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Alphabet Soup -- US Military Aircraft Designations Explained
                                                                           by Job Conger
        I recently corresponded with a friend about PBY-2s used to fight forest fires today. When I saw reference to that type, I wrote him a note saying "I hate to be a nit picky aviation historian, but you should know that if there are ANY PBY-2s (or) PBY-4s) flying anywhere today, I will eat my hat. He was kind enough to send me the links where he found the references to those types along with a good natured, "Start chomping." I wrote him back and explained the point which concluded "...My hat's intact. So how's YOUR appetite?
       The confusion suffered by so many dedicated aviation historians is all Robert MacNamara's fault. You may recall, he's the "genius" who guided brave men to their premature rendezvous with "deathtiny" in a little country called Vietnam. Maybe you've heard of it. It was in all the papers. When he was President John F. Kennedy's Defense Department Director (or position to that effect) he also tried to force the Navy version of the General Dynamics F-111 down their throats (in a manner of speaking -- not literally) and approved a re-writing of the US military aircraft designation system that still has well intentioned but uninformed historians shaking their heads and other aviation enthusiasts walking blindly into attributing designations to aircraft which never carried them. From the early 30s to 1962, the designation system worked just fine. MacNamara is the one to thank for this snafu maximus.
     The logic behind the designation system that worked so well is wonderfully simple. Take the designation F4D-1, the designation given to the fourth Douglas fighter design accepted by the US Navy for a prototype or production contract.
    A few words about names. The F4D-1 also given the OFFICIAL NAME Skyray. For more about names visit The Kname Game
     The US Navy called their fighters "fighters" more than 15 years while the US Army Air Corps and subsequent evolutions of the service called their fighter "pursuits." Anyone reading the designation F4D-1 in 1954 would have understood that the airplane was a fighter (F), that it was the fourth fighter design accepted for development by the USN, the D was the letter-designator assigned to Douglas, and that the -1 was the first version made. The "Ford" (unofficial name) never went beyond a mass-built first version. Other navy fighters did. Consider the F4U-7 Corsair, the seventh major variant of the fourth fighter given a designation by the USN for a design from Vought.
      The designation PBY-5A was used from the day the first amphibious US Navy Catalina came off the assembly line at Consolidated's San Diego plant until they were retired from service. Consolidated was a real pioneer in the manufacture of durable, dependable flying boat patrol aircraft. Their first was the PY-1 (P for patrol, Y the designator for Consolidated, -1 first version  built only as a prototype. In 1935 the design which became the first PBY-1 was built. Following the -1 came the dash 2  (PBY-2), dash 3 (-3) and 4.  The PB stood for patrol bomber. The first PBY-5 (fifth version of this design) significanly improved the -4, though early -5s were built as flying boats. When the amphibious landing gear was introduced to what was otherwise an essentially unchanged airplane, those with landing gear were designated PBY-5A. Though both versions were called the Catalina, the designation made clear the distinction between the flying boat -5 and the amphibious -5A.
     The 5 and 5A were built at the same time through most of the war. After the war, only the -5, 5A and some -6s remained in service, and most service personnel called them PBYs. From a practical standpoint, the unknowing-and-glad-to-be-that-way aviation enthusiast can call a PBY-5A a Plaskro Tarpoquail and that's okay. When good people professing to be serious students of aviation history, it's important to THIS aviation historian (that would be me, Job Conger) that we use the designation that coincides with the airplane at hand.
      Today there's confusion over the airplanes being used to fight forest fires in the Western states. People are calling the four-engine land-based plane which replaced US Navy versions of USAAF Liberators in land-based maritime patrol "PBYs." I don't understand why. Those aircraft are ex-USN Consolidated PB4Y-2s.
      Again, let's consider what the designation means. PB -- the familiar patrol bomber designator  4 -- the fourth patrol bomber design given a PB designator by the USN.  Y -- the manufacturer designator for Consolidated. Let's IMAGINE a PB4F-1. We'd understand immediately that this imaginary plane was the fourth patrol bomber built by GRUMMAN to be given a designator. It didn't happen, but that would have been the designation of it had happened.
     A final check back with our F4D-1. In 1970, most military types would remember the Skyray as the F4D-1 even though McDonnell -- thanks to MacNamara's 1962 re-designation debacle -- was building the F-4D Phantom for the US Air Force. Hyphens are important. I don't care what comic book you find it in, there "ain't no such thang" as an airplane designnated    F  4  -  D (additional spacing mine). The F4-D is not a Skyray. The F4-D is not a Phantom or even a Phantom II. There is also no F-6F Hellcat. That incredible airplane was designated F6F, and variants ran from the F6F-1 through F6F-6. Production variants of the F6F were limited to the F6F-3 and -5.
       To make matters even more confusing (THANK YOU Mr. MacNamara! MAY I HAVE ANOTHER?) the 1962 frenzy re-designated the F4D Skyray as F-6. I urge readers to grab a copy of United States Military Aircraft since 1911 byGordon Swanborough and Peter M. Bowers and published by Putnam, also by Funk & Wagnals. The book has been out of print, but if you can find one, the appendix in the back makes heads AND tails out of the confusion. It's an excellent read!
   Look for more about military designations of England, Germany and Japan here in the months ahead.
   If this ramble inspires questions from YOU about designations or darn near anything else about historical aviation. please e me.  

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Last modified: November 22, 2002