Abbreviations and codes
International standard units
Which unit is used for what, grouped by the category it measures.
Longer horizontal distances, such as the length of a route
1 NM = 1 852 m
Horizontal visibility
Used when over 5 000 m
Visibility and RVR under 5 km, runway length
Vertical distances (altitudes)
1 ft = 0.3048 m. FL 100 = 10 000 ft
Also used for vertical distance
Speed of wind and aircraft
1 kt = 1 NM per hour = 1.852 km/h
Usually not used in civil aviation in Europe
Rate of climb or descent
Accurate altitude readings, cabin pressure, altimeter settings
1 hPa ≈ 30 ft
For example the weight of an aircraft
Vital for performance and visibility
Course summary tableThe same categories and units, as a plain list to revise from.
| Category | Unit | Abbr. |
|---|---|---|
| Horizontal distance | Nautical miles, kilometres | NM, km |
| Horizontal distance (visibility, RVR under 5 km) | Metres | m |
| Vertical distance | Feet, metres | ft, m |
| Speeds | Knots, kilometres per hour | kt, km/h |
| Vertical speed | Feet per minute | ft/min |
| Air pressure | Hectopascals | hPa |
| Mass | Kilogram | kg |
| Temperature, dew point | Degrees Celsius | °C |
Time and date
UTC Zulu
Coordinated Universal Time, also called Zulu time. A single standard time for global aviation.
Date time group
Written as year, month, day, then time.
Phonetic alphabet
Used to avoid confusion caused by accents and spelling.
In English, numbers are said as single digits.
The exception
In Danish
ICAO alphabet with pronunciation
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Callsign rules
According to SERA, a callsign must be one of these three types:
No operator, so the registration is the whole callsign.
Last four characters only, so the O drops off. Used by operators who fly by registration rather than by flight number.
Used by most airline flights.
Two forms only, and both shorten the registration and nothing else.
Telephony is the spoken name, not the written code. SAS is written in the flight plan, “Scandinavian” is said on the radio. DTR is written, “Danish” is said. Private aircraft have no telephony at all, so they use the registration marking.
Nationality markers
The start of an aircraft’s registration shows which country it’s registered in.
Green and dashed: not on the course list. Neighbours you will meet around Danish airspace.
Airline designators and callsigns
Three-letter operator designators and the callsign that is said on the radio.
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Not on the course list. Useful to recognise on frequency and in flight plans.
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Ground station callsigns
The abbreviation, and the word that is said.
Location indicators
Four-letter codes. Each letter has a meaning.
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