Communication Navigation Surveillance / Air Traffic Management (Cns / Atm) Beyond 2012
5.3 Air Traffic Service (ATS):
The implementation of CNS elements improves ATS services, incorporating advanced technology into existing or basic function instead of merely replacing them. Consideration should be given to using the operational functions and new elements of the system in parallel with the existing ones for a limited period of time, in order to evaluate their operational application and familiarize pilots and controllers with the new procedures. Automated aids will be introduced, such as a conflict prediction and resolution advisory capability. Standards, and recommended practices (SARPs) and procedures to be introduced should facilitate the operation of aircraft with different equipment in the same ATS environment.
5.4 Free Flight/Autonomous Flight:
The concept of free flight/ autonomous flight developed in the United States and originally conceived to give aircraft more maneuvering capacity, with the support of available new technologies. It also emphasizes the need for users to decide of their own upon their schedules, routes, and altitudes, thus reducing delays and costs. The most important thing is the principle of maintaining a safe separation between aircraft. This principle is based upon two strips of airspace, known as protection strips and the alert strips, whose dimensions are determined by the aircraft speed, performance, and CNS equipment. The protected zone of the one closet to the aircraft can never overlap with the protected zone of another aircraft. The alert zone extends beyond the protected zone and the aircraft can maneuver freely until its alert zone touched by another aircraft. If this happens, the controller can give one or both pilots heading vectoring or other restrictions in order to ensure the separation. Eventually, most of the orders will be sent by data link, which will be integrated into an air-ground communication network. Furthermore, airborne computers and GPS satellite will enable pilots, assisted by controllers, to use cockpit displays of traffic (CDTI) to select the best separation options.
6.0 Conclusions:
The benefits of the communication system are the links between ground and airborne automated systems will be more direct and effective. Improved data processing and transfer between operators, aircraft and ATS providers will alleviate the congestion of voice channel, reduce the possibility of making mistakes and allow for a more efficient link between ground and airborne systems.
The benefits of the new navigation system is the availability of an improved guidance and position capability in any part of the world will enhance operation efficiency, reducing flight time and the fuel required through navigation. The availability of the NPA for runways lacking ground navigation aids or that are served by unreliable navigation aids: will reduce delays, alternates, over flights and cancellations due to bad weather. The availability of a GNSS-supported PA through GBAS or SBAS coupled with airborne ones will also offer advantages over exiting equipment. The capability of providing approach guidance for more airports could attract from those where delays due to congestion are common. By reducing such delays, operators will save flight time and fuel. Eventually use of the GNSS for all phases will result saving for operator due to the reduction of airborne equipment types. It will also reduce maintenance and capital costs. Advance integration techniques with inertial reference systems (IRS) will make possible to operator with more precise approach i.e. CAT-II & III. The availability of satellite navigation will enable the gradual deactivation and phasing out of conventional ground aids which will provide significant saving to the service provider.
The benefits of the new surveillance system are with use of ADS. ADS applied in airspace without radar coverage will evolve to a point where services will be furnished that are very similar to those provided by radar control, including aircraft position display on a ground screen. ADS use leads to a reduction of separation minima used in non-radar airspaces. The exiting regulatory separation over oceanic airspace may be reduces by one-half, thus doubling the capacity of the oceanic routes. ADS uses also adds operational flexibility to ATC for controllers are able to respond better to user flight preferences.
The benefits of the free flight option is improved safety through advanced conflict detection and resolution technique, More flexibility for managing flight operations and better prediction of airspace conditions and their effects on such operation, better tools for decision making by pilots, air traffic controller, and flight dispatchers, saving from reduced fuel consumption and lower aircraft operating costs, reduced use of flow control, environmental improvements due to reduction in exhaust emissions in en-route flights, approaches at airports, more precise position and time and possibility of sharing information between pilots and controllers.
References:
- International Civil Aviation Organization, Global Air Navigation Plan for CNS/ATM systems (Doc9750)
- International Civil Aviation Organization, Fifth meeting of the Aeronautical Mobile Communications Panel (AMCP), working paper No.-6 “ Report on Assessment of CNS Digital Link”.
- International Civil Aviation Organization, Manual on testing of Radio Navigation aids (Doc 8071).
- International Civil Aviation Organization, Guidelines for the introduction and operational use of Global Navigation Satellite System (Circular 267)
- International Civil Aviation Organization, Eleventh Air Conference (September/ October 2003) working paper no.188, draft report of committee B on Agenda Item 6.
- International Civil Aviation Organization, ADS and ATS Data link Applications (Circular256)
- International Civil Aviation Organization, Draft Airborne Separation Assistance system circular.
- Seamless Sky by H.V Sudarsan Published by “Ashgate Publishing limited, England”.