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Insertion of new technologies has propelled the capabilities of aircraft
avionics forward. New aircraft are equipped with satellite navigation
capabilities, some with Automatic Dependent Surveillance-Broadcast (ADS-B)
as aids for surveillance. Enhanced processing capabilities in the cockpit
of modern aircraft ensure the aircraft's flight is as efficient as possible.
This new generation of aircraft (and retrofitting the older generation
with enhanced capabilities) presents an opportunity.
With aircraft knowing where they are (with an accuracy better than the
ground knows where they are using radars) and having the ability to broadcast
that information and receive like information, new possibilities arise
for enhanced situation awareness and more collaborative decision making.
Position information can be displayed in the cockpit on a moving map which
could include also terrain information and proximate aircraft. Weather
information from the ground (originating either from the FAA or from the
airline) could be uplinked and displayed, as well. Airport information
(runway in use, visual range, etc.) could be uplinked to the aircraft
and displayed. This integration of information in the cockpit is sure
to enhance pilot situation awareness.
With aircraft equipped with ADS-B, pilots will be able to see the traffic
situation around them. Seeing the traffic situation encourages a more
collaborative partnership between the controller and the pilot. Aircraft
with ADS-B could be assigned to maintain a certain distance behind another
on approach and landing, and the pilot using his ADS-B equipment to aid
in visually acquiring the lead aircraft and in maintaining proper separation.
This collaborative effort has two benefits: effective separation distances
between aircraft on approach could be reduced in some instances, increasing
the capacity at some airports; with the electronic aids, it is possible
that the airport could operate as in visual conditions even when those
conditions would deteriorate, thus maintaining the throughput of the airport
longer.
ADS-B also has the ability to increase safety. With aircraft and ground
vehicles properly equipped, displays in the cockpit would indicate problematic
situations that now lead to runway incursions.
Airborne System Solutions
CAASD is working with the FAA and industry stakeholders in the Safe Flight 21 program. Safe Flight is a  cooperative effort between government and industry, to develop enhanced capabilities for Free Flight based on evolving CNS technologies. There are two major components of the Safe Flight 21 program: the Operational Evaluations in the Ohio Valley, and the Capstone efforts in Alaska.
CAASD is working with the FAA and other partnering organizations to move the research and acceptance of new aircraft capabilities forward. We are working with the Cargo Airline Association and the FAA in the Ohio Valley Operational Evaluations of ADS-B. Using technology developed in CAASD laboratories and transferred to UPS Aviation Technologies for commercialization, equipped aircraft have participated in a number of trials to enhance the state of the art in ADS-B applications. The CAA is particularly interested in the ADS-B applications of flight following. CAA aircraft fly generally at night when visibility is diminished, and the use of ADS-B technology has shown an ability to operate at visual capacities longer. CAASD developed the procedures and the experiment plan, participated in the experiment, and developed the results document.
CAASD is also working in the State of Alaska with the FAA and other participants in the Capstone project. Alaska aviation is challenged. For many in the state, aviation is the only means of getting needed supplies or services since roads are nearly impossible due to extreme cold and rugged terrain. Air taxi services, air ambulance services, air delivery services, etc., are used more in Alaska than in any other part of the U.S.  Much of Alaska is not covered by surveillance radars, so air traffic control is conducted under "non radar rules" which imply pilot position reporting requirements at relatively long time intervals, allowing aircraft to deviate undetected and, so, without warning.
On December 31, 2000, the first ADS-B position report from an aircraft flying in an area not covered by surveillance radars was received at the Anchorage Air Route Traffic Control Center and for the first time, an aircraft symbol was displayed at a controller workstation fully integrated with other traffic. This was revolutionary because radar-like services were, for the first time, being offered in an area without radar coverage. CAASD's research into ADS-B technology and expertise in operational systems and experimental design helped pull it off. The Kushkokwim Delta region of Alaska is a safer place now with this ongoing experiment as plans evolve for an expansion of these new capabilities.
Another aspect of CAASD’s research has produced the cockpit infrastructure necessary for the ADS-B-based radar like services. CAASD produced the Universal Access Transceiver (UAT), a device that can communicate with the ground and with proximate aircraft to exchange position information, and processing capabilities including a moving map where positions of this and proximate aircraft can be displayed. This technology was transferred to UPS Aviation Technologies on the instructions of the FAA for commercial production of those sets to be used in the Capstone exercises.
CAASD has a historic perspective on aircraft systems. Since the early 1970s, MITRE has been producing the logic and prototyping the  equipage of collision avoidance systems, and in the late 1980s, aircraft started to equip with the Traffic Alert and Collision Avoidance System, or TCAS. The TCAS technology was transferred to avionics manufacturers for commercial production.
TCAS is an early implementation of ADS-B-like technology in that aircraft in a given vicinity exchange position and intent information which is then processed aboard the aircraft to determine whether there is a short-term threat to any of the aircraft. In the late 1980s, the Congress of the United States made equipage with TCAS mandatory for all aircraft carrying thirty passengers or more. The TCAS technology is the basis for the standardized collision avoidance system now being advocated by ICAO as the global standard.
Looking at the success of TCAS over the last decade, it is easy to project the anticipated benefits of emerging ADS-B technologies currently slated for the cockpit. The integration of airborne conflict detection via TCAS-like logic with position processing and ADS-B applications presages a revolution in air traffic control. The concepts for such a system are still under investigation at CAASD, Boeing, and other organizations
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