Everything Everywhere Daily: History, Science, Geography & More - Airport Codes

Episode Date: May 18, 2021

If you’ve done your share of flying, you are probably familiar with the three-letter airport codes which identify every commercial airport in the world. Airports like DFW, LGA, and HOU are easy to figure out. However, why is there an X in LAX? How did Washington Dulles wind up with IAD? And what is the deal with almost every airport code in Canada? Learn more about airport codes and the weird logic behind them on this episode of Everything Everywhere Daily. Learn more about your ad choices. Visit megaphone.fm/adchoices

If you've done your share of flying, then you're probably familiar with the three-letter airport codes which identify every commercial airport in the world. Airports like DFW, LGA, and HOU are pretty easy to figure out. However, why is there an X in LAX? And how did Washington Dulles wind up with IAD? And what's the deal with almost every airport code in Canada? Learn more about airport codes and the weird logic behind them on this episode of Everything Everywhere Daily. What if your perceptions about the past were wrong? ThruLine is a podcast that takes you back in time to uncover the parts of the story that may have gone unnoticed.

It effectively turned day into night. And how it shaped the world now. Time travel with us every week on the ThruLine podcast from NPR. This episode is sponsored by audible.com. My audiobook recommendation today is Sky Gods. The Fall of Pan Am by Robert Gant. Sky Gods is the saga of America's most glamorous airline, from its meteoric ascent to its plunge into extinction.

Pan Am blazed the way across the world's oceans with its magnificent clipper ships, launched the first international jet service, was the first to fly the behemoth 747, was the lead customer for America's SST and the Concord, and was even taking reservations for the first commercial flights to the moon. You can get a free one-month trial to Audible, and two free audiobooks by going to Audibletrial.com slash

everything everywhere, or by clicking on the link in the show notes. The history of airport codes dates back to before airplanes were even invented. The United States National Weather Service was created after the Civil War. They would take weather observations at military bases around the country and would

transmit the weather reports via telegraph to other bases. To facilitate sending the reports over telegraph, codes were developed for American cities. These two-letter codes, were shorthand for telegraph operators. When commercial aviation developed in the United States in the 1930s, pilots began to use the National Weather Service codes to identify the cities they flew to.

However, there were two big problems. First, not all U.S. cities had a weather service code. And second, there weren't enough two-letter combinations to cover all the cities, especially if the system were to be used outside of the United States. There are only 676 possible two-letter combinations. To solve these limitations, a three-letter system was developed. Assuming that every combination of letters was used, there are 17,576 possible three-letter combinations. This three-letter system was eventually codified by the International Air Transport Association, or the IATA.

Today, they are in charge of assigning the three-letter codes to airports and municipalities around the world. The IATA codes are only given out to airports with regular commercial flights. If you were to include every minor landing strip and airport in the world, including those which have already been closed, then there would be 46,465 in the world. There is another set of codes that are also used for airports that have four letters. These four letter codes are assigned by the International Civil Aviation Organization, or ICAO. The ICAO is a UN-based intergovernmental organization, whereas the IATA is a trade group. The four-letter ICAO airport codes are used for official purposes, and most airline passengers have no clue what the codes are. For the purposes of the rest of this episode, I'll be focusing on the IATA codes, which are the ones we all use when booking flights, and are predominantly displayed on our luggage tags.

So, why are the airport codes the way they are? They fall into several rough categories. The first category are the codes that make perfect sense. These are usually taken right from the first three letters of the city. For example, HOU is the code for Houston, D-E-N is the code for Denver, ATL is the code for Atlanta, and AMS is the code for Amsterdam. Fukuoka Japan falls into this category, and I'll let you figure out what their code is. There is another small category of codes which are holdovers from the days when pilots use the two-letter National Weather Service codes. These airport codes were adapted by just putting the letter X at the end of the

original two-letter code. For example, LAX is for Los Angeles, PDX is for Portland, and PHX is for Phoenix, and they're all based on their original weather service codes. Sioux City, Iowa has the unfortunate code of SUX for this reason. Some codes are based on the area that the airport is in, or based on multiple cities. MSP is for Minneapolis and St. Paul. FLL is for Fort Lauderdale Hollywood, DFW is for Dallas-F-W-W and D-T-W is for Detroit-Wain County. Other airport codes are harder to decipher, but they do make some sense if you know the reason behind it.

CVG is the code for Cincinnati, which at first doesn't make any sense. However, the airport isn't located in Cincinnati, but in Kentucky, and the closest town is Covington, which is what the code is named after. The code, C-I-N, is actually used for Carroll, Iowa. Many codes are named after the airport, not the name of the city. JFK is for John F. Kennedy International, and LGA is for LaGuardia in New York.

CDG is for Charles de Gaul in Paris. Dulles International Airport in Washington has the code IAD, which never really made any sense to me. There is, however, a good reason for it. The code used to be DIA, which was just the initials of the airport. However, it was constantly confused with D.C.A., which was the other Washington airport. So in 1968, they just moved the letters around. And DCA stands for District of Columbia, Arlington. Other airport codes are a holdover from when the airport used to be named something else. O'Hare Airport in Chicago is ORD, which has nothing to do with either the city or the airport name.

ORD comes from the old name of the airport, which was Orchard Field. Likewise, Orlando's airport code is MCO. MCO was the code for McCoy Air Force Base, which is what the airport used to be. The Cahu Louis Airport in Maui has the code OGG, which really makes no sense. However, it's named after Bertrand Jimmy Hogg, who was an aviation pioneer in Hawaii. OGG are just the last three letters in Hogg. New Orleans Airport code is MSY, which stands for Moiseant Stockyards. The name comes from Daredevil Aviator John Moiseant, who died in 1910 after a plane crash on the farm where the airport now stands. There are some very obvious codes that are not assigned to airports. They are used for entire cities when doing searches. CHI is for all of Chicago, NYC is for all of New York,

and L-O-N is for London. If you search these codes, it will find all airports in that city. Likewise, other codes exist for cities with multiple airports, including Moscow, Rio, Rome, Seoul, Jakarta and Buenos Aires. Because every airport is limited to three letters, you get all sorts of combinations. Russia's Bolshoi-Savino Airport code is P-E-E, and Brazil's Pocaldas airport is code P-O-O-O. The Omega Airport in Namibia is OMG, and Lovelock City, Nevada is LOL. No matter how weird the code sounds, there's usually a method behind the madness, and there's some reason, even if it's historical, why it has the airport code it does. Now, there's one final category of airport code that requires extra explaining, because they make absolutely no sense at first glance, but here too there is a reason behind the naming

conventions, and that would be Canadian airports. Toronto's Lester B. Pearson International Airport has the code Y, Y, Z. There are no Y's or Zs to be found anywhere in the name of the city or the airport, nor is there any historical name for the airport which uses those letters. In fact, most major Canadian airport codes start with the letter Y. Montreal is YUL, Vancouver is YVR, Calgary is YYYC, and Ottawa is YOWW. So what's the deal with the letter Y and Canadian airports? Just as with the United States and the development of airport codes, in Canada it has to do with the weather. Pilots needed to know if an airport had a weather station.

In Canada, they used a prefix in front of a two-letter airport code to indicate if they had a weather station or not. The letter Y was used to indicate, yes, they had a weather station. The letter W was used if there was no weather station. Fast forward to 1947 when they codified all the airport codes, and by that time, all the major Canadian airports had weather stations. So they all began with the letter Y. When it came time to select codes, all the Canadian airports stuck with what they were already using. Okay, so that explains why everything begins with a Y. But what about the other two letters. Why is Toronto Y Y, Y, Z? What's with the YZ part? That has to do with telegraph stations which were used by the Canadian National Railway. Each telegraph station

had a two-letter code, which really had nothing to do with the name of the city it was located in. The Malton, Ontario Telegraph Station, was where the airport is located now, and it had the code YZ. Put them all together, you get Y for, yes, there is a weather station, at location YZ. Z. This is basically how all of the first airports in Canada were named, and the convention of using the letter Y just stuck. I'll close by noting that there are three letters that do not appear at the start of any airport code in North America, K, N, and W. The letters K and W are avoided, so there's no confusion with North American radio stations, which all have call signs that begin with those two letters. The letter N is avoided because it's used for U.S. naval bases.

So the takeaway from all of this is that there's always some sort of reason why an airport has the code it does. Sometimes it's really obvious. Sometimes it might be shrouded in history, or sometimes it might be Canadian. Either way, there is always some sort of hidden logic behind the creation of airport codes. The associate producer of Everything Everywhere Daily is Thor Thompson. If you'd like to support the show, please donate over at patreon.com. There is content only available to supporters, merchandise, and even, and opportunities for a show producer credit.

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