I recently shared the strange story of how Baltimore’s Friendship Airport (“BAL”) became BWI even though that code was already taken by Bewani, Papua New Guinea.
A lot of aviation codes have unique histories. Some of them are obvious. For instance United Airlines is UA, American Airlines is AA, and Delta is DL. Continental Airlines was CO and Northwest Airlines NW.
Southwest Airlines couldn’t have SW — that belonged to Seaborn World at the time (it’s now Air Namibia). So they took WN which approximates Western and ultimately works nicely because it can be said to stand for We’re Nuts! Although sadly Southwest no longer serves peanuts.
Lore is that Spirit Airlines’ NK stands for ‘Ned’s Kids’ after airline founder Ned Homfeld who had an especially close relationship with his employees. In fact I’m fairly sure that nickname came after the two letter code. On the other hand their ICAO code is ‘NKS’ which lends some support to the Ned’s Kids notion.
The Flight Detective tracks down the source for some less obvious two letter codes.
- AY: Finnair is Aero Yhtiö or airline company.
- BW: Caribbean Airlines dates to BWIA or British West Indies Airways.
- EI: Aer Lingus’ code stands for Éire which means Ireland.
- MS: EgyptAir began as Misr Airwork.
- NH: Japan’s All Nippon Airways began as Nippon Helicopters.
- OK: Czech Airlines uses this code, deriving from the radio call sign ‘OK’ assigned to then-Czechoslovakia in 1927.
- RO: TAROM is the Romanian carrier or ‘RO’.
- SN: Predecessor of Brussels Airlines was once Sabena.
- SU: Aeroflot is ‘Soviet Union’. By the way Soviet Union diplomatic license plates in the US were ‘FC’ in the mid-1980s for “f- commies.” (Here’s that story.)
I’ve always thought Alaska Airlines (AS) should have been AK, but that’s now taken by AirAsia.