Grumman
J2F Duck
In 1932 Grumman submitted their design
for the amphibious G-7 to the U.S. Navy to meet the Navy's specifications for a
plane in the "Utility" category.
The Navy accepted the plane in 1934 as the JF-1, and ordered 27 of the
aircraft.
The "Duck" became one of the Navy's all-around workhorses, and was used before and during WWII as a transport, reconnaissance plane, bomber, and rescue plane. Although often referred to as a floatplane, the central float is integral with the fuselage, making the plane a flying boat in truth. The plane seats two crew members in the dorsal cockpit, the pilot and an observer/radio operator/rear gunner (depending upon the plane's role). In the central fuselage, just above the main float, there is space for two passengers or a stretcher. A set of landing gear and an arrestor hook rounded out the plane, making it capable of operating from carriers, airstrips, or the water.
The Duck burns 34.6 gallons of fuel per
hour. A full load of fuel costs $43.
Grumman
J2F Duck
Subassemblies:
Light Fighter-Bomber chassis +3; Medium Fighter wings with Biplane option +2; 3
retractable wheels +1; one Small AFV Waterproofed pontoon [Body:U] +2; two
Small Weapon Waterproofed pontoons [Wings:U] +0.
Powertrain: 691-kW Aerial supercharged HP gasoline
engine with 691-kW prop; one 150-gallon main fuel tank [Body] and one 65-gallon
auxiliary fuel tank [Body]; 4,000-kW battery.
Occ.: 2 CS Body, 2 PS Body
Cargo: 0 Body
Armor F RL B T U
Body: 2/3 2/3
2/3 2/3 2/3
Wings: 1/2C 1/2C 1/2C 1/2C 1/2C
Wheels: 2/3 2/3 2/3 2/3 2/3
Pontoons: 2/3 2/3 2/3 2/3 2/3
Weaponry:
Aircraft
LMG/.30-cal Browning LMG [Body:B] (1,000 rounds).
Equipment:
Body: Navigation instruments, arrestor hook,
medium range radio transmitter and receiver with direction finder, casemate
mount. Wings: two 325-lb. hardpoints.
Statistics:
Size: 34'x39'x14' Payload: 0.92
tons Lwt.: 3.85 tons
Volume: 312 Maint.: 38
hours Cost: $27,123
HT: 9.
HPs: 165 Body, 160 each Wing, 15
each Wheel, 150 central Pontoon, 45 each wing Pontoon.
aSpeed:
190
aAccel: 5 aDecel:
15 aMR: 4
aSR: 1
Stall
Speed: 59 mph. Take Off Run: 316
yards. Catapult Launch: 280 yards. Landing Run: 348 yards.
gSpeed: 214
gAccel: 11 gDecel:
10 gMR: 0.5
gSR: 2
Ground
Pressure: Very High. 1/8 Off-Road
Speed.
wSpeed: 36
wAccel: 5 wDecel:
2 (4.5) wMR: 0.1
wSR: 4
Draft:
1.5 feet. Flotation Rating: 15,702 lbs.
Design
Notes:
Historical wing area was 409 sf. Design loaded weight was 9,327 lbs. This is 17% above the historical, but the
design includes equipment for all of the Duck's historical roles. Likely, the plane would only be equipped for
a specific mission parameter. Removing
all ordnance for a transport/rescue role, for example, reduces weight to within
10% of the historical. MG load-outs are
a guess. Design aSpeed was 198 mph
fully loaded. Historical loaded weight
and wing area for all performance calculations. Historical stall speed was 70 mph, but his made the design unable
to lift off from water, so the design stall speed was used for landing and
take-off performance calculations.
Variants:
The JF-1 (or G-7) (1933) was the initial
production model. It featured 100-lb.
wing hardpoints and a 522-kW engine. 27
built.
The JF-2 (or G-9) (1934) was similar to
the JF-1, but mounted a radio direction finder. The antenna interfered with the field of fire from the MG, and so
was removed whenever the Browning was installed. There was no arrestor hook.
14 built.
The JF-3 (or G-10) placed the antenna in
the cockpit, resolving the MG issue.
There was no arrestor hook. 5
built.
The J2F-1 (1936) featured a 560-kW
engine. The arrestor hook was
reinstalled, and the bombload increased.
20 built.
The J2F-2 was equipped with a 589-kW
engine, and a forward facing Browning MG.
21 built. The USMC's -2A had
twin MGs for the gunner and an extra pair of bomb racks. 9 built.
The J2F-3 (1939) was J2F-2s fitted with
luxury accommodations for transporting naval officers. 20 built.
The J2F-4 (1939) featured minor
modifications to the J2F-2. 32 built.
The J2F-5 (1941) installed a 708-kW
engine and an increased bomb load. 124
built.
The J2F-6 (1942) was the -5 built by
Columbia Aircraft Corporation. (Grumman
had begun working on more significant aircraft following the attack on Pearl
Harbor.) The powerplant was upgraded to
783-kW. 330 built for the Navy and
Coast Guard.
The AO-12, -12A, and -12B were a
modification of nine -5 and -6 Ducks between 1942 and 1948 for air/sea rescue
used by the USAF.
The G-15 and G-20 were -5 and -6 Ducks
produced and exported to Columbia, Argentina, and Mexico.
From the Aerodrome for GURPS
© 2008 by Jim Antonicic