AFV Club 1/350 Guppy II

KIT #: -
REVIEWER: Tom Cleaver
NOTES: Conversion. Kit modified with scratchbuilt “northern sail”


The GUPPY Submarine:

            The major technological advance in diesel-electric submarines was the development of the snorkel, which allowed the operation of the diesel engines at periscope depth, and the development of the Type XXI U-boat by the Germans, the first submarine designed for greater performance underwater than on the surface. The snorkel was widely adopted by the navies of the world and improved after the war, while the Type XXI submarine revolutionized submarine design in all navies.

            The US Navy designed the “Tang” class to take advantage of everything learned from the Type XXI U-boat, the new boats were so much better they made the existing fleet boat obsolete, but these were too expensive in the post-war period to produce enough of them to satisfy all the needs for submarines.   In 1949, the Navy began the Greater Underwater Propulsive Power Program, for which the acronym GUPPY was created by dropping the lat “P” to convert and backfit existing late-production “Gato” and “Balao” class fleet submarines with many of the German Type XXI submarine design features. Deck guns and anti-aircraft armament were removed, the outer hull was streamlined, the conning tower replaced by a streamlined sail, larger propellers were fitted, more air conditioning was installed for the greater heat generated by the electric motors, and the battery capacity doubled. The end result was submarines which were capable of 18.2 knots submerged, equaling the Type XXI, and exceeding their surfaced speed by 0.4 knots.

            The GUPPY program included three major phases. Guppy I, which was essentially experimental, involved only two boats, Odax (SS‑484) and Pomodon (SS‑486), which both became part of the main program, and led to the GUPPY IA AND IB boats; GUPPY II, which converted 24 boats during the late 1940s and early 1950s by reducing the diesels from four to three to increase battery size and power; and GUPPY III, which updated several GUPPY II submarines by lengthening the hull for additional equipment. The key features of all three were extensive streamlining of the hull and sail, larger and more powerful batteries, and a snorkel air‑breathing system.

             The GUPPY IA, IB, II and III submarines were distinguished by a tall sail, termed the “northern sail.”  

These boats were "rode hard."  In the Atlantic, they had to support ASW training with US and NATO Task Groups, run barrier patrols in the Greenland-Iceland-UK-Gap, that narrow passage through which the Soviet submarines would deploy to threaten the Atlantic sea lanes.)  In the Pacific, boats from Pearl Harbor, San Diego and Yokosuka watched the exit points from the North Pacific ports such as Vladivostok.  The US and other NATO boats watch the Kola Peninsula. These deployments often  found the boats in extremely rough weather; on the North Atlantic run, they operated in Force 5 and 6 and higher seas constantly, while those in the Pacific often had to deal with typhoons and enormous storms out of the Gulf of Alaska. The streamlined GUPPY bow dug deep into the waves and the dearly “step sail” gave little protection to the bridge crew, while control during snorkeling was difficult at  best and sometimes impossible.  The tall “northern sail” solved the problems, and all GUPPY boats were so modified during their careers.   

            Most information about the operations of GUPPY submarines during the Cold War remains classified to this day.  Without converting the fleet boats of World War II to the GUPPYs of the Cold War era, the success of submarine cold war operations  would not have been possible.   These submarines "held the Line" until the SSNs and SSBNs took over.


            The Balao class USS Blackfin (SS‑322) was launched March 12, 1944 at Electric Boat Co. in Groton, Connecticut and commissioned July 1944.  She arrived at Pearl Harbor on September 11, 1944, and undertook five war patrols in the South China Sea and Yellow Sea.  She sank the Japanese destroyer Shigure and a cargo ship on January 24, 1945, her only victories during the war.

            In November 1950 Blackfin began conversion to a GUPPY submarine, being recommissioned on May 15, 1951. She spent her career until retirement with Submarine Force, Pacific Fleet, based at San Diego.

            During her career, Blackfin was used in two movies: “Move Over, Darling” in 1963 starring Doris Day, James Garner, and Polly Bergen, and “Ice Station Zebra” in 1968, starring Rock Hudson, Ernest Borgnine, and Patrick McGoohan, during which filming she operated on battery power surfaced to simulate a nuclear boat.  Your reviewer had the opportunity to go to sea aboard Blackfin during the 1964 SEATO exercises for two days of submarine familiarization, as the guest of an old high school friend who was a crew member (which is why this model is Blackfin and not some other boat).

            Blackfin operated in the Gulf of Tonkin on several patrols during the Vietnam War, all of which are classified, but supposedly include two missions to put Navy SEALS ashore in North Vietnam, as well as acting as a “lifeguard” for Yankee Station aviation operations.  She was decommissioned and struck from the Naval Vessel Register on September 15, 1972 and was sunk by torpedo as a target in "SubSinkEx Project Thurber" off San Diego on May 13, 1973.

            In 1966, having just left Subic Bay enroute to Yankee Station while conducting operations with USS Bainbridge, Blackfin dove close aboard Bainbridge to show her crew a dive.  As a result of winds from one direction and current from another, the two ships had a minor collision, with Blackfin being swept underneath Bainbridge, causing her to take about a 55‑60 degree roll to starboard, severely damaging the raised periscopes and radio antennae; this resulted in Blackfin returning to Subic for two weeks to receive and install replacements.


             As mentioned in my previous review of the AFV Club kit, AFV Club made the mistake of providing the GUPPY upper hull in their 1943 Gato class fleet submarine kit that I purchased.  I was left with a submarine hull and no conning tower after using the AFV Club parts on the Yankee Modelworks Gato hull.


             After perusing photos, I scratchbuilt a “northern sail” using Evergreen sheet styrene to build an internal structure and outer cover.  This was the only “hard part” of the project, and I am not entirely certain the dimensions of this sail are entirely correct, having “eyeballed” the whole thing, but it looks “close enough.”



            Some GUPPY boats - including Blackfin in at least one point of her career - appeared in the haze-grey/black camouflage similar to World War II fleet boats, but the majority operated in flat black with lower hulls in red anti-fouling paint.  While they carried hull numbers on the sail and bow while in port or on non-operational cruises, when they went to war they painted out the numbers.

             The kit was painted with Tamiya “Flat Black,” highlighted with “NATO Black”, and Tamiya “Hull Red.”


             Not a difficult conversion.  Another example that you can indeed turn lemons into lemonade.  I do look forward to the release of the AFV Club early GUPPY submarine.

Tom Cleaver

May 2011

 Review Kit courtesy of HobbyLink Japan.

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