1.  Responsible service

The services are provided in accordance with the provisions contained in the following ICAO Documents:

1. ICAO Annex 2 - Rules of the Air

2. ICAO Annex 11 - Air Traffic Services

3. Doc 4444 - Procedures for Air Navigation Services-Air Traffic Management (PANS/ATM)

4. Doc 8168 - Procedures for Air Navigation Services-Aircraft Operations (PANS/OPS)

5. Doc 7030 - Regional Supplementary Procedures

2.  Area of responsibility

Air traffic services are provided for the entire territory of Mongolia.

3.  Types of services

The following types of services are provided:

1. Area Control Service (ACC) /Radar services are provided in certain sectors and the details are given in subsection ENR 1.6/

2. Approach Control Service (APP)

3. Aerodrome Control Service (TWR)

4. Alerting Service (ALRS)

5. Flight Information Service (FIS)

6. Aerodrome Flight Information Service (AFIS)

4.  Coordination between the operator and ATS

Air traffic services units shall have due regard for the requirements of the operators and if so required by the operator, shall make available to them or their designated representatives such information as may be available to enable them to carry out their responsibilities.

When so requested by an operator, messages (including position reports) received by air traffic services units and relating to the operation of the aircraft for which operational control service is provided by that operator shall, so far as practicable, be made available immediately to the operator or a designated representative in accordance with locally agreed procedures.

5.  Minimum flight altitude

Minimum Sector Altitude (MSA)

Minimum sector altitude shall be established for every instrument flight procedure. The lowest altitude which may be used which will provide a minimum clearance of 300m (1000ft) above all objects located in an area contained within a sector of a circle of 46km (25NM) radius centred on a significant point, the aerodrome reference point (ARP) or the heliport reference point (HRP).

Minimum sector altitude shall be calculated by:

Taking highest obstacle within extended area of 55km (30NM) radius which includes a buffer zone of 9km (5NM).

Adding a clearance of at least 300m (1000ft).

Rounding the resulting value up to the nearest 50m (100ft).

Minimum En-route Altitude (MEA)

The altitude for an en-route segment that provides adequate reception of relevant navigation facilities and ATS communications complies with the airspace structure and provides the required obstacle clearance.

Minimum en-route altitude shall be calculated by:

Taking highest obstacle and terrain in width of that airway.

Adding a clearance of 300m (1000ft) if the terrain and obstacle elevation is not higher than 2000m above mean sea level or adding a clearance of 600m (2000ft) if the terrain and obstacle elevation is higher than 2001m above mean sea level.

Rounding the resulting value up to next 50m (100ft) increment, as appropriate.

Minimum Descent Altitude (MDA) or Minimum Descent Height (MDH)

The Minimum Descent Altitude (MDA) or Minimum Descent Height (MDH) is a specified altitude or height in a Non-Precision (2D) Approach or Circling Approach below which descent must not be made without the required visual reference.

The required visual reference means that section of the visual aids or of the approach area which should have been in view for sufficient time for the pilot to have made assessment of the aircraft position and rate of change of position, in relation to desired flight path. In the case of a circling approach the required visual reference is the runway environment.

Minimum descent altitude (MDA) is referenced to Mean sea level and it is established by rounding up Obstacle clearance altitude (OCA) to the next higher 50m (100ft). In this calculation, aircraft altimeter unit and other required factors are considered. (Doc 8168, VOL II, Figure I-4-5-3 b)

Minimum descent altitude is referenced to the aerodrome elevation or to the threshold elevation if that is more than 2m (7ft) below the aerodrome elevation.

Obstacle Clearance Altitude/Height (OCA/H)

In a non-precision approach procedure, the OCA/H is defined as the lowest altitude or alternatively the lowest height below which the aircraft cannot descent without infringing the appropriate obstacle clearance criteria.

6.  ATS units address list