Airport codes

[Covenant]

Please excuse this dumb question from a non-industry ignoramus.

Why are there two airport code schemes in existence? The ones that I know best are the 3-letter ones like LGW, LHR, etc. But I've also noticed that pilots often use the 4-letter ones like EGKK and EGLL.

I'm guessing that EG is for English airports, and so this system must also be an international one (presumably other countries use other two-letter prefixes).

So, why are there two schemes? In what different circumstances are the two schemes used? Is one just for us plebs and the other for pilots? Is it to do with map symbology?

Enquiring mind wants to know :)

[G-NADS]

The EGxx codes, i.e. EGLL, EGKK and EGSS are what is known as ICAO (International Civil Aviation Organisation) codes. These exist to identify all airports covered by the ICAO.
These are used by pilots, ATCOs etc.

The LHR and LGW codes are normally used by the airlines, ticketing agencies and passengers to help identify them.

[Covenant]

Thanks G-NADS!

[rolling circle]

ICAO location codes are used mainly on the Aeronautical Fixed Telecommunications Network (AFTN) and are assigned to geographical locations where there is a station forming part of the Aeronautical Fixed Service (AFS), this may not be an airport. For instance, the locator EESA is allocated to the European Space Operations Centre in Darmstadt, Germany.

The first letter of the ICAO code identifies the AFS routing area (E = Northern Europe, C = Canada, K = USA, etc). Where there is more than one country within a routing area, the second letter identifies the country (EG = Great Britain, ES = Sweden, EF = Finland, etc)

In these cases the third and fourth letters identify the geographical location, sometimes obvious and sometimes not (EGST = ElmSetT but EGKC = Bognor Regis ??).

In the UK, stations with a common third letter may be grouped into one identifiable geographical area (TF = Fairoaks, TI = Leavesden, TK = Oxford, TN = Reading). Stations with the third letter D, O, Q, U, V, W, X and Y are military (EGDL = RAF Lyneham, EGDY = RNAS Yeovilton, EGUH = Strike Command HQ, High Wycombe).


IATA codes on the other hand, are designed for the airlines and are more intuitive than ICAO codes. For example, you would not easily connect the ICAO code LFPG with Paris/Charles de Gaulle unless you used it reasonably frequently, the IATA code (CDG) is, however, a little more obvious.

The situation in the USA is a little difference, there being a direct connection between the IATA and ICAO codes. Here, for example, the IATA code for Dallas, Forth Worth is DFW and the ICAO code is KDFW. This is a fine system until you run out of letters - who would guess that the IATA code X14 referred to the airport at La Belle, Fl - ICAO code KX14. Mind you, who would care?

There are a number of websites that will give you a decode of ICAO locators, I'm not sure about IATA codes - anyone?

[Blue Boy]

This link should allow you to get IATA & ICAO airport codes. Works even if you only have the City name:

http://www.ar-group.com/icaoiata.htm

BB

[Chilli Source]

IATA 3-Letter codes may be found on: www.flyaow.com/citycodea.htm (http://www.flyaow.com/citycodea.htm)

[Covenant]

Wow.. thanks rolling circle - a very thorough answer. I do have one more question though: if the "E" in first letter of the ICAO code represents the Northern Europe AFS routing area, then why do French stations start with "LF"? Is there more than one letter designated to Northern Europe, or is France just a special case (as usual)? :)

[Flap 5]

Each country has it's own first two letters. The UK is EG, Spain LE, Italy LI, France LF, etc..

[rolling circle]

Northern Europe means 'really' Northern Europe. The boundary between AFS routing areas E and L runs along the southern borders of Belgium (EB), Germany (ED/ET) and Poland (EP) and the northern borders of France (LF), Switzerland (LS), Austria (LO) and the Czech Republic/Slovakia (LK).

Flap 5 - not quite correct, the first letter, as I described in my first post, is the AFS routing area, the second is the country. Hence UK, Ireland, Belgium, Netherlands, Luxembourg, Germany, Poland, Denmark, Norway, Sweden and Finland, which are all in routing area E, share the same first letter (E).

[expedite_climb]

I shall soon have a program available which decodes airfield identifiers, and provides other info, such as rwy, atis, 24 hr etc. Mail me if you want the web site