International Civil Aviation Organization

World-wide CNS/ATM Systems

Implementation Conference

Rio de Janeiro, 11 – 15 May 1998

WW/IMP–WP/52

19/3/1998

Item 3

Agenda Item 3:	Financial matters

THE CNS/ATM SYSTEMS AND THEIR BENEFITS TO THE AFI REGION

(Presented by 53 African Contracting States1)

Action Paper

SUMMARY

This paper is an overview of the elements of the CNS/ATM Systems and underscores the benefits that the AFI Region could derive from the implementation of such a concept and the planning process undertaken by the APIRG Group for that purpose.

1.	The CNS/ATM System

1.1	The new CNS/ATM Systems stemming from the research conducted by the FANS Committee created by the ICAO Council in 1983 in order to assess the effectiveness of new technologies intended to remedy the shortcomings of the existing systems, marks the introduction of space technology and computerization in air traffic control and the navigation system.

1.2	In the field of communications, the Aeronautical Mobile Services (AMS) is at the present time reliant on HF links for en-route communications and VHF links in terminal areas. Such types of links have got insuperable limitations such as atmospheric interferences for the former and the optical range for the latter. The use of satellite links for en-route communications enables to overcome such a handicap and secure control over the oceans and deserts. This is considered to be a significant benefit for the AFI Region known for its deserts and large oceanic areas. The introduction of satellite links in the AMS will make possible not only the establishment of reliable pilot - controller speech links, but also the opening of data links between airborne systems and those in the control centers on ground. The VHF data link which has been maintained in terminal areas will offer the same benefits. The secondary surveillance radar (Mode S) will also take advantage of data links with flying aircraft. The introduction of the data link between the aircraft and control centres on ground should stir up air traffic management by establishing a real dialogue between airborne computers and computers operated from control centers on ground.

1.3	In the field of navigation, at the present time, flying aircraft are reliant on radio aids on the ground which, unfortunately, cannot be installed either over the oceans or in desert areas. In the new CNS/ATM systems, the Global Navigation Satellite System (GNSS) which, gradually, will replace ground aids, should enable the aircraft to determine its position, direction and speed in any part of the world for any en-route, approach and landing phases. This is a significant advantage/benefit for the AFI Region which has got many shortcomings in the field of radio aids.

1.4	At the present time, the surveillance of the airspace is possible only in terminal areas or continental areas equipped with radars. For the en-route traffic over oceans and uninhabited areas, air traffic controllers are unable to detect any fortuitous departure from the flight plan and convey to pilots on time the remedial action to be taken due to the poor quality of links by decametric waves. To determine the space occupation status, controllers have been resorting to position reports supplied by pilots by giving them a free hand to resolve situations of possible conflicts.

1.5	In the new CNS/ATM environment, the aircraft will take advantage of the Automatic Dependent Surveillance (ADS) by transmitting via satellite through data link its position (in three dimensions) and other useful data provided by flight management computers. Such data transmitted automatically would be displayed to the controller on a screen similar to a radar screen that will enable him/her to follow the flight evolution while detecting possible conflicts. Thus, ADS makes possible the resolution of surveillance problems in an efficient and cost- effective manner as compared with the radar facility.

2.	Benefits to Africa

2.1	The introduction of satellite links and computerization in airspace management will enable Africa to remedy most of the deficiencies due to the shortcomings of the existing systems.

2.2	The Global Navigation Satellite System (GNSS) will relieve the AFI Region from the limitations of navaids and will offer a homogeneous airspace to air traffic control.

2.3	The Automatic Dependent Surveillance (ADS) will also make possible a better control of the en-
route traffic in remote airspace with a scattered but ever increasing traffic.

2.4	The AFI Region can only derive benefits from the new CNS/ATM systems that should enable it to overcome its shortcomings at a less cost.

2.5	The implementation of CNS/ATM will result in the improvement of flight safety and air transport economy.

3.	CNS/ATM Implementation Plan in the AFI Region

3.1	Realizing these benefits, the AFI Planning and Implementation Group (APIRG) commenced planning of the implementation of the system early in the AFI Region and developed the AFI CNS/ATM Implementation Plan which was adopted at its tenth meeting held in Dakar from 3 to 7 June 1996.

3.2	The above Plan was endorsed by the ICAO AFI 7th Regional Air Navigation meeting (AFI/7 RAN) held in Abuja, Nigeria in May 1997 and adopted by the ICAO Council.

3.3	This Plan spells out the systems to be implemented both by States and users. The AFI Region has been divided into 10 areas of routing (A/R) in accordance with the traffic flows and appropriate equipment specified to each of these areas.

3.4	For each AR, ATM objectives were set the attainment of which is dependent upon the implementation of the CNS means. Also for each AR, it has been planned to set up a Co-ordination Group (ICG) for the implementation of such means.

3.5	With respect to communications of the Mobile Service, these means range from data links VHF/Satellite up to the extension of full coverage in VHF.

3.6	As regards the Fixed Service, these means range from the upgrading of AFTN, the AFTN/SITA interface up to the gradual introduction of procedures based on bits compatible with the ATN.

3.7	With regard to navigation, APIRG has established a Task Force on the introduction of the GNSS in the Region. The actual purpose is to study the various augmentation systems available and propose to APIRG the most suitable for the AFI Region.

3.8	As for Surveillance in remote areas, ADS implementation shall be made possible through GNSS introduction.

3.9	In terminal areas with high traffic density, VHF coverage should be extended to 150 NM at least while the VHF data link will be introduced in a gradual manner.

3.10	For navigation in terminal areas, GNSS may initially be used as a supplemental to traditional means during the first phase of the Plan. GNSS will be used as supplemental enroute navigation means and as primary enroute means in designated airspace.

3.11	With respect to surveillance, position reporting shall remain the main procedure along with the secondary surveillance radar, possibly Mode S.

3.12	Trials in ADS are currently in progress in the Region by ASECNA. ADS and CPDLC trials are also in progress in Johannesburg Oceanic FIR, Johannesburg FIR and Canaries FIR. Results are encouraging.

4.	Implementation of the Plan

4.1	The implementation exercise should be coordinated at regional and inter-regional levels.

4.2	At the regional level, meetings of Implementation Co-ordination Groups (ICGs) should be convened given that these groups are responsible for defining the equipment and setting implementation time frames.

4.3	The implementation of the CNS/ATM Plan will require:

a)	Immediate installation of VHF extended range stations for communications, VOR/DME for enroute navigation at a number of sites and implementation of AFS (AFTN/ATS DS) links between FICs/ACCs.

b)	The installation of ground and airborne equipment for digital links between aircraft and control centres.

c)	Putting airborne equipment on board aircraft for the purpose of satellite navigation

d)	For ADS operation, control centres to have the required data links and aircraft be suitably equipped.

e)	The installation of appropriate GNSS augmentation systems where required.

f)	For control in busy terminal areas, the provision of secondary surveillance radar, and in selected busy TMAs Mode S data link.

g)	Training of personnel and the design of operational procedures.

5.	Recommendations

5.1	It is recommended that the Conference:

a)	take note of the progress made in Africa in the planning and implementation of CNS/ATM systems as part of the global CNS/ATM Plan;

b)	note the requirements specified in para 4.3 necessary for the successful implementation of CNS/ATM in the region; and

c)	urge financial institutions to favorably consider financing the timely implementation of CNS/ATM in order to meet the identified requirements.

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