Lately I’ve been spending a fair amount of time reading about the history of the airline industry. This was primarily sparked by my research into the history of Lufthansa. That led to my reading of “747: Creating The World’s First Jumbo Jet And Other Adventures From A Life In Aviation” by Joe Sutter, the man who quite single handedly kept the 747 program on track from inception to delivery and beyond (book review coming soon). I wanted to get a good background on the history of the 747 and what better source to learn it from than the Head Engineer who over saw the 747 development from preliminary sketches through to delivery.

As I peeled back the proverbial onion, I came across information that was new to me but had always been a curiosity.

Have you ever wondered what Boeing’s numeric sequence means when it comes to aircraft models? I’m not referring to the 7×7 part of the name, that’s the easy part. I’m referring to the suffix (the -xxx in 7×7-xxx), and specifically the last 2 characters of the suffix.

Have you ever seen information on an aircraft where it is identified as a 747-430? or 747-422? or perhaps 747-436? Obviously, Boeing has only one Boeing 747-400 so what meaning do the last 2 characters in the model’s suffix carry?

I’ve come to discover that it is actually the customer number that Boeing assigns to each of it’s clients. Boeing has been doing this since they assigned customer code 21 to their first airline client, Pan American World Airways (Pan Am). Why 21? My best guess is because Pan Am had ordered 21 Boeing 377 aircraft that entered service in 1949 and this was Pan Am’s first major order from Boeing.

Boeing actually has 5 different sequences that it has used over the years to match aircraft to airline:

The first sequence: 21-99
The second sequence: 01-19
The third sequence: A0-Z9
The fourth sequence: 0A-9Z
The fifth sequence: AA-ZZ

The most interesting part in all of this is when aircraft are sold between carriers/governments/leasing companies, the suffix does not change. An aircraft that was originally delivered to customer 22 that was subsequently sold by customer 22 to customer 30 would still retain its original customer 22 identity. The closest comparison I can draw is the customer number acts as a Maiden Name for an aircraft and stays with her for her entire service life.

After some research and sorting, I’ve come up with the customer list for most Alliance affiliated airlines, as well as for major none-alliance carriers as well (note: if an alliance member is missing, it may mean it has no Boeing Customer number since it may have never ordered an aircraft directly from Boeing):

STAR ALLIANCE: Air Canada: 33, Air China: 9L, Air New Zealand: 19, ANA: 89, Asiana: 8E, Austrian: B8, Continental: 24, Egyptair: 66, Ethiopian: 60, LOT Polish: 9D, Lufthansa: 30, SAS: 83, Singapore Airlines: 12, South African: 44, Swiss: 57, TAM: 2W, TAP Portugal: 82, Thai: D7, Turkish: F2, United: 22, US Airways: B7

ONEWORLD: Alaska: 90, American: 23, British Airways: 36, Cathay Pacific: 67, Iberia: 56, Japan Airlines (JAL): 46, LAN: 16, Malev: 7G, Mexicana: 64, Qantas: 38, Royal Jordanian: D3.

SKYTEAM: Aeroflot: M0, Aeromexico: 52, Air Europa: 5P, Air France: 28, Alitalia: 43, China Airlines: 09, China Eastern: 9P, China Southern: 1B, Czech(CSA) Airlines: 5S, Delta: 32, Kenya Airways: U8, KLM: 06, Korean Air: B5, Tarom: 8J, Vietnam Airlines: 6K.

NOTABLE NON-ALLIANCE AIRLINES: Air India: 37, Aer Lingus 48, El Al: 58, Frontier: 91, Etihad: FX, Emirates: 1H, Virgin Atlantic: 1R, Southwest: H4, AirTran: BD, Air Berlin: 6J, Fedex: S2, RyanAir: AS, EVA Air: 5E, EastJet: 3V