An RO-5E is an RO-5E is an RO-5E…

Grumman G-73T Mallard serial no. J-27, N2969, Which crashed in Miami in Dec. 2005

But what’s in an aircraft name – or official model designation?

Aircraft model designations and formal identifications actually mean more than most people seem to realize. Gertrude Stein wrote “a rose is a rose is a rose.” William Shakespeare similarly wrote “a rose by any other name would smell as sweet.” The Federal Aviation Administration, on the other hand, not being known for its poetry or its prose, wrote that the official identification of each aircraft is based primarily on the following parameters: Builder’s name. Model designation. Builder’s serial number. Type certificate number, if any. Production certificate number, if any.

There are actually a few more factors explained under Title 14 of the United States Code of Federal Regulations (14 CFR) Part 45, Section 45.13(a) but they either pertain just to engines in particular or serve more simply as a generic “catch-all” statement along the lines of “any other information the FAA finds appropriate.”

Too often people do not understand or follow these relatively simple guidelines – and the FAA itself compounds the problem by not following them either, or by muddying the waters with policies and practices that do not adhere to the strict letter of the actual regulations. Note that 14 CFR 45.13(a) does NOT say anything about “designer” or “Type Certificate Holder” (i.e. owner) in terms of identifying the “make” or manufacturer of an aircraft. The only term that regulation used was “builder” so on that basis it matters not one bit who originally designed the aircraft in question. It also matters not one bit who may have built similar aircraft previously – and it matters still not one little bit who owns the TC under which it was certified (if applicable.) It really is supposed to matter only who actually “built” the particular aircraft in question.

In practice, even the FAA violates this regulation by allowing owners to register or otherwise “formally” identify their aircraft based not on what it actually is (by whom it was actually built and as what) but rather by what it only represents or seems to be. The FAA even typically but strictly speaking incorrectly writes the applicability sections of Airworthiness Directives based on “TC Holder” identifications instead of the more proper and correct “builder” identification. While it is proper to file an AD note under the current TC Holder, changes in ownership of the TC in question do not change the formal identification of the aircraft they are meant to cover.

Airworthiness Directives

Grumman G-73T Mallard serial no. J-27, N2969, Which crashed in Miami in Dec. 2005

One such example is Airworthiness Directive 2006-01-51 which was first issued on an Emergency basis on December 30, 2005 in direct response to the tragic fatal crash of Chalk’s Ocean Airways Flight 101, Grumman G-73T Mallard serial no. J-27, registered as N2969, in Miami, FL less than 2 weeks earlier. That AD incorrectly identifies the aircraft to which it applies as “all Frakes Aviation (Gulfstream American) Model G-73 (Mallard) series airplanes” – but there are no such things. Neither Frakes nor Gulfstream American ever “built” a G-73 series Mallard aircraft.

Every G-73 Mallard ever built was in fact actually built by the Grumman Aircraft Engineering Corporation and as such they are all still properly and officially identified as “Grumman” G-73 Mallard aircraft. The fact of the matter is that first Gulfstream American of Savannah, GA and later Frakes Aviation of Cleburne, TX were simply subsequent owners or “Holders” of FAA Type Certificate no. A-783 under which the affected aircraft were originally built and certified.

It is also a fact that when Grumman sold TC A-783 first to Gulfstream American and then they in turn later sold it to Frakes, those sales had absolutely no effect on the officially identification of the actual aircraft in question; they all continued to be “Grumman” G-73 series aircraft in terms of registration and airworthiness certification.

French-built SCAN Type 30 serial no. 32, N78X, a license-built “copy” of a Grumman G-44A Widtgeon

License-built Aircraft

Similarly, even though they were in fact not “built” actually by Grumman, every French-built SCAN Type 30 (license-built “copies” of the Grumman model G-44A Widgeon) that is registered in the U.S. is identified incorrectly as a “Grumman” aircraft. Based on 14 CFR 45.13(a) they are in fact not “Grumman” aircraft at all; they are “SCAN” aircraft because they were “built” actually by the Societe’ de Construction Airo-Navales in Rochelle, France – not by Grumman on Long Island, NY. (Note: each sub-type of Widgeon can be identified easily on the basis of its serial number; all models G-44 were serial numbers 1201 through 1400 inclusive. All models G-44A were serial numbers 1401 through 1476 and all French-built SCAN Type 30 aircraft were serial numbers 1 through 41.)

An Eastern Aircraft (General Motors) FM-2 essentially a license-built copy of a Grumman F4F Wildcat.

The same pretty much holds true for World War II military surplus FM-2 Wildcat fighters and TBM Avenger torpedo bombers. They are examples of Grumman “designs” but the specific aircraft in question were not built by Grumman; that is the significance of their different model designations. If they had been built actually by Grumman, then they would have been designated as F4F and TBF series aircraft but they were really built by the Eastern Aircraft division of General Motors in Trenton, NJ instead, hence their FM-2 and TBM designations by the U.S. Navy.

An Eastern Aircraft (General Motors) TBM-3E – a license-built copy of a Grumman TBF.

Internally to Grumman, the Wildcat was design number G-36 and the Avenger G-40, but at Eastern Aircraft they were known as the models GM-1 and GM-2 respectively. While they are examples of essentially the same type designs (with only minor differences in some cases) in terms of who actually “built” them they were officially different aircraft – yet in spite of that and in spite of the fact that “Grumman” is not mentioned anywhere on their respective data tags, in the U.S. all civilian-owned FM-2 and TBM aircraft are currently registered and otherwise formally identified as “Grumman” aircraft – in apparent violation of 14 CFR 45.13(a).


On that basis too, there are “problems” as far as I am concerned with the registration of a lot of the war-surplus “Boeing” B-17 Flying Fortresses that are still flying under civilian ownership as so-called “warbirds.” The fact of the matter is that the production of a lot of B-17’s was contracted out to other manufacturers during the war. A model B-17G-xx-BO was built actually by Boeing in Seattle (wherein the “xx” is a particular production “block” number.) The “BO” manufacturer code distinguishes such aircraft from others with a “BN” code having been built by Boeing in Renton, WA or a “BW” code aircraft that was built in Wichita, KS.

A so-called “Boeing” B-17G-70-VE that was built actually by Lockheed-Vega

However, all B-17G Flying Fortress aircraft built by Douglas at its Long Beach, CA plant were officially designated as B-17G-xx-DL aircraft and those built by the Vega division of Lockheed were similarly designated as B-17G-xx-VE aircraft. Based on the strict “letter of the law”, i.e. 14 CFR 45.13(a) the remaining airworthy examples of those aircraft really should be registered and otherwise now “officially” identified as “Douglas” and “Lockheed” B-17G aircraft respectively because that is who actually “built” them. Even as hard as that is for dilettante warbird fans and even professional warbird experts to swallow.

That is not to say that in casual conversation or any other unofficial forum they can’t be discussed or treated as “Boeing” aircraft because they certainly are examples of an iconic Boeing design – but in terms of official identification and certification as civilian aircraft operated under the authority of Title 14 of the Code of Federal Regulations, the basis for their “proper” and legal identification is clear and simple, yet still not actually followed or obeyed even when so obviously applicable.

“Builder’s” Serial Numbers

In the same vein, 14 CFR 45.13(a) also specifies that all aircraft are supposed to be identified in terms of their “builder’s” serial number. Just to be clear once and for all, a military serial number on a warbird is NOT a “builder’s” serial number. A military serial number is just a customer’s inventory control number, essentially no different than the “fleet” numbers on a police car or a tradesman’s van. In spite of this fact and contrary to the regulation already referenced several times over – and in spite too of the clear guidance also given in FAA Advisory Circulars AC 21-12C and AC 21-13 pertaining to the identification of aircraft in regard to the issuance of certificates of airworthiness – every single Grumman HU-16Albatross” registered in the United States for another example is “incorrectly” identified using a “former” military serial number. In some cases, it is not even a correct or valid former military serial number. In not one single case is an Albatross properly identified using its well-known Grumman serial or construction number, all of which actually range from G-1 up to G-464.

Part of the confusion with Grumman Albatross aircraft in particular is the fact that they were such useful aircraft, they were frequently transferred between different branches of the U.S. military and even to foreign military services – and with each transfer, they were given a new model designation and serial number. In simplest terms, every short-wing variant of the Grumman Albatross was considered by Grumman to be a model or “design number” G-64. For the USAF, they were originally built as the model SA-16A and others eventually for the U.S. Navy as the model UF-1.

N116AG, a 1951 Grumman Albatross incongruously currently identified as a Navy model HU-16C with an improper version of a USAF serial no. 17164 (actually 51-7164) which is really Grumman serial no. G-214.

First One Thing – Then Another

In the case of the Albatross now registered as N116AG, it was actually built for the Air Force as a SA-16A and initially assigned AF serial no. 51-7164. Its actual Grumman serial number was G-214, but in practice, the Air Force typically painted its serial number on its tail as 17164 – dropping both the leading number 5 and the intermediate hyphen for the sake of simplicity. That same Albatross was later transferred to the U.S. Navy as a model UF-1, in fact specifically modified for Arctic operations as a model UF-1L, and assigned Navy Bu. no. 142429.

After 1962, the Navy UF-1 series was re-designated as HU-16C and the UF-1L became an LU-16C. Even so, while it is now registered with the FAA as a supposed “Navy” short-wing model HU-16C, it is also now mis-identified as Air Force serial no. 17164. To me, that is all the proof that is needed to show why supposedly “former” military serial numbers and maybe even military model designations should never be used to identify such aircraft in terms of civilian operation and certification. Regardless of what it was to various military services over the years, the Albatross now registered as N116AG was always a Grumman G-64 with “builder’s” serial no. G-214 and that never changed.

Metal vs. Paper

In one of the worst cases of bureaucratic incompetence that I have heard of to date, a friend who bought and restored a surplus Canadian military jet trainer, a Canadair CT-133 Silver Star, which is a license-built copy of a Lockheed T-33A Shooting Star, was forced by an (IMHO) “ignorant” bureaucrat at the FAA to alter the “builder’s serial number” on the actual engraved metal data tag in his aircraft in order to match the paperwork that he got from the Canadian military when the airplane was declared surplus and sold for civilian use.

A Lockheed T-33 Shooting Star – or is it?

The engraved metal data tag as originally installed, as on many other military aircraft, contained both the OEM serial number and an initial military serial, or as I put it before, inventory control number. However, during the military service life of the aircraft, the organization of the military service operating it changed. In 1968, the whole of the Canadian military was re-organized and the Royal Canadian Air Force was subsumed into the larger Canadian Armed Forces. At that time, the military serial number of the particular aircraft in question was replaced. While its Canadair (“builder’s”) serial number of 6xx remained the same, its RCAF serial number 216xx was changed to the new CAF serial number 1336xx – and it was so noted on all of its certification and maintenance documentation up through the time that it was sold for civilian ownership.

Instead of understanding what had happened and even better, realizing that it did not matter one itsy little bit because their own regulations specified the use of the “builder’s serial number” in any case, the FAA bureaucrat in question forced the new owner of the airplane to have a trophy engraving shop physically alter the original engraved metal data tag to reflect the CAF serial number identification. That is wrong! However, in dealing with an intransigent FAA bureaucrat, the owner had no choice but to go along. That he had to do so is also wrong!

All other things being equal, the assumption always should be that the engraved metal data tag is a higher order of identification than any paperwork and in the case of any conflict should take precedence. But apparently that lesson was lost on one more paper-pusher.

It All Means Something

When you actually know what is going on, the numbers and letters of official model designations and serial numbers actually mean something; they are not random. The aforementioned Grumman Wildcat, the F4F series, was designated as such because it was a Naval Fighter (F), 4th such design (4) built by Grumman (F) and the TBF Avenger was a Naval Torpedo Bomber (TB) first such design (in such cases the number 1 is suppressed) built by Grumman (F).

Canadian Vickers-built Canso A serial no. CV-417, originally delivered to the RCAF as serial no. 11084 but painted to represent RCAF serial no. 9754

Similarly, the iconic PBY series of “Catalina” flying boats were designed and built originally by Consolidated Aeronautics in San Diego, CA. (Note some people claim that the name “Catalina” is appropriate only in regard to such aircraft in RAF or Royal Navy service, but the fact of the matter is that the name originally bestowed by the British was eventually adopted officially by the U.S. Navy too.) However, because of their usefulness, not only did Consolidated expand its own production to a second factory in New Orleans, LA, they also licensed several other companies to build additional examples too. In Canada, a division of the Boeing Company built their own copies of the PBY-5 pure flying boat (with no wheels built-in.)  In U.S. Navy service they were designated as PB2B-1 and PB2B-2 aircraft (Navy Patrol Bomber 2nd type built by Boeing) but in RCAF service they were designated as “Canso” aircraft.

Canadian Vickers (later to become Canadair) also license-built copies of the PBY-5A (i.e. Consolidated model 28-5A) as their own models CL-1 which in turn in U.S. Navy service would have been designated as models PBV-1A (Navy Patrol Bomber 1st type built by Vickers – sub-type 1, amphibian) but all of which in fact went to the RCAF as “Canso A” aircraft or to the U.S. Army Air Corps as model OA-10A-xx-VI aircraft. The Canadian Vickers-built aircraft were easily distinguished by their CV- serial numbers (not to be confused with the original designers later corporate identities as Consolidated Vultee or Convair.)

The fact of the matter, as I obviously like to say, is that not all such aircraft were in fact “PBY’s” or even “Catalina’s” so it is not correct to paint them all with that same brush. But just as with the serial number on my friend’s Silver Star, because they don’t know any better, the bureaucrats at the FAA recently registered a certain Canadian Vickers-built ex-RCAF “Canso A” as a “Consolidated PBY-5A” in the U.S. in spite of the facts that it was not “built” by Consolidated, never served with the U.S. Navy as a PBY-5A, and has a tell-tale “CV-xxx” Canadian Vickers serial number – in apparently complete contradiction to their own regulations for the proper identification of aircraft. It really helps to know what you’re doing but it seems that you can get a job at the FAA even when you don’t.

At least in the case of the PBY sunk in Pearl Harbor on December 7th, 1941 about which we recently ran a separate story, it was in fact really a “PBY” for a change, but like they say “even a broken clock is right twice a day.”

Dave Marion is the Technical Content Editor at As A&P and IA with 29 years of experience in aircraft maintenance, he is also a Commercial Pilot with Airplane, Single & Multi-Engine, and Instrument ratings. He has a BA from Colgate University in 1984 and also graduated cum laude from Embry-Riddle Aeronautical University (DAB) with a BS in Aviation Technology in 1990. He can be reached along with all of the editors via E-Mail: [email protected]

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