without pilots on board will one day navigate safely
in skies filled with all types of aircraft. Sensors
will enable remotely piloted aircraft to be steered
away from other aircraft by operators in control rooms
on the ground.
NASA and several partners in industry have already
test flown an aircraft from a ground station, using
special radar and radios to locate and avoid other
piloted test airplanes that approached the remotely
piloted plane. The most recent flight research took
place in the skies near Mojave, Calif., in April 2003.
A specialized aircraft called Proteus was operated
by a pilot in a control room miles away from where
the airplane was flying on a special test range over
the desert. Other airplanes, including a fast NASA
F/A-18 jet, deliberately made passes toward the Proteus.
Although these approaches had a margin of safety to
ensure they would not actually collide, they were
still close enough to prove that radar in the nose
of Proteus could identify potential collision hazards
with enough clarity, and in time for the ground operator
to change course in a safe direction.
The April flight tests were important because they
showed a remotely piloted aircraft can detect other
airplanes that are not sending out any signals to
show their locations. A year ago, NASA and its research
partners flew tests with Proteus using a radio-based
detection system that identified the presence of other
airplanes that were using transponders to help controllers
locate them. Transponders are used regularly by airliners
and many other aircraft. A transponder sends a radio
signal to enable air traffic controllers to keep track
of aircraft using this device in flight.
Uninhabited aerial vehicles (UAVs) are already expanding
the horizons of flight. They can fly long-endurance
missions that would fatigue an onboard pilot. They
can fly high, where oxygen would be necessary for
human inhabitants. They can fly into dangerous locations
without risking the lives of the operators, who are
safe in a control room far away. Because they do not
need to support the well-being of a pilot onboard,
UAVs can be made smaller, lighter, and with fewer
complex systems than those required of piloted aircraft.
This allows greater performance plus less expensive
aircraft. UAVs already have military reconnaissance
duties, and are being evaluated for a variety of civilian
applications including communications relay and environmental
After the use of remotely-piloted aircraft is made
routine in the airspace system, NASA and its partners
want to automate the
detection devices to enable safe operation of autonomous
aircraft without any human intervention from takeoff
to landing. Safety comes first; if a remotely piloted
or autonomous aircraft loses contact with its ground
operator or experiences other guidance difficulties
in flight, the aircraft has an onboard capability
to fly to a safe place while technicians fix the problem.
This could be as simple as circling in the sky while
other air traffic in the area is advised of the uninhabited
More detect, see and avoid flight tests are planned,
as NASA and its partners look for ways to enable UAVs
to share the skies with all aircraft.
Want to see photos of Proteus and the other aircraft
used in the April detect, see and avoid (DSA) tests?
You can go to: http://www.dfrc.nasa.gov/Gallery/Photo/Proteus/Small/index.html.
Want to learn more about this exciting research? You
can read about DSA on the NASA Dryden Flight Research
Center web site at: http://www.dfrc.nasa.gov/Newsroom/NewsReleases/2003/03-21.html
(also 03-20) in the News Release section.
NASA's Dryden Flight Research Center