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Testimony of Chris Pear
Manager of Flight Dispatch Operations
United Airlines

Testimony of Rich Falcone
Manager Technical Operations
American Airlines

before the
National Civil Aviation Review Commission



In this testimony representatives of the joint FAA/industry program known as Collaborative Decision Making (CDM) present the safety benefits of this program to the National Airspace System (NAS). CDM is a philosophy of business, based upon information exchange and collaboration between government and industry, used to create a safer and more efficient (NAS). Through information exchange, all involved parties have a common situational awareness of the NAS and any operational constraints therein. Decisions affecting the safety and efficiency of the NAS can then be made collaboratively to ensure flight safety. Specifically, there are three working groups under CDM which are developing concepts which, when implemented, will directly affect NAS safety. These are: Ground Delay Program Enhancements (GDPE), NAS Status Information, and Collaborative Routing. Each of these groups is made up of representatives from FAA, several airlines, private industry and academia. Their priority is to first determine what policies and procedures need to be changed from the present system and then utilize either existing tools or create new decision support tools to achieve these changes. The CDM representatives recommend that this commission support the continuing work of these groups and embrace the collaborative philosophy of CDM, as these efforts will positively impact the safety of the NAS.




The White House Commission on Aviation Safety and Security has called for "a strong government-industry partnership . . .needed to develop and integrate the research, standards, regulations, procedures and infrastructure needed to support the aviation system of the future." (Final report to President Clinton, February 1997). The CDM program, though not as well known as other aviation incentives, is such a government-industry partnership. Now officially RTCA Special Committee 191 - Collaborative Air Traffic Management (ATM), CDM involves personnel from all aspects of the aviation community: FAA and other government entities, airlines, private industry and academia, who are developing and creating tools to benefit the NAS as a whole. The potential benefits of this type of collaborative effort are significant both economically and functionally. CDM is in the process of examining and implementing near term goals for a future NAS as defined by the Free Flight Action Plan, especially those related to the safety and efficiency of NAS operations. Under RTCA SC 191, the CDM Implementation Group oversees sub-groups to conceptualize and implement specific aspects of CDM. Three of these groups work with elements directly related to aviation safety: Ground Delay Program Enhancements (GDPE), NAS Status Information and Collaborative Routing.

All CDM incentives rely on information exchange and collaboration between government and industry to accomplish their goals. Already, CDM has implemented a tool to enhance the exchange of information among NAS users and operators. The AOCnet, up and running at eight major airlines, is a communications link between Airline Operational Control Centers (AOCs), Air Traffic Control System Command Center (ATCSCC) and Volpe National Transportation Center which allows members two-way data exchange of real time information (i.e. flight schedule information, airport arrival rates, etc.). Funded mostly by the airlines who now use it, this link is an integral part of the information sharing which is key to the CDM program and the implementation of a new NAS. The aforementioned sub-groups are all reliant on the AOCnet to implement their concepts.


This group is the most mature of the CDM Sub-groups. The decision support tools created by GDPE are scheduled to go into prototype operations at San Francisco and Newark airports this winter. The GDPE group has been established to determine what changes are needed in policies and procedures, as well as modifications and enhancements to the actual infrastructure (i.e. FSM, ETMS database, AOCnet). Part of this infrastructure, Flight Schedule Monitor (FSM), enables NAS users to view operational constraints and information from the AOCnet in the same format as ATCSCC. FSM currently allows airlines and ATCSCC to monitor specified airports as well as view specific flight information, airport arrival rates, open arrival slots and other information pertinent to flight operation. FSM gives ATCSCC a complete picture of NAS demand and constraints as well as allowing operators to react quickly to those constraints. Both AOCs and ATCSCC can perform "what if" analyses and view different allocations of resources as well as view the consequences of their actions on the NAS and its users in a matter of seconds.

The safety benefits are still being realized with this tool. Because of its quick processing, FSM allows controllers more time to view varied NAS scenarios and choose the safest method to avoid constraints. Already airlines are using FSM to predict flight fuel needs. When an airport's demand exceeds its capacity, airlines can view the demand and predict delay at that airport. This allows operators to determine the need for extra fuel on flights arriving at that airport which may be delayed in the air, or re-route flights already en-route to the airport which cannot accept delays due to fuel load.


NAS Status Information enhancements of CDM will provide critical safety related information that is currently not available to all users or is currently not disseminated in a timely manner. This group is in the process of prioritizing NAS information which will be made available through the AOCnet and pertains to significant conditions which could affect the safety of flight, such as runway contamination, braking action, turbulence and icing, to name a few. Through the AOCnet, information can be rapidly distributed to all necessary parties, so that ATC and flight operators and crews may make necessary changes to flight operations. NAS information disseminated via the AOCnet would also allow direct communications between individual airlines. This would avoid accidents attributed to delayed information being disseminated by a third party. For example, sudden adverse weather conditions may be known to a pilot of one airline, but unknown to any other party in the NAS. If the pilot reports the conditions to their flight dispatcher, that information can then be immediately made available to any airline accessing the AOCnet. Other airlines can then re-route flights around the weather, thus avoiding hazardous conditions. Currently, it can take anywhere from minutes to hours for pilot information to be distributed outside their own airline. This can cause other aircraft to fly directly into unexpected weather conditions, resulting in passenger or crew member injuries due to turbulence, or even fatal accidents.

NAS Status Information requires the collaboration of government and industry to share information known to them, making public what once may not have been accessible.


The Air Traffic Control (ATC) system has constraints due to volume, weather and other factors that require ATC to alter the filed routes of flights to meet the needs of the NAS. Currently, FAA flow managers and system users must rely on verbal communications (i.e. conference calling) to decide on a course of action to avoid disruptions to the orderly flow of traffic. The RTCA report on Free Flight recommends that the FAA explore alternative technologies and techniques which will allow FAA flow managers and aircraft operators to engage in a more effective collaborative decision making process. The goal of CDM's Collaborative Routing Sub-group is two-part: (1) create a system allowing ATC and the users to negotiate routes which avoid congestion and delays in the NAS and (2) allow users and ATC to negotiate routes that avoid adverse weather while minimizing negative impacts on the NAS. Collaborative Routing seeks to create policies, procedures and technology that will allow the users to view ATC constraints and which allow the user to plan their flights within these constraints. The current lack of common situational awareness may lead to route selection that is not in the best interest of individual carriers or that may compromise the safety of the flight.

Information pertinent to the safety of flights would be made available through collaborative routing efforts. Through collaborative routing efforts between ATC and the users, flights will be able to better avoid adverse weather conditions and routings which could endanger the flight. Airline dispatchers choose flight routes for several reasons: time and fuel considerations, en-route contingencies and weather conditions. Many times, a flight can only accept limited changes, if any, in the route that has been filed for it. ATC changes to a flight route can lead to changes in meteorological, topograghical and geographic characteristics of the flight path which eliminate the possibility of using contingency plans previously agreed upon by the captain and dispatcher. These unexpected route changes can drastically affect the safety of the flight itself. However, if the users have access to the constraints which ATC is working under, they would have the ability to route flights accordingly, in a manner which will allow both the flight and ATC to meet operational and safety needs.

The Collaborative Routing Sub-group is in the process of developing concepts to achieve these goals. Collaborative Routing has divided itself into two groups: (1) an Operational group with personnel from both the FAA and airlines who will develop scenarios and the necessary procedures to achieve the goals of the group and (2) a Technical group with personnel from academic institutions, industry and airlines who will implement the technology recommended by the Operational Sub-group by either using existing tools or developing new ones. The Collaborative Routing Group will also utilize the AOCnet to send NAS constraint information to all users. April 1998 has been set as a target date to implement an operational model using existing technology as a starting point for collaborative routing efforts. At the same time, both the operational and technical members of the Collaborative Routing Sub-group will continue to develop a long-term solution.


The CDM concepts are destined to become the first initiatives of the Free Flight Action Plan to come to fruition and they establish a new philosophy in air traffic management through a cooperative decision making approach. Never before have such positive and mutually beneficial accomplishments been witnessed than what has occurred because of the collaboration between FAA and airlines in recent years.

The key elements to success are industry cooperation and the rapid exchange of information. GDPE has already validated the benefit of cooperative decision making as prototype operations are soon to begin. Information exchange is made possible through the AOCnet, which is already established and provides the conduit for expeditious dissemination and acquisition of operational and safety-related information.

Not only will the CDM efforts improve efficiency in the NAS, promoting better allocation of resources and improved passenger service, but most important are the potential enhancements to aviation safety, which is and will remain the first precept in airline operations.