by John
DeGaspari,
Associate Editor |
In a test that took place several
years ago, a small, pilotless biplane took off from Cook Field in Dayton,
Ohio. A team led by the inventor Charles Kettering had developed the airborne
contraption, conceived as a top-secret weapon to
deliver explosives against enemy troops.
That was 1918, toward the end of World War I. The craft was the first
practical unmanned airplane.
Its descendants today seem like wonders from the cutting edge of technology.
And, in many ways, they are. Their promise for military and peaceful uses
seems only to grow. But the Predator and other drones, which have become
an integral weapon of air supremacy over Iraq and Afghanistan, have their
roots in the very earliest days of conflict in the air.
The first unmanned aerial vehicle took the name of its chief engineer.
The Kettering Bug measured just 6 feet across and 5 feet long, was powered
by a small two-stroke engine built by the Ford Motor Co., and had enough
lift to carry a 250-pound warhead. It was, according to Dik Daso, curator
for modern military aircraft at the National Air and Space Museum in Washington,
D.C., the first practical example of an unmanned aerial vehicle in the
form of an airplane.
 |
| The Bug took off from a track. At a predetermined
time, the wings released, causing the plane to plunge to the earth,
where it detonated. Photos
courtesy of the U.S. Air Force Museum |
The plan was to launch the Bug from a track, from which it would fly
along a straight path toward enemy lines. A counter would keep track of
the number of revolutions made by the propeller, and at the desired time,
fuel would be cut off from the engine and the Bug would plunge to earth
and explode. The Bug had no direct control. An altitude sensor and pneumatic
controls based on bellows from a player piano controlled its climb.
The airplane had a tendency to circle in the sky, Daso said. In early
tests, the Bug orbited the fields, buzzed the brass in observation stands,
and crashed. Eventually, a gyroscope was used to get it to fly fairly
straight.
The Army pushed ahead, and later built about 50 of the planes. Toward
the end of 1918, aviator Henry "Hap" Arnold, who would later
command the U.S. Army Air Forces in World War II, was dispatched to Europe
to convince General Pershing to use the Bug against Germany. The two never
got to speak and, in any case, the war ended before the Bug could be deployed
in combat.
 |
| Unmanned aerial vehicles such
as this circa 1946 target drone were built by the Radioplane Co. to
train antiaircraft gunners during World War II. |
Yet the Kettering Bug got people thinking, and interest in using unmanned
aerial vehicles in combat continued throughout the 20th century. One idea,
under the Aphrodite Project during World War II, was to enlist torn-up
B-17 and B-24 bombers that were no longer suitable for combat missions.
A two-man crew took up the "weary" bomber, packed with explosives,
and armed it in the air. The crew then bailed out over British territory
and the bomber, equipped with radio control technology developed in the
1920s and 1930s, was steered from another plane that followed, to maneuver
it over enemy lines.
The Allies launched 11 of these bombers during the war, but none was very
successful, and they were easy to shoot down, Daso said. The project was
scrapped when Joseph Kennedy, the older brother of future President John
F. Kennedy, and his fellow crewman were killed when the weary bomber they
were flying blew up over England. Proponents such as Arnold viewed unmanned
aerial vehicles as a way of avoiding the losses sustained by crewed aircraft
flying over heavily defended targets, Daso said.
Part of the lineage of unmanned aerial vehicles is their use as targets.
Starting in 1939, a company called Radioplane manufactured its first unmanned
aircraft that would be used by the U.S. Army Air Corps to train gunners.
"They would fly these big model airplanesat the time, very
high-tech controlled modelsand shoot them down," said Doug
Fronius, the target programs director for Northrop Grumman Corp. in San
Diego. Northrop Grumman acquired Radioplane in 1962, giving it entrée
to the unmanned aircraft business.
TARGET PRACTICE
In 1999, Northrop Grumman boosted its presence in target aircraft further
by acquiring Ryan Aeronautical, the company that built the Spirit of St.
Louis for Charles Lindbergh in 1927. In 1948, Ryan was one of 14 companies
to respond to a U.S. Air Force proposal for a jet-powered target aircraft.
Ryan won the award and produced the first jet-powered target, the Q2C,
which made its first flight in 1952. The Q2C evolved into the BQM34 Firebee,
which is in service today.
The real value of air power in World War I was its role in observation
and artillery spotting, according to Daso. Unmanned aerial vehicles were
ideally suited for this purpose: Cameras were light, and would get lighter.
 |
| Weary bombers, such as the radio-controlled
B-17G Flying Fortress, were used with small success as flying bombs
during the World War II. |
In October of 1962, the downing of a U2 spy plane prompted a project
to put a camera on the Firebee, Fronius said. The program was scrapped
when the Cuban Missile Crisis ended shortly thereafter, but the seed was
planted to use unmanned aerial vehicles for reconnaissance.
When the United States became involved in the conflict in Southeast Asia,
unmanned aerial vehicles were outfitted with film cameras, and also flew
electronic warfare missions and electronic surveillance, Fronius said.
Real-time delivery of information was not common at the time. Although
transmitting capabilities existed, more often cameras were retrieved and
the film developed later on.
 |
| World War II era target drones
preceded unmanned aerial vehicles for surveillance in the coming decades. |
Fronius said the era saw the development of specially designed unmanned
aerial vehicles, not merely converted target craft. Some were quite sophisticated,
capable of flying at high altitudes and for long periods of time. He added
that the industry still did not implement computational power, digital
payload development that allowed the use of stealth cameras, or the Global
Positioning System. Those developments were key to distinguishing later
unmanned aerial vehicles from earlier versions.
During the 1980s, the desire to keep pilots out of harm's way and
advances in technology came together to focus new attention on unmanned
aircraft, Fronius said. In late 2002, the U.S. Department of Defense issued
a "roadmap" for the development of unmanned aerial vehicles
over the next 25 years and outlined plans to develop unmanned aerial vehicles
by every branch of the service.
Overall, the DOD invested about $3 million in unmanned vehicle development
in the 1990s, and another billion dollars since 2000. It plans to invest
another $10 billion over the next decade. Today, the number of unmanned
aerial vehicles in the field stands at 90; that number could quadruple
by 2012. U.S. aerospace companies have unmanned aerial vehicles under
development to handle a wide range of missions, those commonly characterized
as "the dull, the dirty, and the dangerous"that
is, long-duration flights, sampling of hazardous materials, and exposure
to hostile action.
CIVILIAN FLIGHT
Unmanned aerial vehicles may also serve civilian uses. NASA recently concluded
a program known as Environmental Research Aircraft and Sensor Technology.
The goal of the program, which was started in 1994, was to develop unmanned
aerial vehicles and instruments that could be used in science missions
too risky for NASA's current science research aircraft.
One of the final steps of the program was to run "detect, see,
and avoid" demonstrations to test the feasibility of flying unmanned
aerial vehicles in the proximity of other aircraft, with and without transponders.
 |
| On Feb. 23, 2003, the Northrop
Grumman futuristic unmanned Pegasus X-47A completed a 12-minute test
flight at China Lake, Calif. |
A follow-up program, called Access Five, will lay the regulatory groundwork
that would allow a business case to be made for bringing unmanned aerial
vehicles into the commercial market. Besides NASA, the program will also
include the Department of Defense, Federal Aviation Administration, and
six airframe manufacturers. It will also address technical issues, such
as the ability to sense and avoid other aircraft, and secure command and
control links, according to Jeffrey Bauer, who will be heading up the
program.
Any decision to integrate unmanned aerial vehicles into national airspace
will lie with the FAA.
Bauer sees the civilian applications of unmanned aerial vehicles as compelling.
One obvious application for unmanned aircraft is in homeland defense,
and he said there have been discussions with the U.S. Coast Guard along
those lines.
He said that other government agencies, involved with forestry, land resources,
and disaster management, have expressed interest in unmanned aerial vehicles.
While it is too early to predict exactly where these initial efforts will
lead, the groundwork is being laid to take unmanned aerial vehicles to
the next level.
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