I recently received an email from a reader, Bob S, asking me about aircraft tail numbers. It seemed like a simple topic, but I found myself diving in and learning more than I ever thought I cared to know. It was awesome. The result is a two part series talking about how most carriers in the US pick their registration numbers. Today, we’ll look at the big four US carriers and their subsidiaries. Next time, we’ll look at everyone else.
First, what is a tail number? Every aircraft in the world is registered (possibly excluding some nefarious operations). Just like your car’s license plate, every airplane has a unique identifying combination of letters and numbers which must be displayed on the outside of the airplane. Like a license plate on a car, it can be re-registered during its lifetime. Every country has its own code to begin the tail number. Some, like Canada, which starts with C, makes sense. Others, like the US? Not so much. (Here’s a full list.)
In the US, all tail numbers begin with the letter N. Why? There is actually a pretty fascinating history of the so-called “N Number” that stretches back 100 years. It’s tied to radio call signs and the Navy. Since 1948, all registration numbers in the US have started with N and then been followed by up to 5 additional characters.
With this jumble of numbers and letters, most airlines have opted to give some sort of order to the process. If you know what the order is, then you can glean a fair bit from a registration number alone. But when it comes to the big guys, it gets more complex. A consistent system is tough when you have 1,000 airplanes to register so the biggest carriers have created their own “nose numbers” which are internal designations that are sometimes not tied to the registration number at all. I spoke with Joe Maloy from US Airways (now with American) about how the merger has created some logistical challenges in that regard. Let’s dive in with American first.
American has some old airplanes, and because of that, it has a lot of different registration formats that have been used over the years. Now with the merger, the airline is trying to create a standard nose number system and then tie the tail numbers as closely as possible going forward (but that will be tough). Thanks to inflexible technology systems, those nose numbers have to have 3 characters (no more, no less). The plan going forward is to have the Boeing aircraft start with a fleet number and then be followed by two characters. The 737-800 above is 3KS (as you can see in small type), for example. The Airbus fleet will also be three characters but it will be all digits. The first A319, for example, is 001 where 0 is the A319 fleet number for American’s deliveries. This helps explain why American’s pre-merger A319 registrations are so goofy.
The first American A319, N8001N seems straightforward. That’s fleet number 0, aircraft number 01. But the second one is N9002U. Then the third one falls off the rails with N93003. Looking at the full list, you can see that they just picked random numbers and letters that would allow them to stuff the nose number in there somewhere. There isn’t much of a pattern. That changes with the other fleets, however.
Please note that the suffix you see on these, sometimes AA or AN, won’t be the same for every airplane. Sometimes, the preferred suffix won’t be available so they use a backup like AM or even just A. And there are always a couple random ones that don’t fit the mold. Also, when you look at the formats, note that x is a number and z is a letter. If you see some overlap, that’s because old fleets (MD-80/757/767) are being phased out in favor of newer ones, so they will start to replace each other.
- N4xxAA (nose number 4xx)
- N7x4xx (nose number 4xx)
- N5xxAA (nose number 5xx)
- Nxx5xx (nose number 5xx)
- N7x5xx (nose number 5xx)
- N75xxx (nose number 5xx)
- N9xxxx (former TWA aircraft) (nose number 4zz)
- N9xxAN first (nose number 3zz)
- then N8xxNN (nose number 3zz)
- currently N9xxNN (nose number 3zz)
- N1xxNN (nose number 783-799 for A321T, 850-999 for others)
- N6xxAA (nose number 5zz)
- N1xxAN (nose number 5zz)
- N3xxAA (nose number 3xx)
- N393xx (nose number 3xx)
- N7xxAN (xx = 50 or higher) (nose number 7zz)
- N7xxAN (xx = 49 or lower) (nose number 7zz)
On the US Airways side, it’s a mix of both America West and US Airways aircraft. You can figure out which are which very easily. If it ends in AW, that means it was an America West airplane originally. The nose numbers match the tail numbers here for the most part, and the numbers you see below are the ones that will exist in the new combined fleet.
- Embraer 190
- N9xxUW (xx = 43 to 67) (nose number 9xx carved out of AA A321 range)
- N7xxUW or US (CFM-powered) (nose number 7xx)
- N8xxAW (IAE-powered) (nose number 8xx)
- N1xxUW or US (CFM-powered) (xx = 102-128) (nose number 1xx)
- N6xxAW (IAE-powered) (nose number 6xx)
- N1xxUW or US (CFM-powered) (xx = 150 and higher) (nose number 1xx)
- N5xxUW or AY (IAE-powered) (nose number 5xx)
- N9xxUY (post-American merger IAE-powered) (nose number 9xx)
- N2xxUW (xx = 00 to 07) (nose number 2xx)
- N9xxUW (xx = 35 to 42) (nose number 9xx)
- N9xxAW (xx = 01 to 10) (nose number 9xx)
- N2xxAY (xx = 48 to 56) (nose number 2xx)
- N2xxAY (xx = 70 and higher) (nose number 2xx)
There are a few special registrations in the US Airways fleet. When the airline painted retro liveries to honor its predecessor airlines, it went all out and re-registered the airplanes to fit.
- N475VJ: Allegheny retro colors (the VJ stands for VistaJet)
- N742PS: PSA retro colors
- N744P: Piedmont retro colors
American now has three wholly-owned regionals as well.
- Dash 8-100
- N8xxEX (former Allegheny aircraft)
- Dash 8-100
- N9xxHA (former Henson aircraft)
- Dash 8-300
- N2xxPS or JS
You can see that even the regionals have begun adopting American’s scheme. The new CRJ-900 deliveries at PSA fit with American’s registration system.
If you want a maddening exercise, try to figure out how Delta registers its 757 and 767 fleets. There’s such a mish-mash of origins here that it can be tough. But that doesn’t stop me from trying. As always, there can be minor variations here if they can’t get the exact registration they want for each aircraft. The aircraft ending in US and NW are Northwest airplanes. For whatever reason, Northwest previously used US as it suffix. I’ve asked Delta for info on where the NB came from (also ex-Northwest), but I haven’t heard back. [Updated: As mentioned in the comments, NB stands for Norwest Bank, the original owner of the Northwest A319s.) I’ll have a few notes down below.
- N9xxAT (former AirTran aircraft)
- N3xxNB (former Northwest aircraft)
- N3xxDQ or DE
- N9xxDE or DL
- N9xxDA or DN
- N3xxUS (xx = 26 or lower) (former Northwest aircraft)
- N3xxNW (xx = 27 or higher) (former Northwest aircraft)
- N3xxDA or DN
- N8xxDN (xx = 859 and lower)
- N5xxUS (xx = 549 and lower) (former Northwest aircraft)
- N5xxNW (xx = 550 to 580) (former Northwest aircraft)
- N6xxDL or DA or DN
- N67xxx (former Song aircraft)
- N7xxTW (former TWA aircraft)
- N7xxAT (former ATA aircraft)
- N5xxNW (xx = 581 and higher) (former Northwest aircraft)
- N1xxDL (xx = 129 to 149)
- N1xxDL (xx = 150 to 159) (former Gulf Air aircraft)
- N1xxDN (xx = 169 to 199)
- N8xxNW (former Northwest aircraft)
- N8xxDA (xx = 860 and higher)
Quite a list, huh? The one thing that stood out for me was the 767-400. Why the heck is there an MH suffix on that? I’m told by someone outside the company that it stands for Mullin Holdings. That’s right, you can thank former CEO Leo Mullin for that little ridiculousness. I haven’t been able to get the airline to confirm that.
As for Delta’s wholly-owned regional, it’s a mish-mash of previously-owned airplanes that haven’t been re-registered.
- N6xxXJ (former Mesaba aircraft)
- N6xxLR (former Mesa aircraft)
- N9xxXJ (former Mesaba aircraft)
Southwest by far has the most fun with aircraft registrations. Fortunately, I was able to speak with the airline’s guru on this matter, Richard West. Richard has written about some of this on the Southwest blog, but here’s as complete a list as I could come up with.
The original methodology for registrations was NxxxSW. If SW wasn’t available, they’d use SA (Southwest Airlines), WN (the airline’s two letter code) or LV (for the LoVe airline). A few of the 737-700s have GS at the end. That stands for Gene Stewart, the 737-700 project director for the airline. This standard gave us the following registrations:
- N5xxSW (xx = 49 and lower)
- N5xxSW (xx = 50 and higher)
As Southwest continued to grow, the time came to change the standard to use 4 digits and then a single letter at the end in order to have more options. The 737-800 fleet uses this across the board. The AirTran 737-700s and any new 737-700s that come into the fleet will follow this standard as well.
- N77xxz (former AirTran aircraft and new additions)
- 737-800 ETOPS
With all that being said, Southwest has a ton of special registrations meant to honor various people and groups.
- N216WR and N217JC: two employees who were killed in a general aviation crash
- N289CT: Charles Taylor, 1st airplane mechanic under the Wright brothers
- N500WR: William Rogers, the Southwest representative at Boeing. This was his 500th delivery.
- N711HK: Herb Kelleher, former CEO (remains in the original colors)
- N714CB: Colleen Barrett, former President (remains in the original colors)
- N737JW: Jim Wimberley, former COO
- N738CB: Colleen Barrett, former President (again)
- N739GB: Gary Barron, former EVP and COO
- N761RR: Ron Ricks, EVP
- N777QC: Quality Control department, they didn’t have many options on the 777 aircraft, so this stuck
- N797MX: Maintenance department, similar story
These guys clearly put a lot of thought into this, and I like it.
Talk about a tale of two airlines. Pre-merger United had just about the cleanest system possible for such a big airline. Pre-merger Continental, not so much? Continental went with an N##xxx configuration. What are the pound signs? Those are numbers like the “x,” but spokesperson Rahsaan Johnson confirmed that, with limited exception, those two digits are completely random while the last three are aircraft numbers. Go figure. (If you’re wondering which ones aren’t random, Rahsaan mentioned N77014 where that was meant to tie to the Peter Max 777 it was.)
- N##7xx (xx = 49 and lower) (former Continental aircraft)
- N##4xx (xx = 12 and lower)
- N##4xx (xx = 13 and higher)
- N##8xx (xx = 50 and lower)
- N##8xx (xx = 51 and higher)
- N##0xx (xx = 51 and higher)
- N##9xx (xx = 949 and lower)
- N–9xx (xx = 950 and higher)
- N##0xx (xx = 50 and lower)
By far the big four carriers are the ones who make life the most complex. Next time, we’ll look at the smaller legacy carriers, the low cost carriers, and the regionals.
great summary, Brett. Thanks for compiling. I’m keeping this for future reference.
All I can add is that the former NWA birds with NB in the tail number are referring to Norwest Bank, who owned the lease. I think they are now part of US Bank.
Norwest bought Wells Fargo and decided to use the Wells Fargo mark.
Thanks for the great summary! I always had a rough idea of how tail numbers worked, but this fills in a lot of things I didn’t know.
As for DL, too bad they retired all the DC-9’s. If they were still flying, you could have talked about the old North Central days, with those birds and their NC tail numbers.
And Brad, Norwest became part of Wells Fargo – the other big bank in Minneapolis
My understanding is that Norwest bought Wells Fargo, kept Well’s name and moved the new headquarters to San Francisco with Norwest (mostly) management. This was after the BofA merger of equals (i.e., takeover) by Nationsbank. The Nationsbank
management was not pleased when analysis showed that the BofA name was MUCH preferred by various focus groups so that name prevailed. (Disclosure: I worked for BofA for 35 years.)
Now we know why the airline industry is so messed up, they can’t even put numbers on airplanes in a simple way…..LOL
One of the byproducts with N designations is the fact that Newark is EWR & not NWK or something similar. Didn’t realize the tie in to tail numbers though.
Airport codes that start with letter N are Naval airstations, so its
EWR and not NWK.
What a crazy system! One of my favorite tail numbers of all time was EI CHD with Morris Air aka “El Chud”. It was purported to haunted and it had quite the wild past to support the claim – look it up! I had been on the plane many times during my Morris Air days and used to see it quite often @ Southwest. They changed the tail number to N386SW I think – not sure if it’s still flying these days.
If you do look up the story, I can tell you their really was a dent in the flight control panel which could have been from a bullet ricochet.
Update – it changed to N698SW.
all i could find is that it sold new to CPAir…then went to VASP where there was an attempted hi-jack with one dead on board…now at southwest
In your trip reports, you usually list the tail number of the plane you are on. I have tried to check for it before boarding a plane, but usually do not see. Any tips on how to get it? Thanks.
Faithful reader – Depending on the airline, I find it’s usually easiest to find it from the terminal. Look out the window and you should see the tail number painted. If you don’t, you should definitely be able to see the nose number on the nosegear door. You can put that in Google and usually get that translated. On the airplane, above the forward doors, you’ll usually see a registration certificate from the FAA that has it. Some airlines like Southwest make life easy and put it on a plaque that you’ll see as you walk in. Otherwise, you can always ask the crew before or after the flight. During flight you could ask a flight attendant to ask for you, though you might get a funny look.
Thank you for that interesting research. it did remind me when we were on a flight that had mechanical difficulties before leaving the gate. The captain got on the intercom with a status report and ended by saying that if the repair couldn’t be fixed, we would have to “change tails.” One of the passengers was quite clearly distressed by that. Eventually the captain got back on to explain that “changing tails” meant taking a different plane and not actually removing the tail section from ours and replacing it with another tail section, as the distraught passenger had assumed. The poor guy did not want to fly on a plane that had a recently replaced (presumably at the gate) tail section.
As a old time NWA flyer, I was told by one of their maintenance managers that the designation US came from the lienholder of the aircraft which was US Bancorp at the time. If you pull the N-numbers up some of them still show that lienholder. Just my 2 cents. Don’t know how true.
many people see the ex-nwa planes with the US at the end and think they were once owned by USair
I had thought that NW using “US” predated significantly their various financial brough-ha-has, like back to the time when Alleghany was using “VJ” for “VistaJet” (and advertising the fact heavily), but I haven’t been able to confirm that via some quick googling.
I thought I read somewhere that the US designation was started because Donald Nyrop wanted to change the name to US Airlines. But US Bank being the lien holder makes more sense.
Great list, Brett! Love all the detail and Southwest’s creativity in particular. I actually think UA and CO are some of the easiest nomenclatures to understand from a spotters perspective since there are zero exceptions to the rules. However, within fleet types for AA and DL, the registrations are much more variable.
One slight addition: CO’s 737-900s are ships 401-412 and the ERs start from 413 and up.
I remembered flying on a WN 737 (forgot which variant) years ago out of BUR with AA as the last two digits. Did they changed the registration on that aircraft?
Also, for UA 737-900, 4xx below 50 is PMCO. Currently, all 4xx are s-CO. 8xx are newly delivered post-merger, assigned to s-UA.
That would have been an old AirCal 737-300 Southwest got by way of AA.
ptahcha – To add to what Brandon says, those are either all out of the fleet or they’ve been re-registered by now. But I don’t see any active NxxxAA 737-300s anymore with Southwest.
Great! Thanks for your work.
A couple of years back, waiting for my flight–I can’t remember at which airport, I noticed a US-flag airline’s aircraft parked at the gate with a “C-_____” registration number on it. I’m sure this aircraft was there to fly in a purely, domestic, US city-pair service, but…always possible, there was some reason why a “C-” registered aircraft was being used.
I’m somewhat aware of the international dispute (now resolved, I understand) of the Air Canada/NHL charters, but can any traveler be reasonably assured that for his or her purely, domestic, US city-pair travel, he or she will be transported only on a US-registered (N-_____) aircraft?
Is there some requirement that US-flag airlines that operate purely domestic, US city-pair service do so only with US-registered “N-” aircraft? Like maybe there would be some type of difference in safety regulation/nationality crewing/taxation dependent on where the aircraft was registered?
Anything like ships which have “flags-of-convenience” registration, or like why it seems at least half of the semi-trailers in tractor-trailer service here in the East seem to have state of Maine license plates?
JayB – No rule about that at all. As someone else mentioned, Morris Air used to operate EI-CHD. That was, I assume, an airplane that was owned by an Irish lessor and then leased to a US carrier. But this isn’t a flag of convenience thing. I believe you have to register the aircraft in the country of the owner or on a long term lease, I assume it could be in the country of the operator.
If you have the tail number of an aircraft and want to find out all sorts of details about the plane, go to http://registry.faa.gov/aircraftinquiry/NNum_Inquiry.aspx
I’ve also been curious about why Avianca has N* numbers for their aircraft, does Colombia not register aircraft?
Rob – Great question. I can only assume it’s somehow better for them tax-wise so they set up a subsidiary in the US to actually own the airplanes. But I don’t know for sure.
colombia is HK- and then 1 to 4 digits…by the number you can tell roughly when or how old the plane is, avianca had a 747-200 registered HK-2000…today hk goes up to the 5000 range..N numbers are temporary “tag” numbers…
N249PQ and below are old Pinnacle planes that went to ExpressJet. Anything higher than that is an Endeavour-Delta plane. You will see a nose number of 15(XXX) on those. Additionally, I’m sure the LR’s also went to ExpressJet. I haven’t seen a Endeavour 900 that hasn’t been an XJ or high PQ number in months.
Adam – I’ll reflect that PQ airplanes when I do ExpressJet on the next post, but yeah, these guys all swap airplanes around. As for the CRJ-900s, I show Endeavor still flying N600/601/602/604/605LR.
3 out 6 planes owned by jimmy buffett ends in JB
Corsair, a French airline that seems to do primarily leisure destination flying, has some fun registrations on their aircraft. They have three 747s: F-HSUN, F-HSEA, and F-GTUI (I think they’re owned by TUI Group). They had, at one time, a 747 registered as F-GSEX to go along with the Sun and Sea. They also have A330-300s registered F-HSKY and F-HZEN, as well as a couple of A330-200s with registrations that don’t seem to have any special significance (HCAT and HBIL).
There’s probably much more potential for “vanity” registrations for aircraft registered in countries with purely alphabetical registrations.
BWIA – West Indies Airways B737-800 fleet registrations reflected the 3 letter destination code i.e 9Y-KIN (Kingston), 9Y-BGI (Barbados), etc. Also Virgin Atlantic had some interesting registrations. Excellent website Mr. Crankyflier !!
Thanks to everyone for your updates. I usually don’t update old posts, but in this case I absolutely want to make sure it’s as accurate as possible so I’ve made changes. I went and removed “former Continental aircraft” from all these because it’s pretty obvious what is and what isn’t. No need to muddy the water. But please do keep sending your updates.
I use to work for frontier and there end numbers were purpose presented on the aircraft that was acquired prior to republic take over.
N8xx (and higher)
N9xx (and higher)
N2xx (and higher)
the exception was some A320 aircraft that was acquired from USA3000 and other used aircraft that came into the system there afterwards. very interesting blog I really like it. sure do miss working for the airline industry but after being apart of the outstation worker furlough but it was good while it lasted.
In the words of Mr. Spock – fascinating. Thanks for today’s post, Cranky. You certainly kept this travel geek entertained on the train ride to work today.
United’s is sorta nice because you can tell if the airplane has Channel 9 so you can ask for it by seeing if you can see the tail number well at least with the combined 757 777 and 767 fleets.
Nice article…For registration about indian aircraft you can check at http://www.dgca.nic.in/caris/know_regn.asp
This is an excellent article and shows lots of research. I like the fact you call them “tail numbers” although “registration” is a better term since other countries use an all-alpha system. I simply detest the term “N-number” since that only refers to U.S. registrations which, as you point out, can contain letters.
While I cannot reference the source, I seem to recall reading that the N8xxMH registration on the 767-400 had nothing to do with Leo Mullin. The article stated that the registration was a temporary one given by the FAA to Boeing while the aircraft was in pre-delivery flight testing. The story goes on to say that, for some unknown reason, Delta didn’t want to take the time to change the registrations to match their numbering system and just left it on the plane.
Jonathan – Well, that might be possible as well. I’ve reached out to Delta multiple times on this one, and unfortunately, they have yet to dig up an actual answer.
Just came back to New York from Nice, France flying on a Delta 767-400ER. While boarding had a nice chat with a senior Delta Captain. Mentioned the “MH” ? and he came back quickly with with the 411. Since he has been flying 764’s he also was curious. Story goes, plane was in the final stages of delivery and the man in charge of registrations, a man named “Mike Haynes” needed more time to sequence the numbers. Boeing/Delta said we need it right now. So he just added his own initials.
Close, but his name was Mark Hanna and was paralegal representing Delta when they needed 50 consecutive tail numbers and didn’t care what the suffix was. After trying all the sequences with DA, DL, and DN, I gave up and tried my own initials…..MH.
So many answers to reg. questions, thanks for such a well-researched article. I thought it interesting that some carriers recycled old registrations for newer airplanes. For example, Pan Am’s DC-7C tail numbers wound up on 747s, and American’s DC-7s were resurrected for its 767s, ditto old 707/720 numbers turned up on MD-80s.
Thank you for the detail research. I have recorded the tail number of every aircraft I have ridden in since 1957. When I retired from the USAF I went to work for United Airlines and found their numbering system to be very straight forward but found other airlines’ systems to be confusing. After the merger I have been frustrated with Continental’s numbering system and thank you for clarifying it for me. I am also frustrated with their new location of ‘tail numbers’ because from the gate they are often hidden by the wing. I have received many strange looks from Flight Attendants when I ask them for the ‘tail or N or registration number’. They question why I want to know like I am a subversive. When I try to find the FAA Certificate it sometimes is on the inside of the cockpit door so it is only available before and after the flight when people are lined up behind me and are annoyed when I stop to read the fine print.
Just a couple of notes. For the AA ex TWA MD80’s, the fleet number naming convention is 4zz to differentiate from the 4xx series of original AA MD80’s. The remaining TWA MD80’s start with 4Wz, 4Xz and 4Yz….so for example N984TW is fleet number 4YZ
Learjet1969 – Awesome, thanks for this. I’ve updated the post.
One “airline” that has no tail numbers or markings of any kind are the 737’s that shuttle workers from Las Vegas to Area 51. They fly over my house several times a day. It’s a white plane with an orange stripe down the side and that’s it. They go by the code name “Janet”. I’m not sure if they officially exist.
I can explain the “MH” suffix for the Delta 767 aircraft. It has nothing to do with Mullin Holdings, but a young paralegal working for a law firm in OKC which represents Delta with FAA matters. Delta had requested 50 consecutive tail numbers for their new deliveries and did not care what the trailing characters were. Having a difficult time locating 50 consecutive n-numbers ending in DA, DL, or DN was proving futile, so he decided to try his initials “MH” and 50 consecutive n-numbers were found! Not as fancy as you probably would have liked, but it’s the truth!
A lot of misinformation in this article. Nose numbers can be anything that the owners want, (no min or max)
VJ does not mean Vista Jet
You will always hear tales about Janet airlines (that flies employees of Area 51 to work) some say there is no ”N” number, that’s a lie. They have a secret code, another lie, (each carrier has its own ”different” code) just saying