The Grumman JRF Goose was originally developed as a civil transport aircraft, but saw service in the US Navy, Coast Guard and in Britain and Canada as a utility transport, coastal patrol aircraft and navigation trainer.
The original aircraft was produced in 1937, as the Grumman G-21 Goose. It was a flying boat with a high wing, two step hull, retractable undercarriage and fixed floats under the wing tips. It had a crew of two and could carry six or seven passengers. It entered production as the G-21A, with more powerful engines.
In 1938 the US Navy ordered a single example of a modified version of the aircraft, the Grumman G-26, with the Naval designation XJ3F-1, putting it in the same sequence as the J2F Duck and J4F Widgeon. However all production aircraft were placed into the utility transport category, so became the JRF.
The Navy then placed an order for twenty aircraft, which were all originally to be delivered as the JRF-1. This was a seven seat transport aircraft. Only ten were delivered as the JRF-1, and the other ten were completed as the JRF-4 (Grumman G-39), which could carry light bombs. After the US entry into the war two civilian G-21 Geese were impressed into the Navy and were designated as JRF-1s.
Five of the original JRF-1s were later converted into target tugs and photographic aircraft, becoming the JRF-1A.
The US Coast Guard ordered ten Geese in 1939-40. Of these seven were delivered as the JRF-2 (Grumman G-39), presumably with the same bomb racks as the JRF-4.
The last three Coast Guard aircraft were completed as the JRF-3, which had anti-icing equipment and an autopilot and was for use in Arctic waters.
The last ten aircraft from the original order for twenty JRF-1s were instead completed as the JRF-4 (Grumman G-39). These were similar to the -1, but could carry two 250lb bombs or depth charges under the wings, allowing them to be used on anti-submarine warfare patrols. Two more JRF-4s were produced from Geese impressed into the Navy after the US entry into the war.
The JRF-5 (Grumman G-38) was the main production version, with a total of 184 (including sub-variants) built. Production began in 1941. The JRF-5 had newer engines and could carry cameras for survey work.
Twenty-four of the JRF-5s went to the Coast Guard, as the HRF-5G.
The JRF-6B was produced for lend lease. It was similar to the JRF-5 but was equipped to operate as a navigation trainer. Fifty were produced, of which 44 went to Britain as the Goose IA, one to Bolivia and five to the USAAF, where they became the OA-9.
This designation was given to 16 JRF-5s that went to Canada and 4 that went to Britain.
This designation was given to 44 JRF-6Bs that were delivered to Britain under Lend Lease. Msot were used at Piarco in the British West Indies.
Engine: Two Pratt & Whitney R-985-AN-6s
Power: 450hp each
Crew: 2 or 3, with 4 to 7 passengers
Length: 38ft 6in
Height: 16ft 2in
Empty weight: 5,425lb
Gross weight: 8,000lb
Maximum take-off weight:
Max speed: 201mph at 5,000ft
Climb Rate: 1,100ft/ min
Service ceiling: 21,300ft
Range 640 miles
Bomb load: Two 250lb bombs or depth charge under wings