two early prototypes crashed, in 1978 and 1980, but the pro­gram continued with two more test air­craft. The first F-117A was handed over to the U. S. Air Force in 1982 and went operational the following year. It was still top secret, flying only at night. The public became aware of the mystery plane, named the Nighthawk, in 1989, when it took part in operations against Panama. F-117s also flew missions against Iraq during the Gulf War in 1991.