Perhaps sometimes you've wondered, while looking at a ticket, what those 3 letters mean. I think it's obvious that it's the airport code, which indicates where you're departing from and where you're headed. But who determined these letters, and why specifically these letters for this airport? I'll tell you about it now.
IATA 3-Letter Codes of Airports
This is the full name of this code. In Russian, it is the "3-letter IATA airport code." I've previously explained what IATA is; if you missed it, you can read about this organization in this post.
As with the development of the barcode on the boarding pass, the system for encoding airport codes was adopted in Resolution 763 by IATA.
The essence is that each airport or other major transport hub has its own code. Cities can also have a common 3-letter code; for example, St. Petersburg has the same 3-letter code as Pulkovo Airport – LED, and Kaliningrad – KGD.
Where Do the Letters for the Code Come From?
But not just any code. If you look closely at the code and the name of the locality where the airport is located, you'll notice that the code is a kind of abbreviated name of that locality (or airport). For example, I'll take a list of several airports to explain more clearly:
- KALININGRAD = KGD
- KRASNODAR = KRR (why is there a second R here?)
- KRASNOJARSK = KJA
- Moscow, VNUKOVO = VKO
- Moscow, DOMODEDOVO = DME
Code Uniqueness
Okay, it seems clear now. But let's now understand why Krasnodar has a second letter R and why St. Petersburg is represented as LED.
In reality, it's all very, very simple. The code KDR (as one would naturally encode Krasnodar) was already taken by another airport. If you Google "KDR," you'll find that it belongs to an airport in Papua New Guinea, in the city of Kandrian (KANDRIAN = KDR) (a similar set of letters to Krasnodar, isn't it?). Therefore, they simply added an extra letter R.
Now, an important clarification. I think you've already guessed that this is an international encoding system used worldwide, and accordingly, it must be unique. Therefore, airport codes may deviate slightly from the names of cities or airports, but efforts are made to keep them close.
Based on the English alphabet and 3 letters, the maximum number of possible code combinations is 17,576. However, what if we run out of codes? It could happen, but airports aren't built every day; they tend to expand. Moreover, there are many old and inactive airports worldwide, so over time, their codes may be assigned to other airports to avoid using a new possible code.
Why is St. Petersburg, Pulkovo – LED?
Alright, but what about my beloved Pulkovo, St. Petersburg – LED? It doesn't match any of the names in terms of letter combination. Here it's even simpler. There was a time when the city of St. Petersburg was called Leningrad. Therefore, the code received at that time corresponds to LENINGRAD = LED. And no magic!
Back to the USSR!
As much as I may not want to touch on the USSR, I have to. In the USSR, they couldn't go against the world and developed a similar 3-letter coding system, but using the Russian alphabet. Essentially, it was practically an identical analogue of the IATA system, but in Russian.
And Finally, Meet – ICAO
In addition to the International Air Transport Association (IATA), which we discussed above, there is also the International Civil Aviation Organization (ICAO). So, they also developed a coding system, also alphabetical, also in Latin, but this time with 4 letters. But why, if there was already a 3-letter one or not?
In reality, as I write this post, it's a new idea for a new post, and I'll write it later – about the main and fundamental differences between these two international organizations. But the main point here is as follows: airport codes are the only field where the two organizations intersect (for London Heathrow, the IATA code is LHR, and the ICAO equivalent is EGLL). The difference in these codes underscores the differences between the two organizations: IATA airport codes were developed for use by airlines in relation to passengers and clients – they thought about boarding passes and flight reservations. For ICAO, the corresponding list of airport codes is used by pilots and air traffic controllers (or air navigation service providers).
Indeed, I am a witness to that, and in general, I am aware that pilots enter the ICAO airport code, not the IATA code, into their onboard computer – a 4-letter code in Latin.
ICAO Codes
Unlike the IATA code, which was initially developed for simpler understanding (hence the letters from the city/airport name), the ICAO code carries a much deeper meaning and letter combination. The first two letters, according to a special classifier, contain information about the country and region, while the remaining two indicate the order of assignment.
For example, let's take a few airports and look at their ICAO codes:
- St. Petersburg, Pulkovo – ULLI
- Moscow, Domodedovo – UUDD
- Moscow, Vnukovo – UUWW
- Moscow, Sheremetyevo – UUEE
- Kaliningrad – UMKK
- Krasnoyarsk – UNKL
- Novosibirsk – UNNT
- Krasnodar – UKKR
And here's a brief decoding of the first two letters of the code:
- UE – Yakutia
- UH – Far East
- UI – Eastern Siberia and Transbaikalia
- UL – North of the European part
- UN – Central Siberia
- UO – Coast of the Arctic Ocean
- UR – North Caucasus region
- US – Ural region
- UU – Central region
- UW – Volga region
Conclusion
So, today I've introduced you to airport coding. I really hope that now you'll look at those letters differently. As I love civil aviation a lot, I already know many IATA airport codes by heart. Reading the codes of unfamiliar airports, armed with the information provided, I can already guess that, for example, MRV might mean Mineralnye Vody, LAX is Los Angeles Airport, or the most famous airport JFK, named after John F. Kennedy (the IATA code exactly matches his full name – John Fitzgerald Kennedy).
Sometimes, when I want to look up something about a specific airport, I just enter its code in Google. For example, if I enter KJA, the search results immediately show the card for Krasnoyarsk Airport, with the airport's website being the first link. You can use this trick if you need to quickly open the website of a specific airport.
Such is the interesting world of aviation.
Hugs ❤️