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The following is an unauthorized version of the Report of the Panel of Experts to the United Nations on Sierra Leone.
This is not the official report. The official report has not yet been released. The report posted here is subject to change by the sanctions committee.
II. AIR TRAFFIC SYSTEMS IN WEST AFRICA
A. Air Traffic Management
278. The Panel was pleased to note that, contrary to the situation elsewhere, FIRs in West Africa do not strictly follow the contours of national boundaries, and that the delimitation of these FIRs is generally in line with operational requirements.
279. The Panel also noted that the present airspace configuration was redefined to take into account the ICAO (International Civil Aviation Organization) recommendation, which requires states to implement area control as soon as possible, with a view to increasing air traffic safety. A lot remains to be done however, especially in Nigeria, Mali, Mauritania, Niger and elsewhere.
280. The layout of the airways, which transit the Region, connects major airports, or the radio navigational aids, which serve these airports. The heaviest traffic flows are the Gulf of Guinea (Abidjan-Accra-Lagos corridor), then the Dakar/Abidjan axis and the North-South traffic flow. The East-West traffic is less dense. The West African airspace is far from being congested.
B. Communications
281. The most frequently used means for Aeronautical Mobile Service (AMS - air/ground and air/air communications) IS the High Frequency (HF), which has an extended range but presents drawbacks on reception, and the Very High Frequency (VHF), whose range is not extended, but which offers greater listening comfort. These technologies operate well on the whole. A study carried out by IATA on this subject in May 2000 shows, on the one hand, that the VHF is increasingly used and has considerably improved, both from the point of view of quality and availability, and that on the other hand, the HF is still the only available mean in several sectors.
282. In several countries in the Sub-region, the Single Sideband (SSB) is used to provide links between the main airport and the domestic airports.
283. The Aeronautical Fixed Service (AFS), which ensures the transmission of flight plans and other aeronautical messages between specific fixed points, operates fairly well, especially at main airports. Performance has been enhanced by the implementation of the SATCOM (Satellite Communications) Project developed by ICAO and financed by the European Development Fund. SATCOM, which uses VSAT (Very Small Aperture Terminal) technology, has facilitated the implementation of several fixed service and speech circuits in the Region. Many VSAT have been installed in the region, and there are other projects under implementation, especially in the vast airspaces managed by ASECNA.
284. The Fixed Service is often backed up, however, or replaced by the SITA (Société internationale de télécommunications aéronautiques) network, a private network generally used by airlines. The 97% availability threshold recommended by ICAO is often never reached.
285. As regards the ATS/DS (direct speech) circuits based on the use of the public telecommunications network, these seem to be operating better in the ASECNA area (Dakar/Bamako, Niamey/Ouaga, etc) because of the similarity of equipment, than they do outside that area (Bobo/Accra, Bamako/Roberts). These ATS/DS circuits enable two controllers working in adjacent centres to exchange traffic data. Usually, when the ATS/DS circuits do not work, controllers use the HF for the coordination. This practice is not recommended. In short, communications remain a weakness.
C. Navigation
286. The main navigational aids in the region operate fairly well. However, many of them have reached their age limit, especially the Instrument Landing Systems.
287. The VORs (VHF Omni-directional Radio Range), coupled or not with DMEs (Distance Measuring Equipment), are implemented in all international aerodromes and are generally operational. The same is true for the NDBs (Non-directional radio beacons), which are used nearly everywhere. All these ground facilities work towards providing safe navigation in the Region.
D. Surveillance
288. The use of radar is very rare in West Africa. The explanation given to the Panel is that ICAO recommends that states should use radar only if the situation really warrants it. If this is taken as a rule, it would apply only to the Gulf of Guinea States (Côte d'Ivoire, Ghana and Nigeria).
289. Thus Ghana has installed radar in Accra to cover the Western sector of its airspace. A project is presently underway which will enable Ghana to cover its entire airspace, including that of Benin and Togo. In Nigeria, the radar is being replaced. That of Abuja operates within a radius of 50 Nautical Miles.
290. A secondary radar system has been undergoing tests in Abidjan for the past few years. Its official commissioning has been delayed because of a problem between the government and ASECNA, the manager of the airspace. It has nonetheless proven very useful. As an example, the Panel was informed that a few hours after a recent takeoff from Accra, an aircraft heading west realized that its navigation instruments were no longer functioning. It therefore decided to land at Accra, its point of departure. Soon after, it was seen on the Abidjan radar screens heading north. The Ivorian controllers were able to guide it safely to its final destination.
291. The Panel was informed that, as part of a surveillance exercise, ASECNA had carried out Automatic Dependent Surveillance (ADS) trials, which had been positive. But for the past two or three years, ASECNA has stopped talking about them.
292. The CNS/ATM (Communication, Navigation, Surveillance/Air Traffic Management) implementation plan (1995-2005) provides for the installation an ADS in Dakar and in Sal Island to monitor the Oceanic FIRs.
293. The absence of radar is strongly felt and all the aeronautical and/or military authorities questioned by the Panel mentioned the problem. Authorities are frequently informed of violations of their airspace by pilots who come across illegal traffic. They are also aware that aircraft operators can operate with impunity in their sphere of sovereignty, without their knowledge. At times, it is local authorities or even local individuals who contact them to inform them of an overflight. The military admit that they do not have the means to intercept such traffic, a common practice elsewhere. Training and refresher course were also mentioned as a major requirement.
294. In spite of the absence of radar, West African air traffic services still provide the classic elements of control, which is to prevent collision between aircraft in the air and on the ground, and to speed up and regulate air traffic generally.