Free flight (air traffic control)
Encyclopedia
Free flight is a developing air traffic control
method that uses no centralized control (e.g. air traffic controllers). Instead, parts of airspace are reserved dynamically and automatically in a distributed way using computer communication to ensure the required separation between aircraft. This new system may be implemented into the U.S. air traffic control system in the next decade. Its potential impact on the operations of the national airspace system
is disputed, however.
. True free flight eliminates the need for Air Traffic Control (ATC) operators by giving the responsibility to the pilot in command
. This gives the pilot the ability to change trajectory
in mid-flight. With the aid of computer systems and/or ATC, pilots will be able to make more flight path decisions independently. As in most complex systems, distributed yet cooperative decision making is believed to be more efficient than the centralized control characterized by the current mode of air traffic management.
s, they increased the need for air traffic management (ATM). ATM created Instrument Flight Rules
(commonly known as "IFR") to manage the growing numbers of aircraft. This helped control air traffic, but required a significant amount of time, effort, and resources to maintain IFR flight.
In 1968
, the Federal Aviation Administration
issued the High Density Airport Rule to reduce the amount of aircraft in a given airport. Twenty years earlier Crocker Snow used television cameras to locate his position when flying an aircraft. He sent up signals to the aircraft so they could get a third person perspective of the aircraft’s surrounding. This idea worked but was too costly and was impractical. In the 1960s transponders removed the need to use television cameras.
Other problems that occurred in the air traffic industry were the OPEC fuel crises
and the Professional Air Traffic Controllers Organization (PATCO) strike of 1982 resulting the firing of thousands of controllers by President Ronald Reagan. This showed how vulnerable air transportation was to economic forces.
The key components of free flight were identified in 1971 by United Airlines systems manager William Cotton, although the technology to implement it was not available for another two decades.
In the 1970
's the GPS satellite navigation system was deployed by the US Department of Defense and the aviation industry saw the opportunity to use GPS for potentially more efficient air traffic management capabilities through an increased use of this capability coupled with automation enabled by it.
In 1991
the International Civil Aviation Organization
created the Future Air Navigation System Panel. The Panel produced descriptions of satellite-based technology applications and their use in air traffic management. A larger role emerged for "user define trajectory" that became known as "free flight" by the mid-1990s.
The first hearings on implementing free flight were held in August 1994 by Representative Collin Peterson (D-Minnesota), chair of the House subcommittee with investigative jurisdiction over the FAA.
In 1995 David Hinson
, the FAA administrator, organized a task force to draw up detailed plans to implement free flight. The report, issued in October that year called for three phases; phase I ended at the end of 2002, the others have not been started. Free flight was patented by the FAA in 2001.
As of yet, true free flight applications exist only on a small scale in selected airspace operations where only the most well equipped aircraft operate such as at high altitude by commercial airliners. There are many versions of free flight being conceived for the Next Generation Air Transportation System
(NGATS). The Free Flight vision is expected to slowly emerge over the next 20–30 years as NGATS emerges from billions of dollars of development, testing, careful transition planning, training, and deployment of ground-based and airborne systems by all types of aircraft. Key elements of NGATS include the Automatic Dependent Surveillance-Broadcast
(ADS-B) to be fully deployed by 2013 and what can be expected to be an ever-evolving, net-centric information application called the System Wide Information Management
System or "SWIM".
Unrestricted - In the unrestricted region there will be very little guidance from ATC since aircraft density will be low. Pilots will have a great deal of flexibility to exercise free flight in this area. However, it may become complicated when bad weather is calculated into the equation. Pilots may have to adjust their course to avoid inclement weather. In doing so other pilots attempting to avoid the conditions may cross path with each other. ATC will have to assist the pilots and guide them through this issue.
Transition – Slightly restricted however pilots retain some flexibility to exercise free flight.
Restricted - The freedom of the pilot has been restricted significantly.
Problems with this method include complete surveillance information assurance, communication with different equipment, smaller aircraft incapable of carrying the equipment, and the possibility of a system malfunctioning. It is extremely difficult to have total assurance of all air traffic. If two aircraft flying with different equipment encounter each other, the equipment’s data will have to be sent to the receiving equipment as well as the normal information such as speed. Larger planes will have no problems with the equipment but smaller aircraft will have problems communicating to each other if it lacks an essential component. Surely if this was a one on one scenario it would be easy to solve but if multiple aircraft were involved the difficulty of finding a solution compounds. Lastly, if a system fails or the software has a programming error the aircraft and other aircraft will be flying blind.
In this approach the aircrew will not have the full situational awareness experience in the airborne approach. Aircrew will not be able to handle uncertainties or help out with the uncertainties in this approach. If one aircraft does not follow the directive ATC issues the directive will have to be reissued and in turn increase the workload of ATM operators.
Air traffic control
Air traffic control is a service provided by ground-based controllers who direct aircraft on the ground and in the air. The primary purpose of ATC systems worldwide is to separate aircraft to prevent collisions, to organize and expedite the flow of traffic, and to provide information and other...
method that uses no centralized control (e.g. air traffic controllers). Instead, parts of airspace are reserved dynamically and automatically in a distributed way using computer communication to ensure the required separation between aircraft. This new system may be implemented into the U.S. air traffic control system in the next decade. Its potential impact on the operations of the national airspace system
Airspace class (United States)
The United States airspace system's classification scheme is to provide maximum pilot flexibility with acceptable levels of risk appropriate to the type of operation and traffic density within that class of airspace - in particular to provide separation and active control in areas of dense or...
is disputed, however.
What is Free Flight?
Free flight is a new concept being developed to take the place of the current air traffic management methods through the use of technologyTechnology
Technology is the making, usage, and knowledge of tools, machines, techniques, crafts, systems or methods of organization in order to solve a problem or perform a specific function. It can also refer to the collection of such tools, machinery, and procedures. The word technology comes ;...
. True free flight eliminates the need for Air Traffic Control (ATC) operators by giving the responsibility to the pilot in command
Pilot in command
The pilot in command of an aircraft is the person aboard the aircraft who is ultimately responsible for its operation and safety during flight. This would be the "captain" in a typical two- or three-pilot flight crew, or "pilot" if there is only one certified and qualified pilot at the controls of...
. This gives the pilot the ability to change trajectory
Trajectory
A trajectory is the path that a moving object follows through space as a function of time. The object might be a projectile or a satellite, for example. It thus includes the meaning of orbit—the path of a planet, an asteroid or a comet as it travels around a central mass...
in mid-flight. With the aid of computer systems and/or ATC, pilots will be able to make more flight path decisions independently. As in most complex systems, distributed yet cooperative decision making is believed to be more efficient than the centralized control characterized by the current mode of air traffic management.
History
Free flight began as an effort to become less dependent on the human factor and more dependent on the growing technology of its day. As airlines expanded their fleets in the 19601960 in aviation
This is a list of aviation-related events from 1960:-January:* January 1 – Fiji Airways is reconstituted, becoming equally owned by BOAC, Qantas, and Tasman Empire Airways....
s, they increased the need for air traffic management (ATM). ATM created Instrument Flight Rules
Instrument flight rules
Instrument flight rules are one of two sets of regulations governing all aspects of civil aviation aircraft operations; the other are visual flight rules ....
(commonly known as "IFR") to manage the growing numbers of aircraft. This helped control air traffic, but required a significant amount of time, effort, and resources to maintain IFR flight.
In 1968
1968 in aviation
This is a list of aviation-related events from 1968:- Events :* In the 1968 White Paper on Defence, the British Labour government announces that the Royal Navys aircraft carrier force will be phased out as soon as the United Kingdom has completed its withdrawal from Malaysia, Singapore, and the...
, the Federal Aviation Administration
Federal Aviation Administration
The Federal Aviation Administration is the national aviation authority of the United States. An agency of the United States Department of Transportation, it has authority to regulate and oversee all aspects of civil aviation in the U.S...
issued the High Density Airport Rule to reduce the amount of aircraft in a given airport. Twenty years earlier Crocker Snow used television cameras to locate his position when flying an aircraft. He sent up signals to the aircraft so they could get a third person perspective of the aircraft’s surrounding. This idea worked but was too costly and was impractical. In the 1960s transponders removed the need to use television cameras.
Other problems that occurred in the air traffic industry were the OPEC fuel crises
1973 oil crisis
The 1973 oil crisis started in October 1973, when the members of Organization of Arab Petroleum Exporting Countries or the OAPEC proclaimed an oil embargo. This was "in response to the U.S. decision to re-supply the Israeli military" during the Yom Kippur war. It lasted until March 1974. With the...
and the Professional Air Traffic Controllers Organization (PATCO) strike of 1982 resulting the firing of thousands of controllers by President Ronald Reagan. This showed how vulnerable air transportation was to economic forces.
The key components of free flight were identified in 1971 by United Airlines systems manager William Cotton, although the technology to implement it was not available for another two decades.
In the 1970
1970 in aviation
This is a list of aviation-related events from 1970:-January:* January 1 – Nord-Aviation, Sud-Aviation, and SEREB merge to form SNIAS .* January 31 – Mikhail Mil dies, aged 61-February:...
's the GPS satellite navigation system was deployed by the US Department of Defense and the aviation industry saw the opportunity to use GPS for potentially more efficient air traffic management capabilities through an increased use of this capability coupled with automation enabled by it.
In 1991
1991 in aviation
This is a list of aviation-related events from 1991:-January:*January 16 – Eastern Air Lines is dissolved after 64 years of operation. Many of its remaining assets are parceled out to American and Continental Airlines....
the International Civil Aviation Organization
International Civil Aviation Organization
The International Civil Aviation Organization , pronounced , , is a specialized agency of the United Nations. It codifies the principles and techniques of international air navigation and fosters the planning and development of international air transport to ensure safe and orderly growth...
created the Future Air Navigation System Panel. The Panel produced descriptions of satellite-based technology applications and their use in air traffic management. A larger role emerged for "user define trajectory" that became known as "free flight" by the mid-1990s.
The first hearings on implementing free flight were held in August 1994 by Representative Collin Peterson (D-Minnesota), chair of the House subcommittee with investigative jurisdiction over the FAA.
In 1995 David Hinson
David R. Hinson
David Russell Hinson is an American aircraft pilot and former head of Midway Airlines .David R. Hinson is best known for the three years, 1993 to 1996, during which he served as Administrator of the Federal Aviation Administration as an appointee of President Bill Clinton.Hinson oversaw the...
, the FAA administrator, organized a task force to draw up detailed plans to implement free flight. The report, issued in October that year called for three phases; phase I ended at the end of 2002, the others have not been started. Free flight was patented by the FAA in 2001.
As of yet, true free flight applications exist only on a small scale in selected airspace operations where only the most well equipped aircraft operate such as at high altitude by commercial airliners. There are many versions of free flight being conceived for the Next Generation Air Transportation System
Next Generation Air Transportation System
The Next Generation Air Transportation System is the name given to a new National Airspace System due for implementation across the United States in stages between 2012 and 2025. The...
(NGATS). The Free Flight vision is expected to slowly emerge over the next 20–30 years as NGATS emerges from billions of dollars of development, testing, careful transition planning, training, and deployment of ground-based and airborne systems by all types of aircraft. Key elements of NGATS include the Automatic Dependent Surveillance-Broadcast
Automatic dependent surveillance-broadcast
Automatic Dependent Surveillance-Broadcast is a surveillance technology for tracking aircraft as part of the Next Generation Air Transportation System ...
(ADS-B) to be fully deployed by 2013 and what can be expected to be an ever-evolving, net-centric information application called the System Wide Information Management
System Wide Information Management
System Wide Information Management is a Federal Aviation Administration advanced technology program designed to facilitate greater sharing of Air Traffic Management system information, such as airport operational status, weather information, flight data, status of special use airspace, and...
System or "SWIM".
Regions
The regions are broken up into unrestricted, transition, and restricted.Unrestricted - In the unrestricted region there will be very little guidance from ATC since aircraft density will be low. Pilots will have a great deal of flexibility to exercise free flight in this area. However, it may become complicated when bad weather is calculated into the equation. Pilots may have to adjust their course to avoid inclement weather. In doing so other pilots attempting to avoid the conditions may cross path with each other. ATC will have to assist the pilots and guide them through this issue.
Transition – Slightly restricted however pilots retain some flexibility to exercise free flight.
Restricted - The freedom of the pilot has been restricted significantly.
Airborne
In the airborne approach, the separation responsibility is entirely with the pilots, operating under self separation conditions. In its truest form this is the fundamental nature free flight. The pilot is responsible for detecting and resolving problems while in flight. Computers will help aid the aircrew in this matter. Information, such as weather reports or other aircraft position, is forwarded from ATC to the aircraft so the pilots can decide the best course of action to take. The surveillance system can either be on the ground or on-board the aircraft.Problems with this method include complete surveillance information assurance, communication with different equipment, smaller aircraft incapable of carrying the equipment, and the possibility of a system malfunctioning. It is extremely difficult to have total assurance of all air traffic. If two aircraft flying with different equipment encounter each other, the equipment’s data will have to be sent to the receiving equipment as well as the normal information such as speed. Larger planes will have no problems with the equipment but smaller aircraft will have problems communicating to each other if it lacks an essential component. Surely if this was a one on one scenario it would be easy to solve but if multiple aircraft were involved the difficulty of finding a solution compounds. Lastly, if a system fails or the software has a programming error the aircraft and other aircraft will be flying blind.
Ground
All of the data is sent to ATC and pilots requests a particular flight path. Communication will be from aircraft to ATC instead of aircraft to aircraft.In this approach the aircrew will not have the full situational awareness experience in the airborne approach. Aircrew will not be able to handle uncertainties or help out with the uncertainties in this approach. If one aircraft does not follow the directive ATC issues the directive will have to be reissued and in turn increase the workload of ATM operators.
Mixed Focus
Mixed focus approach which is a combination of both the airborne and ground approach. AOC initially sends route to aircraft and ATM. If the aircrew does not like the route it sends the route changes to ATM and AOC.Separation
Aircraft separation is divided up into the Protected Zone and the Alert Zone. In the larger zone, called the "alert zone", the system informs the aircraft through one of the three approaches that an aircraft is in the vicinity. It acts as a flag and merely alerts the aircrew. In the protected zone, the area must remain sterile of all foreign objects. It is the minimum distance anything can approach. The system should alert the aircrew before anything comes close to it but if it manages to enter the protected zone aircrew will take evasive maneuver to avoid a collision.Conflict and detection method using Center-TRACON Automation System
Center-TRACON Automation System (CTAS) receives data from aircraft trajectory, atmospheric model, aircraft performance, and other contributing factors. Based on the information it receives it will calculate the best trajectory though equations and logic. CTAS is currently being used on a small scale.See also
- Next Generation Air Transportation SystemNext Generation Air Transportation SystemThe Next Generation Air Transportation System is the name given to a new National Airspace System due for implementation across the United States in stages between 2012 and 2025. The...
- ADS-B
- TCAS
- GPS
- System Wide Information ManagementSystem Wide Information ManagementSystem Wide Information Management is a Federal Aviation Administration advanced technology program designed to facilitate greater sharing of Air Traffic Management system information, such as airport operational status, weather information, flight data, status of special use airspace, and...
- Self Separation (aircraft)
External links
- NGATS
- Free Flight Phase 1
- Wired: "Free Flight"
- Small Aircraft Transportation Systems (SATS) project at NASANASAThe National Aeronautics and Space Administration is the agency of the United States government that is responsible for the nation's civilian space program and for aeronautics and aerospace research...
- CBSNews:"Flying Cars Ready To Take Off"