The Ethiopian Civil Aviation Authority's Air Navigation Services Directorate has gone through difficult and at times turbulent situations to manage to attain its present status of performance in the communication, Navigation, Surveillance and Air Traffic Management fields.
ICAO Eastern and Southern African Regional office today acknowledges the Air Navigation Services of Ethiopia as one of the best in terms of implementing the Regional Air Navigation Plan and so does the International Air Transport Association,IATA, although there are still some minor shortcomings to deal with.
Presently, more than 97% of the Ethiopian Airspace is covered by means of reliable Extended VHF radio communication system, linked to the Control center (by means of a VSAT satellite network and UHF Link. The Exchange of Data Messages is carried out by means of a fully automated system. Addis Ababa has been one of the ten main Aeronautical Fixed Telecommunication Network (AFTN) stations in the ICAO Africa and Indian Ocean Region and as such fulfilling its international obligations. . Therefore, to improve the service and to catch up with the ICAO plan that is extended to the future the implementation of the Extended ATS Message Handling system has replaced the existed AFTN system recently.
In terms of navigation aids, it deserves mention of the reliable ground based NAV facilities that provide service at the existing International and domestic airports in the country. There are five VOR/DMEs, a DVOR/DME, three Instrument Landing Systems - ILS and a number of NDBs in perfect operational status providing navigation services to the airports and for the en route phases of flights.
The service also has flight inspection and calibration of NAV AIDS and other landing aid system with own specialists and Automatic Flight Inspection system (AFIS).
The department has taken early advantage of GNSS by implementing same for en-route and terminal navigation. Non-precision RNAV instrument approach procedures based on GPS have been designed, validated and put into service since December 2002. No serious issues in terms of track deviation or satellite outage and RAIM warning have been reported to date.
To upgrade the service from procedural control to visual control the surveillance system has been implemented by installing the Primary and Secondary surveillance Radar at Addis Ababa Bole International Airport for terminal (approach) service. In addition, to provide the en route surveillance service covering the entire country air space six Automatic Dependent surveillance Broadcast (ADS-B) systems are installed at the stations where the existing Extended VHF radio communication system are located and interlinked to Control center by VSAT satellite communication link.
To make the service efficient and reliable the Directorate implemented the redundant power supply by installing diesel generators and solar power supplies besides the commercial Hydroelectric power supply which is provided by EEPCO.