Grumman JF Duck

 

The Grumman JF Duck was an American single-engine amphibious biplane manufactured by Grumman during the 1930s decade.

The Duck was designed in 1932, inspired by the designs of previous amphibious aircraft like the Loening OL and was one of the first designs of the, back then, newly created Grumman. 

The prototype, XJF-1, flew for the first time on 24th April 1933, in Farmingdale, Long Island with Paul Hovgard at the controls.

The XJF-1 was a compact single-bay biplane with a crew of two, seated in tandem under an enclosed canopy. It was powered by a single Pratt & Whitney R-1830-62 radial engine and was armed with a single .30 in caliber flexible machine gun placed at the rear, operated by the observer. It could also carry a single 100 lb (45 kg) bomb under each lower wing. In the rear of the float, two passengers could be accommodated side-by-side. This compartment was accessed through a set of folding doors located in the floor of the rear cockpit. The float was faired into the fuselage, like previous Loening models did. The main landind gear retracted into the float, while the non-retractable tailwheel, mounted at the rear of the main float, acted as a water rudder too. It was also equipped with an arresting hook, which was mounted at the rear of the fuselage. 

The XJF-1 was delivered to the US Navy and underwent evaluation at NAS Anacostia, in Washington DC on 4th May 1933. As a result, the vertical tail surfaces were changed because the original triangular ones resulted in some longitudinal instability. The surfaces were redesigned to the broader squarer vertical surfaces found in the production models of the regular JF Duck. The XJF-1's tail was redesigned, redelivered and accepted into service. Unfortunately, the XJF-1 crashed in the James River on 8th March 1934 when operating with VX-1D5, a naval test and development unit, based at NAS Norfolk in Virginia.

The Duck was ordered into production in 1934. The production version differed from the prototype in having a different rudder, fin and its armament deleted (although it still had provision for a defensive machine gun) with a third crew member (a radio operator) was added. The US Navy issued a contract for twenty-seven JF-1 and the first JF-1 entered into service at NAS Norfolk, Virginia in May 1934. The US Marine Corps (USMC) also undertook the type during February 1935. In the US Navy the JF-1 served in VJ-1 (Utility Squadron 1), attached to USS Wright (AV-1) with detachments aboard the main carriers of the time, USS Saratoga (CV-3), USS Lexington (CV-2) and USS Ranger (CV-4) and also aboard USS Heron (AM-10) in the Asiatic Fleet.

It was also assigned at the Navy's main shore bases like Coco Solo in the Panama Canal Zone, Pearl Harbor in Hawaii and the Navy Yard, at Cavite in the Philippines. 

The JF-2 was a development of the JF-1 built in 1934-1935 for the US Coast Guard. The JF-2 were powered by a single Wright R-1820-102 rated at 700 hp. The JF-2 were equipped with a radio direction finder loop antenna placed on the fuselage spine behind the canopy and it lacked arrestor gear. The JF-2 served with the US Coast Guard from land bases in New Jersey, Washington, Florida, North and South Carolina, Mississippi, and California, as well as aboard USCG cutter Taney (WHEC-37), in Honolulu, Hawaii, the USCG icebreaker Spencer (WPG-36) in Cordova, Alaska, where it also served in the Bering Sea Patrol unit. Four JF-2 were transferred to the US Navy. 

The JF-3 was a further development built both for the US Navy and USMC reserve units in 1935. Only five of them were built and were powered by a single 750 hp Wright R-1820-80 engine. Like the JF-2 it also lacked the arrestor hook. A single JF-3 was delivered to each of the major reserve bases at NRAB Brooklyn, in New York, NRAB Seattle in Washington, NRAB Long Beach, California and NRAB Opa-Locka, in Florida. 

The JF Duck also had one foreign customer: Argentina. In 1937 Argentine Government bought eight Grumman model G-20 Ducks directly from Grumman. The G-20 was similar to the JF-2 used by the US Coast Guard. The first Argentine G-20 flew for the first time in December 1936 and by February 1937 they were all delivered. They replaced the outdated Vought O2U-1As in the Escuadrón de Observación Naval (Naval Observation Squadron). They operated from BAN (Base Aérea Naval - Naval Air Base) Comandante Espora, other Argentine Navy's bases like BAN Puerto Belgrano and aboard the cruisers ARA Almirante Brown (C-1) and ARA Veinticinco de Mayo (C-2). They served until 1948. 

Sources:

1. https://en.wikipedia.org/wiki/Grumman_JF_Duck

2. Squadron Signal - Aircraft in Action Mini 7 - Grumman JF Duck

3. https://www.valka.cz/topic/view/160020/Grumman-JF-1-Duck

4. http://wings-aviation.ch/51-Profiles/G/G-Basis-en.htm

5. http://elmuan.blogspot.com/2011/08/1937-grumman-g-15-y-g-20-duck.html (translated)

6. http://www.histarmar.com.ar/Armada%20Argentina/AviacionNaval/REC-AT-GrummanDuck.htm (translated)