What's in an N-number?
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Whatï¿½s in an N-Number?
A         recent query to the American Aviation Historical Society (www.aahs-online.org)         asked the question, "What is the origin of the "N" in         United States civil aircraft registrations?"  How did the U.S. end up with "N" instead of "US," or some other designation, as the prefix on our civilian         aircraft?  After all, Sweden         has "SE", Great Britain uses "G", Germany has "D" (Deutschland), and France is "F".  And while we are considering this question, where do the C, L, R,         X and S prefix designations (NC12345, NX123B, NS123) as seen on some         aircraft come from? 
1919         Commission Internationale de Navigation Aerienne 
     The         origins of the N in the U.S. registration can be traced back to the         Commission Internationale de Navigation Aerienne (CINA - the Convention         for the Regulation of Air Navigation) established as part of the Paris         Peace Conference immediately following World War I. A part of this         conference was the adoption of the Convention for the Regulation of         Air Navigation that laid the foundation of the system of         international aircraft identification still in use today.  In these proceedings, the first letter(s) of the identification         designating national origin are set as in the examples described above.  Each major participating country was allowed a single identifying         letter and to specify their own designation letter.  The U.S. delegation was allocated "N."    
The convention stated that:
"The           nationality mark shall be represented by capital letters in Roman           characters. The registration mark shall be represented by a group of four capital letters; each group shall contain at least one vowel, and           for this purpose the letter Y shall be considered a vowel. The           complete group of five letters shall be used as a call sign for the           particular aircraft in making or receiving signals by wireless           telegraphy or other methods of communication, except when opening           up communications by means of visual signals."
The nationality and registration marks are assigned in accordance with         Table 1. 
       While         the exact rationale for selecting the letter "N" has not been         preserved, there are a number of stories as to why ï¿½Nï¿½ was chosen.  Some might be classified as "wivesï¿½ tales," others         seem to have a grain of truth to them. Though none have been         substantiated, here are a few reasons that have been uncovered. 
Table 1.
Charles         Lindberghï¿½s Spirit of St. Louis displays         an X registration number         on the Ryan NYP (New York - Paris) indicating that         it was registered in the Experimental category         in April 1927. As the         aircraft was not a production design, the NX-211registration would have         been consistent with the regulations. The         problem is that the use of X for Experimental was not officially adopted         until 1929! (Photo from the Don Hall collection)
This Grumman         TBM-3E Avenger seen         in Palm Springs in 2001, still carries its original Limited NL registration, even though         the use of the L was         dropped in 1948. (Photo from C.H. Hamilton collection)
As do many         aircraft from the Golden Age of flying, this Waco SRE, s/n 5153, NC1252W         seen at the 1995 EAA Convention in Oshkosh, Wis., still sports an NC registration number. The CAA dropped the use of the C, L, R, and X registration identifiers in 1948, replacing all but the C with         cockpit placards. (Photo by Al Hansen)
Why "N" Version 1
       As early as 1914, states         began to license airplanes based in their states.  This was partly motivated by the prospects of increasing the         state's coffers through the associated licensing fees with public         justification being easy identification of aircraft being operated in a         way that put life and property at risk.  States pursuing this aircraft licensing direction tended to         follow their existing licensing practices for personal watercraft.  Maryland was the first state to enact aircraft licensing         requirements sometime in late 1914.  The first aircraft license issued was MAR-1.  Other states soon followed and generally used some sort of         shortened alpha character followed by numbers.
      U.S. delegates attending the Paris         Conference and working on the Convention for the Regulation of Air         Navigation were aware of the individual state's licensing efforts.  In an attempt to avoid confusion with the display of a required         state identification number, this group appears to have requested the         letter N that it deemed would stand for the national number. 
       As to the issue of avoiding confusion?  A quick check of state names shows that states with names         beginning in N are among the most prolific.  If we assume that these states would use N as part of their state         registration identifier, then the selection of N for a national         identifier would only add to the confusion.  With Utah being the only state beginning with ï¿½U,ï¿½ this would         have been a more logical choice based on this rationale.  Furthermore, this letter was not assigned at the 1919 conference,         so was readily available. 
Why "N" Version 2
      The delegates, being very         patriotic selected the letter ï¿½Nï¿½ in recognition of the thirteen         original states that formed the U.S.  ï¿½Nï¿½ was selected because it is the thirteenth letter in the         alphabet.
       Now one can just imagine a bunch of         bureaucrats sitting around a table - probably after having consumed         copious amounts of alcohol - coming up with this rationale.  The only problem is that the letter ï¿½Nï¿½ is the fourteenth         letter in the alphabet.  So         what letter was excluded?  Or,         did these individuals just not have a firm grip on the alphabet.  This version is probably best categorized as an interesting story         but not the real reason ï¿½Nï¿½ was selected. 
Why "N" Version 3
      This version is based on current         events of the time.  The four U.S. Navy Curtiss flying boats (designated NC-1 thru         NC-4) set out on May 14, 1919, to begin the first crossing of the         Atlantic by an aircraft.  As         we know, only NC-4 successfully completed this crossing, eventually         arriving in Plymouth, England, on May 27, 1919.  This first flight (albeit not nonstop) preceded the nonstop         flight by Alcock and Brown by almost a month.  The flight was still fresh on everyone's mind at the time the         first international aviation congress convened and our delegation         selected ï¿½Nï¿½ in commemoration of this first flight.
       This story sounds logical,         particularly if none of the U.S. delegates were Navy types and were         unaware that the ï¿½Nï¿½ designation for the NC-4 really stood for Navy.  This story like the others has not been substantiated. 
Why "N" Version 4
       The letter ï¿½Nï¿½ was         selected to stand for North America, with ï¿½Cï¿½ being assigned to         Central America and ï¿½Sï¿½ for South America.  The U.S. ended up exclusively with ï¿½Nï¿½ because Canada was         part of the British Empire in 1919 and the registration convention for         such colonies was to use the British designation in combination with an         assigned letter.  Canada's         designation was G-Cxxx which was changed later.  Along with this story goes the postulation that the letters "US" or "USA" could not be selected because the U.S.         was one of the five "super" powers designated to have only a         single registration prefix.  The letter ï¿½Uï¿½ was unacceptable for unknown reasons, even         though it was not assigned to any country during the 1919 convention.
       The problem with this version is         that it is rife with inconsistencies.  As we can see in Table 1, the list of assigned registration         letters to all the 1919 participants, Brazil was given P-Bxxx and Panama         S-Pxxx, neither of which is consistent with this theory.  In fact, a quick scan will show you other inconsistencies as         well.  Furthermore, Great         Britain was quite content with the single letter ï¿½G;ï¿½ so the U.S.         could have just as easily accepted ï¿½U.ï¿½ 
 
Why "N" Version 5
       The most probable reason the         U.S. was allocated ï¿½Nï¿½ for its national registration mark comes from         existing regulations of wireless communications in place in 1919.  The International Telecommunications Union (ITU, formed in the         late 1800s to provide international standards in telecommunications and         still going strong today) held its first International Wireless         Telegraph Conference in Berlin in 1906.  Here the first Service Regulations were established for         governing international radiotelegraphic communications.  It was at this conference that S-O-S was adopted as the         international radio distress call.  By 1912, the proliferation of wireless radio stations, both land         and ship based, had created chaos in the airways as each base (or         country) was creating their own call-signs for identification leading to         the potential for call-sign duplication.  In 1912 at the London International Radiotelegraphic Conference,         the Service Regulations were expanded to include a protocol for         international radio call-signs.  In         short, the following identifiers where assigned to major countries: 
        G - Great Britain
              J - Japan
              N, KDA-KZZ, Wxx - United States 
The         reason "N" was assigned to the U.S. was in recognition of the         industry leading development and deployment of wireless communications         by the U.S. Navy that had been using "N" as the prefix to its         station call-sign identifiers since 1909.  
      Obviously, at this point in history         (1912) aircraft were barely capable of carrying a pilot and passenger,         much less a bulky wireless set.  By 1919, when the CINA met, both aviation and wireless         technology had made great advances - in part due to developments         associated with WWI.  Aircraft         were now capable of carrying wireless communication gear and the         practice of including such gear was increasing.  As an international protocol for identifying wireless stations         already existed, the CINA simply adopted a subset of the ITU call-sign         identifiers for consistency.  Support         of this can be seen in the CINA specifications quoted above that state         aircraft are to use their registration number in wireless communications         with base stations.  By combining the ITU standards into the registration marks,         the CINA was simply assuring clarity in wireless communication on an         international basis while avoiding unnecessary redundancy.
       Support for this version is found         in Aviation magazine dated June 11, 1923 (page 639) that states: 
"Nationality         Mark of American Aircraft: Aviation reported some time ago on the         strength of a Norwegian government decree published in "Machrichten         fur Luftfahrer" (the German air department bulletin) that Norway         had adopted the letter "N" as its nationality mark. As this         letter had previously been allotted to the United States as its aircraft         nationality mark, it was editorially suggested that when this country         becomes a party to the International Air Convention, the American         representatives should ask to have the letter "W" allotted as         our aircraft nationality mark. It was pointed out that as the letter "W" was one of the international call letters allotted the         United States - as is "N" - such a choice would be         eminently practical as well as an act of homage to the Wright brothers.         The National Aeronautic Association of U.S.A. now announces on the         authority of the Controller General of Civil Aviation in Canada that at         the third session of the International Commission for Air Navigation,         the letter "E" was granted to Norway as that country's         nationality mark, with the letter "N" as the first letter of         the registration mark. The letter "N" therefore remains the         nationality mark allotted to United States civil aircraft." [Norway         never adopted the E-Nxxx allotted to it, but later standardized on         LN-xxxx]
This         article tends to support the supposition that the CINA adopted the ITU         call-sign identifications as both ï¿½Nï¿½ and ï¿½Wï¿½ appear to have         been allocated to the U.S. The article also implies that we quite easily         could have ended up with our aircraft registration numbers beginning         with ï¿½Wï¿½, though not in honor of the Wright brothers.
       Unfortunately, the U.S. Department         of Commerce Bureau of Navigation (responsible of administering wireless         radio communications from 1911-1927 didn't get with the program.  They continued to require separate radio licenses in planes so         equipped. During the 1920s and 1930s, they even issued separate         call-sign identifiers to these stations beginning with the letter K. For         example, in 1937 Amelia Earhartï¿½s call-sign on her Lockheed 10E,         NR16020, was KAHQQ.  It was         not until the late 1940s that the practice of assigning call-signs was         discontinued, though they still required a radio license for both the         radio transmitter and the operator.
       So, we can probably thank,         indirectly, the U.S. Navy for the "N" in the U.S. aircraft         registration, as some have postulated, but it wasn't because of the         transatlantic crossing of the Navy-Curtiss flying boats.
"N" Mark History
       Interestingly enough, the         U.S. Government would not ratify the 1919 accord. It wasn't until 1926         that the issue of national aircraft registration had reached a point of         visibility that forced Congress to finally act in the form of the Air         Commerce Act of 1926.  In         the meantime, in 1921, the National Aircraft Underwriters Association, a         service organization for the insurance industry, attempted to establish         a five-letter licensing code.  The         code included the prefix letter ï¿½Nï¿½ followed by four alpha         characters (N-ABCD) in a manner similar to that currently used by a         number of countries including Great Britain (G-ABCD).  This system was purely voluntary and had no governmental backing         or support.  Due to a lack of support from either the government or by         manufacturers, only 33 planes were registered by the end of 1922.  The system had been abandoned by 1925.  While the exact number of aircraft registered with this system         probably never exceeded 50, there are aircraft from this period that         appeared with registrations in this form.
      In May 1926, the Federal Government finally got its act together with         its first attempt at organization via the Air Commerce Act that         became effective in January 1, 1927.  This system essentially implemented the 1919 Paris Convention         relative to national identification, but deviated in that the         identifying marks would be numbers 0000 through 9999 rather than four         Roman letters.  It further extended the system by including a classification         letter to denote commercial (C), State (S), or private (P).  The letter ï¿½Cï¿½ was used to designate approved (airworthy)         aircraft used in commerce and for airmail.  The ï¿½Sï¿½ included all state and federal government owned and         operated aircraft. The ï¿½Pï¿½ designation was created to sort out         private aircraft from the ï¿½Cï¿½ and ï¿½Sï¿½ types, but this lasted         only until March 1927.  The         need for the ï¿½Pï¿½ designation was obviated by most states requiring         aircraft operating within their boundaries to bear a ï¿½Cï¿½ number.  Interestingly enough, Oregon where much flying activity took         place, was one of the few exceptions to this requirement.  From the implementation of the Air Commerce Act until the         late 1930s, the aircraft registration actually consisted of two parts         ï¿½ the Identification Mark Assignment number, and if approved         for any form of formal license, the prefixes. A limit of four numbers         was deemed adequate at the time to handle all possible aircraft         registrations - after all, who in 1926 could imagine an aircraft         population numbering more than 10,000?  
       By November 10, 1928, less than two         years from the time the DoC started issuing licenses and Identification         Mark Assignments, the 10,000th number had been issued and the DoC         ruled that, since issuance of numbers above 9,999 would "unnecessarily incumber the wings of planes, a reissue has been         started with the addition of a capital letter "E" following         the numbers." 
       A provision in the 1926 Act also         allowed for identification of aircraft that did not meet minimum         airworthiness requirements. These aircraft were termed Identified         Aircraft and were to wear Identification Mark Assignment (IMA)         numbers, usually without the N.  It         was possible to register such aircraft under this provision up until         March 1939.
       The National Air and Space Museum (NASM)         has an on-going Pre-1946 U.S. Civil Aircraft Register Project.  In their research of the Department of Commerce records, the         earliest document found specifically referring to aircraft markings in a         registration file was dated April 20, 1927, when the Department of         Commerce sent a letter to the Ludington Exhibition Co., Inc., in         Philadelphia.  The letter         states, in part,
Enclosed         herewith is your "Identification Mark Assignment" together         with a metal identification plate. The identification mark which has         been assigned to you must be prominently displayed on your aircraft in         accordance with the provisions of Section 41 of the Air Commerce         Regulations. The metal plate must be permanently affixed to the fuselage         in a prominent place, in order that it may be readily inspected. No         letter or other mark or symbol of any kind shall immediately precede or         follow the identification mark thus displayed on your aircraft. 
The         first commercial aircraft license issued in the United States was C-26,         issued to Wendrell Pavey of Madison & Edwards Roads, Cincinnati,         Ohio, for a Standard J-1. At this point in time, the Department of         Commerce was actually issuing metal plates with both the IMA and         Manufacturers Serial Numbers (or substitute numbers, if none existed),         although this practice quickly came to an end, and the CAA required         manufacturers or builders to affix permanent data plates.
 The requirement for the display of the ï¿½Nï¿½ portion of the         identification number was only required on aircraft being operated         internationally.  If the         aircraft was locally based and operated, it was only required to display         the ï¿½Cï¿½, ï¿½Sï¿½ or ï¿½Pï¿½ number. It is possible to locate         aircraft photographs from this period in which the ï¿½Nï¿½ is not         displayed, though this practice appears to be the exception rather than         the rule. The requirement to use ï¿½Nï¿½ on aircraft operated within         U.S. boundaries did not come about until 1948.  
       In 1929, the Air Commerce Act was amended to modify the identification number convention.  Under the new plan, a combination of three numbers and an alpha         suffix of: E, H, K, M, N, V, W, or Y was approved.  This new block of identification numbers were consumed by the end         of 1934!  Class prefixes         were expanded to include ï¿½Rï¿½ for restricted and ï¿½Xï¿½ for         experimental aircraft.  A class prefix of ï¿½Gï¿½ for gliders was implemented as         well.  This class prefix was         canceled in 1937 when sailplanes and gliders were placed in the same         class as powered aircraft.  The         ï¿½Sï¿½ class for government-owned aircraft was also dropped in 1937.
       By         September 1, 1929, the DoC recognized the need to refine their         procedures. They acknowledged, in a document issued that date, that "some confusion exists amongst owners as to the privilege of using         the international symbol "N" on aircraft, licenses will be         issued to cover international operation, except in accordance with Air         Commerce Regulations, effective September 1, 1929, planes licensed for         experimental purposes shall not display the letter "N".         Hereafter, licenses (other than experimental) will not be issued as         C-100, or R-100, but as NC-100 or NR-100, etc. Owners of planes, except         experimental, may paint the international symbol "N" on the         wings and tail for operation in the United States, but will not be         required to do so. The symbol, however, must be applied before the plane         is operated either temporarily or regularly in a foreign country." This rule was later amended and the prefix "NC-" became         standard. It is important to note that the "dash" character         was regarded as a part of the registration. The Civil Aeronautics         Authority (CAA) continued to adhere to this policy as late as July 1934.
       On August 14, 1933, the CAA took a         policy stance with regard to numbers issued to aircraft. Up until the         post-World War II surplus boom, they were remarkably religious about         issuing one and only one number for each aircraft built. In the August         1933 document they went so far as to state "the Department has         consistently refused to assign new numbers to aircraft when there has         been sufficient identification, of even salvaged aircraft, to connect it         with some aircraft of which we have a record, and to which a number has         been previously assigned." Had they adhered to this rule, life         would have been much simpler for generations of aviation historians and         researchers that followed!
       In 1935, visionaries stepped in with claims that increasing registration         numbers from four to five numerals, increasing the block from 10000 to         99999, would provide a more than adequate number of identification         numbers.  Unfortunately,         even these were beginning to show signs of being gobbled up by the         beginning of World War II.  The         responsibility of administering aircraft identification registrations         passed to the Civil Aeronautics Administration portion of the CAA that         was formed in 1938.  The CAA         expanded the registration structure in 1946 to include three and four         numerals with other letter suffixes - the letters ï¿½Iï¿½ and ï¿½Oï¿½         were excluded to eliminate possible confusion with the numbers 1 and 0.  The block of numbers from 46000 to 79999 was generally reserved         for war-surplus aircraft. The class prefix of ï¿½Lï¿½ for limited type         certification was also created but lasted only until 1948.
       By December 9, 1938, the last of         the formerly Identified aircraft (primarily older aircraft for         which no ATC has been issued, homebuilt, and aircraft not intended to be         operated outside the confines of the state in which they were domiciled)         had been attrited. However, when an classified aircraft did not pass         inspection, the CAA came up with a new convention for covering these.         They would order the removal of the "C" from the "NC-" prefix, and thus the aircraft would become N-11471. This         has led many researchers on a merry chase. These were not licenses at         this point; they were Identification Marks.
       The class prefixes of ï¿½Cï¿½,         ï¿½Rï¿½, ï¿½Xï¿½ and ï¿½Lï¿½ were eliminated by amendment to the Civil         Aeronautics Regulations (CARs) on June 14, 1948, with only the ï¿½Nï¿½         being used.  By 1953 the         need to expand the available number of registration slots caused a rule         change to include double alpha suffixes with up to three numerals.  The letters ï¿½Rï¿½, ï¿½Xï¿½ and ï¿½Lï¿½ were replaced in 1948         with the requirement of a Restricted, Experimental, or Limited sign be prominently displayed at the cockpit entrance. This applied to         all new registration issued after December 31, 1948. Recertification of         aircraft in the "NL" category, which was defined as military         aircraft modified for limited civil use, was extended after an August         31, 1948 deadline - mainly to accommodate air racer owners at the         Cleveland Air Races. The CARs extended the deadline to remove the "C", "R", "X", or "L" characters         to January 1, 1951. 
Now         the Fun Begins
       What really makes all of         this challenging is that none of these rules appear to be cast in stone         and examples of exceptions abound.  For example, it is possible today to find examples of many of         these particular rules.  At         air shows one can see Golden Age era aircraft with NC registrations, and         war birds sporting NL and NX registration identifiers.  
       Even the Federal Government does         not follow their own specifications.  The Federal Government initially reserved identification numbers         1 through 26 for their aircraft.  This         was later expanded to 1 through 300. The original N1 designation was         assigned to a Department of Commerce de Havilland DH-4.  This aircraft wore the N1 registration even though to conform to         its owner's rules it should have carried the identification of NS1.  
       Because of the Department of         Commerce's practice of reassigning numbers after the sale, export or         destruction of an aircraft, the N1 number also shows up later on a         government Northrop Alpha 2, a Ford 5-AT, a Lockheed 12-A, a Douglas         DC-3 and is currently on a Gulfstream G-IV.  Furthermore, you can find private aircraft sporting registration         numbers in this designated range (N2 and N3 are registered to Cessna         Commercial Aviation Finance Corporation, but possibly leased to the         government).
       Since World War II, special request         registrations became popular leading to a proliferation of low-number         plus suffix registrations.  For         a fee, one could have just about anything as long as it was available.  The CAA provided regional offices with batch allocations for         distribution to add to the confusion.  
       All of these practices have         combined to make using the aircraft registration number a crude         reference tool.  An ï¿½Nï¿½         number alone is often insufficient to determine the particulars of an         aircraft.  Though many         aircraft have retained their original registration number through the         years, a large number of these registrations have also been reallocated         or simply changed with change of ownership.  
The First National Registrations
Civil registrations using the Underwriters         Laboratories all-letter system, 1921 to 1923:
N-AABA - Colonial Air             Transport 
N-ABCA - John M             Larsen, New York 
(Avro 504K)
N-ABCB - LMC Drilling             Company, Wichita
 (Laird Swallow)
N-ABCC - Akers             Airphoto Corporation, Chicago
 (Avro 504K)
N-ABCD - Ninimo Black             Airport Corporation,
 Chicago (Laird Swallow)
N-ABCE - John A             Hambleton, Baltimore 
(Avro 504K)
 Corporation, New York (Loening             Air Yacht)
N-ABCG - Diggins             Aviation Company, Chicago
 (Curtiss JN-4)
N-ABCH - Diggins             Aviation Company, Chicago
 (Curtiss JN-4)
N-ABCI - Aero Club of             Minneapolis 
(Curtiss JN-4C)
N-ABCJ - John C             Metzger, Chicago 
(Curtiss JN-4)
N-ABCK - David L             Behncke, Forest Park IL
 (Curtiss JN-4)
N-ABCL - David L             Behncke, Forest Park IL
 (Curtiss JN-4)
N-ABCM - E Hamilton             Lee, Chicago 
(Curtiss JN-4D)
N-ABCN - A W             Stephenson, Miles City MT
 (Curtiss JN-4D)
N-ABCP - Brooks, Banks & Smith Corp,
 Framingham, MA (Avro 504K)
N-ABCQ - C E Lessong,             Chicago 
(Standard J-1)
N-ABCR - R S Thompson,             Oakland CA
 (Standard J-1)
N-ABCT - H P Ayres,             Pittsburgh PA
 (Curtiss MF)
N-ABCU - Vincent             Astor, New York 
(Loening Air Yacht)
N-ABCV - Harold S             Vanderbilt, New York
 (Loening Air Yacht)
N-ABCX - Mrs K LaParle,             Chicago 
(Curtiss MF)
N-ABCW - George E Weaver, Chicago 
(Waco 4)
N-ABDA - B D Burley,             Chicago 
(Curtiss JN-4)
N-ABEA - L B Coombs,             New York 
(LWF G-3)
N-ABGA - J Sorenson,             Thomson IL 
(Curtiss JN-4D)
N-ABHA - T J Junker,             El Dorado KS 
(Laird Swallow)
N-ABIA - G Mosny Jr,             Indiana Harbor IN
 (Aeromarine 39-B)
N-ABJA - R R Ferguson,             Chicago 
(Lincoln Standard)
N-ABKA - Anna M             Parker, Hazelcrest IL
 (Curtiss JN-4D)
N-ABOA - Great Lakes             Aviation Co, Cleveland
 (Lincoln Standard)
N-ABQA - W F Bridgeman,             Ottumwa IA
 (Lincoln Standard)
N-AFOR - Stout             Airplane Co, Detroit 
(Stout Air Pullman)
N-BMUL - R W             Schroeder, Chicago 
(Standard J-1)
N-CAED - Spanish River             Pulp & Paper Co,
 Ontario, Canada (Dayton-Wright             FP-2)
N-MAAB - William Eaton             Jr, Boston 
(Travel Air C-6)
N-XAAA - Walter             Becker, Newark NJ 
(de Havilland DH-6)
The third Boeing         100 was acquired by Paul Mantz from the Boeing School of Aeronautics at         Oakland, California, in 1936 for air show and movie work. Registered NR873H,         the aircraft flew for many years for Mantz and was sold to Kermit Weeks         after Mantzï¿½s death. The aircraft was crushed in 1992 when Hurricane         Andrew blew a hangar roof down on it but is currently being restored to         flying condition, in Nevada. This photo of NR873H was taken at         Burbank Airport in July 1937. (Emil Strasser collection courtesy of         Gerry Liang)
This         article was compiled from information provided by AAHS member Mike         O'Rourke and several other American Aviation Historical Society members, AAHS Journal Vol. 2, No.4, documentation found on www.Aerofiles.com (created and maintained by former member K.O. Eckland), William T.       Larkins' Air Pictorial article from 1954, a wealth of detailed         information from Dan Hagedorn and the current FAA aircraft         registration database.  The         author particularly wishes to recognize AAHS member Matthew Rodina Jr.         of St. Croix, U.S. Virgin Islands for pointing us in the direction of         the most likely reason for the U.S. having ï¿½Nï¿½ as it national         aircraft registration mark.