GEN 2 Tables and Codes

GEN 2.1 MEASURING SYSTEM, AIRCRAFT MARKINGS, HOLIDAYS

1 Units of measurement

The table of units of measurement shown below will be used by aeronautical stations within Doha TMA and for air and ground operations.

For measurement ofUnits used
Distance used in navigation, position reporting, etc. — generally in excess of 2 nautical milesNautical Miles (NM) and tenths
Relatively short distances such as those relating to aerodromes (e.g. runway lengths)Metres (m)
Altitudes, elevations and heightsFeet (ft) or Metres (m)
Horizontal speed including wind speedKnots (kt)
Vertical speedFeet per minute (ft/min)
Wind direction for landing and taking offDegrees Magnetic (°M)
Wind direction except for landing and taking offDegrees True (°T)
Visibility including runway visual rangeKilometres (km) or metres (m)
Altimeter settingHectopascal (hPa)
TemperatureDegrees Celsius (°C)
WeightMetric tonnes (t) or Kilogrammes (kg)
TimeHours and minutes (hhmm), beginning at midnight UTC

2 Temporal reference system

2.1 General
2.1.1 Co-ordinated Universal Time (UTC) and the Gregorian calendar are used by air navigation services and in publications issued by the Aeronautical Information Service. Reporting of time is expressed to the nearest minute, e.g. 12:40:35 is reported as 1241.
2.1.2 Local time is 3 hours ahead of UTC.

3 Horizontal reference system

3.1 Name/designation of system
3.1.1 The geographical co-ordinates indicating Latitude and Longitude are expressed in terms of the World Geodetic System–1984 (WGS-84) geodetic reference datum.
3.2 Identification and parameters of the projection
3.2.1 Projection is expressed in terms of Qatar National Datum-1995 (QND-95).
3.3 Ellipsoid
3.3.1 Ellipsoid is expressed in terms of World Geodetic System–1984 (WGS-84) ellipsoid.
3.4 Datum
3.4.1 The World Geodetic System–1984 (WGS-84) is used.
3.5 Area of application
3.5.1 The area of application for the published geographical coordinates coincides with the area of responsibility of the Aeronautical Information Service of the State of Qatar. This includes the entire territory and airspace over the high seas encompassed by Doha Terminal Control Area (TMA).
3.6 Use of an asterisk to identify published geographical coordinates
3.6.1 An asterisk (*) will be used to identify those published geographical coordinates which have been transformed into WGS-84 coordinates but whose accuracy of original field work does not meet the requirements in ICAO Annex 11, Chapter 2 and ICAO Annex 14, Volume I, Chapter 2.

4 Vertical reference system

4.1 Name/designation of system
4.1.1 The vertical reference system corresponds to Mean Sea Level (MSL).
4.2 Geoid model
4.2.1 The geoid model used is the Earth Gravitational Model–1996 (EGM-96).

5 Aircraft nationality and registration marks

5.1 The nationality mark for aircraft registered in the State of Qatar is the Letter A, followed by the figure 7, i.e. A7. The nationality mark is followed by registration mark consisting of a three letter group. e.g. A7BCB

6 Public holidays

NameDateDuration of holiday in number of days
Note:
  1. An asterisk (*) against a date in the table indicates that it may vary by approximately Plus (+) or Minus (-) one day.
  2. A double asterisk (**) against the 'number of days' indicates that it may be Minus (-) one day depending on the number of days in the month of Ramadan (29 or 30 days).
  3. For holidays of more than one day, the date given is the first day.
Qatar National Day18 December1
National Sports Day11 February1
EID AL FITR28 July*7**
EID AL ADHA04 October*5