Stealth aircraft

The invention:

The first generation of “radar-invisible” aircraft, stealth planes were designed to elude enemy radar systems.

The people behind the invention: Lockhead Corporation, an American research and development firm Northrop Corporation, an American aerospace firm




Radar

During World War II, two weapons were developed that radically
altered the thinking of the U.S. military-industrial establishment
and the composition of U.S. military forces. These weapons
were the atomic bombs that were dropped on the Japanese cities of
Hiroshima and Nagasaki by U.S. forces and “radio detection and
ranging,” or radar. Radar saved the English during the Battle of Britain,
and it was radar that made it necessary to rethink aircraft design.
With radar, attacking aircraft can be detected hundreds of
miles from their intended targets, which makes it possible for those
aircraft to be intercepted before they can attack. During World
War II, radar, using microwaves, was able to relay the number, distance,
direction, and speed of German aircraft to British fighter interceptors.
This development allowed the fighter pilots of the Royal
Air Force, “the few” who were so highly praised byWinston Churchill,
to shoot down four times as many planes as they lost.
Because of the development of radar, American airplane design
strategy has been to reduce the planes’ cross sections, reduce or
eliminate the use of metal by replacing it with composite materials,
and eliminate the angles that are found on most aircraft control surfaces.
These actions help make aircraft less visible—and in some
cases, almost invisible—to radar. The Lockheed F-117A Nightrider
and the Northrop B-2 Stealth Bomber are the results of these efforts.


 Airborne “Ninjas”

Hidden inside Lockheed Corporation is a research and development
organization that is unique in the corporate world.
This facility has provided the Air Force with the Sidewinder heatseeking
missile; the SR-71, a titanium-skinned aircraft that can fly
at four times the speed of sound; and, most recently, the F-117A
Nightrider. The Nightrider eluded Iraqi radar so effectively during
the 1991 Persian Gulf War that the Iraqis nicknamed it Shaba,
which is an Arabic word that means ghost. In an unusual move
for military projects, the Nightrider was delivered to the Air
Force in 1982, before the plane had been perfected. This was done
so that Air Force pilots could test fly the plane and provide input
that could be used to improve the aircraft before it went into full
production.
The Northrop B-2 Stealth Bomber was the result of a design philosophy
that was completely different from that of the F-117A
Nightrider. The F-117A, for example, has a very angular appearance,
but the angles are all greater than 180 degrees. This configuration
spreads out radar waves rather than allowing them to be concentrated
and sent back to their point of origin. The B-2, however,
stays away from angles entirely, opting for a smooth surface that
also acts to spread out the radar energy. (The B-2 so closely resembles
the YB-49 FlyingWing, which was developed in the late 1940’s,
that it even has the same wingspan.) The surface of the aircraft is
covered with radar-absorbing material and carries its engines and
weapons inside to reduce the radar cross section. There are no vertical
control surfaces, which has the disadvantage of making the aircraft
unstable, so the stabilizing system uses computers to make
small adjustments in the control elements on the trailing edges of
the wings, thus increasing the craft’s stability.
The F-117A Nightrider and the B-2 Stealth Bomber are the “ninjas”
of military aviation. Capable of striking powerfully, rapidly,
and invisibly, these aircraft added a dimension to the U.S. Air Force
that did not exist previously. Before the advent of these aircraft, missions
that required radar-avoidance tactics had to be flown below
the horizon of ground-based radar, which is 30.5 meters above the
ground. Such low-altitude flight is dangerous because of both the
increased difficulty of maneuvering and vulnerability to ground
fire. Additionally, such flying does not conceal the aircraft from the
airborne radar carried by such craft as the American E-3A AWACS
and the former Soviet Mainstay. In a major conflict, the only aircraft
that could effectively penetrate enemy airspace would be the Nightrider
and the B-2.
The purpose of the B-2 was to carry nuclear weapons into hostile
airspace undetected.With the demise of the Soviet Union, mainland
China seemed the only remaining major nuclear threat. For this reason,
many defense experts believed that there was no longer a need
for two radar-invisible planes, and cuts in U.S. military expenditures
threatened the B-2 program during the early 1990’s.

Consequences

The development of the Nightrider and the B-2 meant that the
former Soviet Union would have had to spend at least $60 billion to
upgrade its air defense forces to meet the challenge offered by these
aircraft. This fact, combined with the evolution of the Strategic Defense
Initiative, commonly called “Star Wars,” led to the United
States’ victory in the arms race. Additionally, stealth technology has
found its way onto the conventional battlefield.
As was shown in 1991 during the Desert Storm campaign in Iraq,
targets that have strategic importance are often surrounded by a
network of anti-air missiles and gun emplacements. During the
Desert Storm air war, the F-117A was the only Allied aircraft to be
assigned to targets in Baghdad. Nightriders destroyed more than 47
percent of the strategic areas that were targeted, and every pilot and
plane returned to base unscathed.
Since the world appears to be moving away from superpower
conflicts and toward smaller regional conflicts, stealth aircraft may
come to be used more for surveillance than for air attacks. This is
particularly true because the SR-71, which previously played the
primary role in surveillance, has been retired from service.

See also : Airplane; Cruise missile; Hydrogen bomb; Radar;
Rocket; Stealth aircraft Wikipedia .