World War 2 In Review: Grumman G-21 Goose: American Amphibious Flying Boat

This JRF-5 Grumman JRF-5 Goose was assigned to Naval Air Station Jacksonville, Florida (USA), in 1941 and remained on the station throughout the Second World War (photo taken in 1942). Only one of these aircraft flew from the station and was used for utility purposes, including photography. (Naval Air Station Jacksonville photo CNIC 042527)

The Grumman G-21 Goose is an amphibious flying boat designed by Grumman to serve as an eight-seat "commuter" aircraft for businessmen in the Long Island area. The Goose was Grumman's first monoplane to fly, its first twin-engined aircraft, and its first aircraft to enter commercial airline service. During World War II, the Goose became an effective transport for the US military (including the United States Coast Guard), as well as serving with many other air forces. During hostilities, the Goose took on an increasing number of combat and training roles.

Design and Development

In 1936, a group of wealthy residents of Long Island, including E. Roland Harriman, approached Grumman and commissioned an aircraft that they could use to fly to New York City. In response, the Grumman Model G-21 was designed as a light amphibious transport. Grumman produced a high-wing monoplane of almost all-metal construction—the trailing half of the main wing and all of the flight control surfaces except for the flaps were fabric-covered. It was powered by two 450 horsepower (340 kW) Pratt & Whitney R-985 Wasp Junior nine-cylinder, air-cooled, radial engines mounted on the leading edges of the wings. The deep fuselage served also as a hull and was equipped with hand-cranked retractable landing gear. First flight of the prototype took place on May 29, 1937.

Modifications

A number of modifications were made for the Goose, but the most numerous are those by McKinnon Enterprises of Sandy, Oregon, which holds 21 supplemental type certificates (STCs) for modifying G-21-series aircraft and which also manufactured four different conversions that were re-certified under a separate FAA type certificate as brand-new "McKinnon" airplanes. The first was the McKinnon model G-21C which involved replacing the original R-985 radial engines with four Lycoming GSO-480-B2D6 piston engines. It was approved under TC 4A24 on November 7, 1958, and two examples were converted in 1958–1959.

New Production

In November 2007, Antilles Seaplanes of Gibsonville, North Carolina, announced it was restarting production of the turbine-powered McKinnon G-21G Turbo Goose variant, now identified as the Antilles G-21G Super Goose. Pratt & Whitney Canada PT6A-34 turboprops flat-rated to 680 shp (510 kW) would have replaced the original PT6A-27 engines, and the airframe systems and especially the avionics (aviation electronics – i.e. radios and navigation systems) would have been updated with state-of-the-art "glass panel" instrumentation and cockpit displays. However, as of 2009, Antilles Seaplanes' manufacturing center has been foreclosed and sold at auction. The fate of new Goose production is currently unknown.

Type: Transport amphibious aircraft

Manufacturer: Grumman

Primary users:

United States Navy

United States Army Air Forces

Royal Air Force

Royal Canadian Air Force

Number built: 345

First flight: 29 May 1937

Variants: Kaman K-16B

Operational History

Envisioned as corporate or private flying yachts for Manhattan millionaires, initial production models normally carried two to three passengers and had a bar and small toilet installed. In addition to being marketed to small air carriers, the G-21 was also promoted as a military transport. In 1938, the U.S. Army Air Corps purchased the type as the OA-9 (later, in the war years, examples impressed from civilian ownership were designated the OA-13A). The most numerous of the military versions were the United States Navy variants, designated the JRF.

The amphibious aircraft was also adopted by the Coast Guard and, during World War II, served with the Royal Canadian Air Force in the transport, reconnaissance, rescue, and training roles. The G-21 was used for air-sea rescue duties by the Fleet Air Arm, who assigned the name Goose. A single aircraft was used briefly by No. 1 Air Ambulance Unit, Royal Australian Air Force in the Mediterranean.

After the war, the Goose found continued commercial use in locations from Alaska to Catalina and the Caribbean.

A total of 345 were built, with about 30 known to still be airworthy today (although around 60 are still on various civil registries, many of them are known to have crashed or been otherwise destroyed), most being in private ownership, some of them operating in modified forms.

Variants

G-21: The original production version, these were powered by two 450 hp (340 kW) Pratt & Whitney Wasp Junior SB engines, at 7,500 lb (3,400 kg) gross weight, with six passengers, and 12 were built, all converted to G-21A standards.

G-21A: Increased gross weight (8,000 lb (3,600 kg)), 30 built.

G-21B: Export coastal patrol flying boat armed with .30 in (7.62 mm) machine gun in bow and dorsal hatches and two 100 lb (45 kg) bombs underwing, 12 built for Portuguese Naval Aviation.

G-21C: Conversion by McKinnon Enterprises, these were re-engined with four 340 hp (250 kW) Lycoming GSO-480-B2D6 air-cooled, geared, and supercharged flat-six engines and fitted with retractable wingtip floats, a fiberglass radar nose, a one-piece wraparound windshield, and enlarged cabin windows; gross weight increased to 12,499 lb (5,669 kg) as result of internal structural reinforcements. Two were converted as piston-powered models G-21C in 1958–1959, and two other airframes subsequently were converted in 1968, but with two 550 shp (410 kW) Pratt & Whitney Canada PT6A-20 turboprops per STC SA1320WE as G-21C Hybrids. Two G-21C Hybrids were identical to the later 10,500 lb (4,800 kg) model G-21E, but they were never certified as such.

G-21D: One G-21C was further converted by McKinnon with an extended nose marked by two extra windows on each side and accommodating another four passengers. Recertified as G-21D in 1960. In 1966, it was re-engined with two 550 shp (410 kW) PT6A-20 turboprops and fitted with revised Alvarez-Calderon electric flaps in accordance with STC SA1320WE, retaining the G-21D designation, but subsequently identified as the McKinnon "Turboprop Goose".

G-21E: A fully certified new model, it was based on a simplified turbine conversion of the McKinnon G-21C, with 550 shp (410 kW) PT6A-20 engines (680 shp (510 kW) Pratt & Whitney Canada PT6A-27 engines optional) and more fuel, but without all of the structural reinforcements of the G-21C. 10,500 lb (4,800 kg) gross weight. One converted.

G-21G: The final McKinnon conversion also was fully certified as a new model with 680 shp (510 kW) PT6A-27 engines, 586 US gal (2,220 L; 488 imp gal) of fuel, and 12,500 lb (5,700 kg) gross weight. Two converted.

Kaman K-16B: Experimental tilt wing aircraft, with JRF-5 fuselage powered by two General Electric YT58-GE-2A engines; one built but not flown.

XJ3F-1: Prototype eight-seat utility amphibian, built for the US Navy; one built in 1938.

JRF-1: Production XJ3F-1, five built for US Navy.

JRF-1A: Similar to JRF-1, but with target towing gear and camera hatch added, five built for US Navy.

JRF-2: U.S. Coast Guard version with provisions for carrying stretchers; seven built.

JRF-3: Similar to the JRF-2, fitted with autopilot and deicing boots on the wing leading edges for Arctic operations. Three built for US Coast Guard.

JRF-4: Similar to JRF-1A, these could carry two underwing depth bombs. Ten built for US Navy.

JRF-5: Major production version with bomb racks, target towing and camera gear, and deicing gear; 184 built. In 1953, a modified JRF-5 tested hydro skis for the US Navy.

JRF-5G: 24 JRF-5s transferred to the US Coast Guard.

JRF-6B: Navigation trainer purchased for supply under Lend-Lease; 50 built.

OA-9: Transport and air-sea rescue for United States Army Air Forces, 26 ordered in 1938, supplemented by five JRF-6Bs under the same designation.

OA-13A: Three G-21As impressed by the USAAF.

OA-13B: Two JRF-5s transferred to the USAAF.

Goose Mk.I: British designation for three JRF-5s supplied to the Fleet Air Arm.

Goose Mk.IA: British designation for 44 JRF-6Bs, supplied under Lend Lease for observer training by the 749 Naval Air Squadron in Trinidad.

Goose Mk.II: British designation for two JRF-5s staff transports for British Air Commission in the United States and Canada.

Operators

Military Operators

Argentina

Argentine Naval Aviation

Six aircraft were used 1947–1966.

Australia

Royal Australian Air Force

A single aircraft was used briefly by No. 1 Air Ambulance Unit RAAF in the Mediterranean.

Bolivia

Bolivian Air Force

At least two aircraft (one JRF-2 and one JRF-6B) received in 1942.

Brazil

10 used for anti-submarine patrols during Second World War.

Canada

Royal Canadian Air Force

36 received

Cuba

France

Honduras

Honduran Air Force

Indonesia

Indonesian Air Force

Japan

Japan Maritime Self-Defense Force

Paraguay

Paraguayan Naval Aviation

Peru

Peruvian Air Force

Portugal

Portuguese Naval Aviation

Portuguese Air Force

Sweden

Swedish Air Force

United Kingdom

Royal Air Force (several impressed examples by 24 Squadron and ATA)

Royal Navy (44 Lend Lease examples)

United States

United States Army Air Corps

United States Army Air Forces

United States Navy

United States Coast Guard

Aircraft on Display

Canada

B-77 – G-21A in storage at the Canada Aviation and Space Museum in Ottawa, Ontario.

Indonesia

PB-521 – G-21A on static display at Suryadarma Air Force Base in Subang Regency, West Java.

Sweden

37810 – JRF-5 under restoration for static display at the Swedish Air Force Museum in Linköping, Östergötland.

United States

1048 – G-21A on static display at the Steven F. Udvar-Hazy Center of the National Air and Space Museum in Chantilly, Virginia.

1086 – G-21A on static display at the National Naval Aviation Museum in Pensacola, Florida.

1157 – G-21A under restoration for static display at the Tongass Historical Society in Ketchikan, Alaska.

B-102 – G-21A on display at the Alaska Aviation Museum in Anchorage, Alaska.

B-122 – G-21A on static display at the Evergreen Aviation & Space Museum in McMinnville, Oregon.

B-130 – G-21A on static display at the Historic Aircraft Restoration Project in Brooklyn, New York.

Reproduction – G-21A on static display at the Cradle of Aviation Museum in Garden City, New York.

Specifications (JRF-5 Goose)

Crew: 1-3

Capacity: 5-7

Length: 38 ft 6 in (11.73 m)

Wingspan: 49 ft 0 in (14.94 m)

Height: 16 ft 2 in (4.93 m)

Wing area: 375 sq ft (34.8 m2)

Airfoil: root: NACA 23015; tip: NACA 23009

Empty weight: 5,425 lb (2,461 kg)

Gross weight: 8,000 lb (3,629 kg)

Powerplant: 2 × Pratt & Whitney R-985-AN-6 Wasp Junior 9-cylinder air-cooled radial piston engines, 450 hp (340 kW) each

Propellers: 3-bladed variable-pitch propellers

Maximum speed: 201 mph (323 km/h, 175 kn) at 5,000 ft (1,500 m)

Cruise speed: 191 mph (307 km/h, 166 kn) at 5,000 ft (1,500 m)

Range: 640 mi (1,030 km, 560 nmi)

Service ceiling: 21,300 ft (6,500 m)

Rate of climb: 1,100 ft/min (5.6 m/s)

Wing loading: 21.3 lb/sq ft (104 kg/m2)

Power/mass: 0.11 hp/lb (0.18 kW/kg)

Bombs:

2 × 325 lb (147 kg) depth charges

2 × 250 lb (110 kg) GP bombs

Bibliography

Ablitzer, Fabrice. "Round-Out". Air Enthusiast, No. 79, January/February 1999. p. 79.

Donald, David, ed. American Warplanes of World War II. London: Aerospace Publishing, 1995.

Francillon, René J. and Gary L. Killion. "Sauce for the Goose – turbine style". Air International, July 1993, Vol. 45, No 1, pp. 53–57. Stamford, UK: Key Publishing.

Francillon, René J (March 2008). "Grumman G-21 "Goose": L'oie qui ne se pose jamais". Le Fana de l'Aviation (in French). No. 460. pp. 32–40.

Green, William. War Planes of the Second World War: Volume Five Flying Boats. London: Macdonald, 1968.

Hagedorn, Daniel P. (1993). Central American and Caribbean Air Forces. Tonbridge, Kent, UK: Air-Britain (Historians) Ltd.

Ledet, Michel (April 2002). "Des avions alliés aux couleurs japonais" [Allied Aircraft in Japanese Colors]. Avions: Toute l'Aéronautique et son histoire (in French) (109): 17–21.

March, Daniel J., ed. British Warplanes of World War II. London: Aerospace Publishing, 1998.

Niccoli, Riccardo. "Pottuguese Numerology: Serial systems used by the Aeronautica Militar and the Força Aerea Portuguesa". Air Enthusiast, May–June 1998, No. 75. pp. 33–40.

Núñez Padin, Jorge Felix (2009). Núñez Padin, Jorge Felix (ed.). JRF Goose, PBY Catalina, PBM Mariner & HU-16 Albatros. Serie Aeronaval (in Spanish). Vol. 25. Bahía Blanca, Argentina: Fuerzas Aeronavales.

Swanborough, Gordon and Peter M. Bowers. United States Navy Aircraft since 1911. London: Putnam, Second edition, 1976.

Thruelsen, Richard. The Grumman Story. New York: Praeger Publishers, Inc., 1976.

Winchester, Jim, ed. "Grumman Goose/Mallard." Biplanes, Triplanes and Seaplanes (The Aviation Factfile). Rochester, Kent, UK: Grange Books plc, 2004.

Preserved ex-British JRF-6B Goose in U.S. Navy JRF-1 markings. (Ted Rufus Ross, 17 October 2006)

Royal Canadian Air Force Goose. (Air Ministry)

Grumman JRF-5 on 5 February 1945. (NASA Langley)

Grumman Goose s/n 798 of RCAF. This aircraft is in fact the former Texaco-owned Goose, NC20648, bought by the Canadians during 1942. (City of Vancouver Archives CVA 1184-1561)

Grumman JRF-5 Goose. (Bureau of Aeronautics, Navy Department)

Goose Mark I, MV993, of No. 24 Squadron RAF based at Hendon, Middlesex, in flight. This aircraft was formerly G-AFKJ, owned by Lord Beaverbrook. (Imperial War Museum CH 6901)

Grumman JRF-5G Goose from air station Port Angeles in flight over the Olympic Mountains in Washington, 2 February 1943. (National Archives 80-G-K-5178)

Aircraft at the U.S. Naval Air Station Guantanamo Bay, Cuba, circa 1944. Visible are (l-r): a Vought OS2U Kingfisher, a Howard NH-1, a Grumman JRF-5 Goose, and four Martin PBM-3 Mariners. (US National Archives and Records Administration, cataloged under the National Archives Identifier (NAID) 179036550)

Airmen and women with Grumman OA-9 Goose, USAAC, Isla Grande, Puerto Rico, 1 January 1939. (DeGolyer Library, Southern Methodist University)

A Grumman JRF Goose amphibian is hoisted on board the U.S. Navy escort carrier USS Long Island (ACV-1) from a seaplane wrecking derrick (YSD), off Palmyra Island, 19 April 1943. (U.S. Navy photo 80-G-66769 via U.S. Naval History & Heritage Command)

A U.S. Navy Naval Aircraft Factory N3N-3 Yellow Peril (BuNo 2885) photographed in front of building 57, Naval Air Station Anacostia, Washington D.C. (USA), in 1940. A Grumman JRF-4 Goose (BuNo 3852), assigned to NAS Anacostia, is in the background. This aircraft was sold by the U.S. Navy on 31 July 1946. It later crashed on 3 December 1946 at the Llanganattes Range, Ecuador (civil registration HC-SBL). (U.S. Navy photo 80-G-K-13392 via U.S. Naval History & Heritage Command)

Junior Birdsmen in front of Grumman OA-9 Goose, USAAC, Isla Grande, Puerto Rico, 1 January 1939. The Junior Birdmen of America was a national organization created by the Hearst newspaper publishers to promote airmindedness among young people. (DeGolyer Library, Southern Methodist University)

Grumman OA-9 Goose, USAAC. (Bill Larkins)

Grumman OA-9 Goose, USAAC, Isla Grande, Puerto Rico, 1 January 1939. (DeGolyer Library, Southern Methodist University)

Grumman JRF Goose.

Grumman JRF-2 s/n V176, U.S. Coast Guard.

Grumman JRF-3 s/n V192, U.S. Coast Guard, riding at anchor off White Fish Point, Michigan.

Grumman JRF-2 s/n V176, U.S. Coast Guard, on tarmac.

Grumman JRF-2 s/n V176, U.S. Coast Guard.

Grumman Goose MV993, after being impressed from Lord Beaverbrook’s ownership.

The cockpit of a pre-war G-21A, and a period executive interior.

Grumman JRF-2 Goose s/n V176 was part of the initial batch supplied to the U.S. Coast Guard.

The unique dorsal hatch fitted only to the G-21B flying boats of the Aviação Naval Portuguesa.

Fleet Air Arm Grumman Goose Mk.Ia s/n FP486 in Tobago, 1942.

Grumman Goose Mk.I s/n MV993 of No. 24 Squadron RAF based at Hendon, Middlesex, in flight. This aircraft was formerly G-AFKJ, owned by Lord Beaverbrook. (Imperial War Museum CH 6901)

Grumman Goose Mk.I s/n MV993 of No. 24 Squadron RAF. (Imperial War Museum CH 6899)

Grumman JRF-6B flying boat operated by the British Fleet Air Arm as the Goose Mk.IA in flight in April 1942.

Grumman JRF dropping practice bomb during training mission. Note the white lower surface carried up to the underside of the horizontal stabilizer. (NASM, Rudy Arnold collection)

The potential utility of the design was not lost on the U.S. Coast Guard, who soon placed orders for the Goose outfitted for the Search and Rescue (SAR) role. Pictured at Floyd Bennet Field in 1940 are two JRF and a Hall PH flying boat in the Yellow Wings scheme.

The U.S. Army Air Corps designated the aircraft the OA-9 and ordered 26 examples in 1938. These were used as light transports in addition to SAR duties. Another attractive scheme.

The British Fleet Air Arm also adopted the type, and the Goose was also operated by Canada. Here is FB486 in the Temperate Sea Scheme on a delivery flight in 1942.

After America’s entry into the war, the USCG used the Goose for anti-submarine patrol. At least two kills were claimed, but post-war analysis reduced this to one damaged. Here Coast Guard personnel load depth charges. Modelers should note the color and condition of the ordnance. (NASM, Rudy Arnold collection)

The Goose was well-suited for rescue work. Here is a posed shot demonstrating casualty evacuation. (NASM, Rudy Arnold collection)

The red surround to the national insignia dates this photograph to the Summer of 1943. An interesting detail is the retractable wheel, which was apparently painted without the benefit of masking the tire; modelers take note! (NASM, Rudy Arnold collection)

Grumman Goose s/n 941 was flown by No. 13 Operational Training Squadron based at RCAF Station Sea Island, British Columbia. Prior to military service the aircraft was on the Canadian civil aircraft registry as CF-BQE. It also at one time carried the code AN*J. This aircraft was sold through war assets to North West Air Services in Seattle, Washington on 5 January 1945.


Another view of Grumman Goose s/n 941 at the same time as the previous photo.

Grumman Goose s/n 942, presumably after No. 13 Operational Training Squadron's code letters AN had been superseded by MK in May 1942 and before the latter were removed in October 1942.

Grumman Goose s/n 798 of no. 122 (K) Squadron RCAF in late 1942/early 1943. This is a zoom from a much larger picture showing it anchored at Prince Rupert along with No. 7 (BR)'s Sharks.

Grumman Goose s/n 798 again. A nice clear picture with some good detail, but not certain when it was taken. Certainly, it appears to have a nice fresh paint scheme. The same comment applies to the photos of s/n 941 posted above.

Grumman Goose s/n 924, taken while on the strength of No. 111 (CAC) in 1940, show that for part of that period operated with both civilian and RCAF markings.

Grumman Goose s/n 796 during its service in EAC, probably 1942. This photo (actually a motion picture frame) may serve to indicate the extremely large number of color schemes the RCAF used on the type during the war.

Grumman OA-9 Goose, USAAC, in Hawaii, pre-war.

Grumman JRF s/n V176 of the U.S. Coast Guard.

Two Grumman JRF Gooses at the factory, circa Summer 1943.

Grumman G-12A Goose "W2H" of the Royal Naval Observer Training School at Piarco, off Trinidad in 1944. A number of these sturdy little amphibians served with this unit.

Grumman JRF-2 Goose s/n V174 of the U.S. Coast Guard.

Grumman JRF Goose s/n V191 of the U.S. Coast Guard.

Interior view of Grumman JRF-2 Goose of the U.S. Coast Guard.

Pilot's side of cockpit of Grumman JRF Goose of the U.S. Coast Guard in 1940.

Control panel of a Grumman JRF Goose of the U.S. Coast Guard in 1940.

Grumman Goose Mk. II s/n 925, RCAF Station Borden, Ontario, 14 Aug 1940. (RCAF photo)

Grumman Goose Mk. II s/n 917, RCAF, 29 October 1939. (Library and Archives Canada photo MIKAN No. 3581487)

NX925 before delivery. NX925 was the U. S. civil aircraft registration it had when purchased by the Canadian government. (RCAF photo)

Grumman Goose Mk.II s/n 925), RCAF Station Borden, Ontario, circa August 1940. (RCAF photo)

Grumman Goose Mk.II s/n 983. This aircraft is mounted on wheeled dollies. (Library and Archives Canada photo MIKAN No. 3583400)

Grumman Goose s/n 924 with General Andrew McNaughton, 31 October 1939. (Library and Archives Canada photo MIKAN No. 3581543)

Grumman Goose Mk.II s/n 386, 25 July 1945. This RCAF image RE2822-8 was taken 25 July 1945, showing Grumman Goose (Serial No. 383), U.S. Navy (BuNo. 37797), taken on charge by No. 12 (Communication) Squadron on 8 March 1944. The RCAF roundel marking was first painted [LAC Skip Rutledge] on Canadian flown Wellington Mk. X aircraft in Tunisia, North Africa, in August 1943. This same “unofficial” Maple Leaf marking was now adopted by No. 12 (Communication) Squadron and painted on all V.I.P. aircraft flown at RCAF Station Rockcliffe, Ontario. It is interesting to note [for model builders] the original [over painted] U.S. Navy “National U.S. Star” is still showing behind the new RCAF nose markings. Two of these aircraft were photographed still wearing the U.S. Star on 29 August 1944, so the RCAF markings and nose art were applied soon after that date. (Library and Archives Canada photo MIKAN No. 3583792)

Grumman Goose Mk.II s/n 388), Boundary Bay, No. 5 Operational Training Unit (OTU), RCAF, Spring 1944.

Grumman Goose Mk.II, RCAF, August 1941. (Library and Archives Canada photo MIKAN No. 3589806)

Grumman Goose Mk.II, RCAF, August 1941. (Library and Archives Canada photo MIKAN No. 3589811)

Grumman Goose Mk.II, January 1944. (Library and Archives Canada photo MIKAN No. 3650857)

Grumman Goose Mk.II s/n 917, RCAF, 1939. (Library and Archives Canada photo MIKAN No. 3545907)

Grumman Goose Mk.II s/n 917, 24 October 1939. (Library and Archives Canada photo MIKAN No. 3581488)

Grumman Goose s/n 942 (MK-H), presumably after No. 13 Operational Training Squadron's code letters AN had been superseded by MK in May 1942 and before the latter were removed in October 1942. On the ramp at Pat Bay Air Station, Victoria, BC.

Grumman OA-9, Shemya, Alaska.

Grumman Goose (AN-G) presumably before No. 13 Operational Training Squadron's code letters AN had been superseded by MK in May 1942 and before the latter were removed in October 1942. Starting a patrol at Pat Bay Air Station, BC, circa 1944 .

Grumman Goose Mk.III (G-21A) s/n 917, RCAF, crashed near Cape Yakataga, Alaska, 21 July 1942. One died on impact, one drowned attempting rescue, five rescued after 11 days in the wilderness.