REPUBLIC P-47 THUNDERBOLT P47
The P-47 was one of America's leading fighter airplanes of WW II. It made its initial flight on May 6, 1941, but the first production article was not delivered to the AAF until March 18, 1942, more than three months after the attack on Pearl Harbor. On April 8, 1943, the P-47 flew its first combat mission, taking off from England for a sweep over western Europe. During the next several months, AAF pilots learned that the Thunderbolt could out-dive any Luftwaffe airplane encountered. An auxilary fuel tank was suspended under the fuselage beginning in 1943, permitting the P-47 to escort AAF heavy bombers much farther into German territory.
In addition to establishing an impressive record as a high-altitude escort fighter, the P-47 gained recognition as a low-level fighter-bomber because of its ability to absorb battle damage and keep flying. By the end of the war, the Thunderbolt had been used in every active war theater with the exception of Alaska. In addition to serving with the AAF, some were flown in action by the British, Free French, Russians, Mexicans, and Brazilians.
The P47 D on display, one of more than 15,600 built, was donated by Republic Aviation Corporation in Nov. 1964.
P47 SPECIFICATIONS
Span: 40 ft. 9 in.
Length: 36 ft. 1 in.
Height: 14 ft. 2 in.
Weight: 13,500 lbs. loaded
Armament: Eight .50-cal. machine guns & ten 5
in. rockets or 1,500 lbs. of bombs.
Engine: Pratt and Whitney R-2800 of 2,300 hp.
Serial number: 42-23278
P47 PERFORMANCE
Maximum speed: 433 mph
Cruising speed: 260 mph
Range: 1,100 miles (with auxiliary fuel tank)
Service Ceiling: 40,000 ft.
P47 Variants
P-47C
Essentially similar to the P-47 B, the initial P-47 Cs
featured strengthened all-metal control surfaces, an
upgraded GE turbosupercharger regulator and a short
vertical radio mast. After the initial manufacture of a
block of 57 P47 Cs, production moved to the P-47C-1,
which had an eight inch (200 mm) fuselage extension
forward of the cockpit at the firewall to correct center
of gravity problems, ease engine maintenance and allow
installation of a new engine mount. There were a number
of other changes, such as revised exhausts for the oil
coolers, and fixes to brakes, undercarriage and
electrical system as well as a redesigned rudder and
elevator balance. The 55 P47 C-1s were followed by 128
P-47 C-2s which introduced a centerline hardpoint with
under-fuselage shackles for either a 500 pound (227 kg)
bomb or a 200 U.S. gallon (758 L, 166.5 imp. gal) fuel
tank that conformed to the underside of the fuselage. The
main production P47 C sub-variant was the P-47 C-5 which
introduced a new whip antenna and the R-2800-59 engine
with water-methanol injection with a war emergency power
rating of 2,300 horsepower (1,716 kW). With the use of
pressurized drop tanks, the P-47 C was able to extend its
range on missions beginning 30 July 1943.[6]
P-47 D / P47 G / X P47 K /
X P-47 L
Republic P-47 D Thunderbolt, nicknamed "Jug;"
during World War II, the P-47 served in every active
combat theater and with many Allied air forces.
Republic P-47 D Thunderbolt, nicknamed "Jug;"
during World War II, the P-47 served in every active
combat theater and with many Allied air forces.
Refinements of the Thunderbolt continued, leading to the
definitive P47 D, of which 12,602 examples were built.
The "D" model actually consisted of a series of
evolving production blocks, the last of which were
visibly different from the first.
The first P-47Ds were actually the same as P-47Cs.
Republic could not produce Thunderbolts fast enough at
its Farmingdale plant on Long Island, so a new plant was
built at Evansville, Indiana. The Evansville plant built
a total of 110 P-47Ds, which were completely identical to
P-47C-2s. Farmingdale aircraft were identified by the
"-RE" suffix after the block number, while
Evansville aircraft were given the "-RA"
suffix.
The P-47D-1 through P-47D-6, the P-47D-10, and the
P-47D-11 successively incorporated changes such as the
addition of more engine cooling flaps around the back of
the cowl to reduce the engine overheating problems that
had been seen in the field. Engines and engine subsystems
saw refinement, as did the fuel, oil and hydraulic
systems. Additional armor protection was also added for
the pilot.
The P-47 D15 was produced in response to requests by
combat units for increased range. The internal fuel
capacity was increased to 375 U.S. gallons (1,421 L) and
the bomb racks under the wings were made "wet"
(equipped with fuel plumbing) to allow a jettisonable
drop tank pressurized by vented exhaust air to be carried
under each wing, in addition to the belly tank. Five
different auxiliary tanks were fitted to the Thunderbolt
during its career:
* 200 U.S. gallon (758 L) ferry tank, a conformal
tub-shaped jettisonable tank made of paper, which barely
cleared the ground on grass airfields, was used as an
interim measure between 30 July and 31 August 1943;
* 75 U.S. gallon (284 L) drop tank, a teardrop-shaped
steel tank produced for the P-39, was adapted to the P-47
beginning 31 August 1943, initially carried on a belly
shackle but used in pairs in 1944 as underwing tanks;
* 108-gallon (409 L) drop tank, a cylindrical paper tank
of British design and manufacture, used as a belly tank
beginning in September 1943 and a wing tank in April
1944;
* 150 U.S. gallon (568 L) drop tank, a steel tank first
used as a belly 20 February 1944, and an underwing tank
22 May 1944;
* 215 U.S. gallon (810 L) belly tank, a wide, flat steel
tank developed by VIII Service Command that allowed
performance-degrading wing pylons to be removed, was
first used in February 1945.
The tanks made of plastic-impregnated (laminated) paper
could not store fuel for an extended period of time, but
they worked quite well for the time it took to fly a
single mission. These tanks were cheaper, lighter in
weight, and were useless to the enemy if recovered after
being dropped — not only did they break apart, but
they did not provide the enemy with any reusable
materials that could be scavenged for their own war
effort. With the increased fuel capacity, the P-47 was
now able to perform escort missions deep into enemy
territory. A drawback to their use was that fighters
could not land with the tanks in place because of the
hazard of rupture and explosion. Fighters recalled from a
mission or that did not jettison for some reason were
required to drop paper tanks into a designated
"dump" area at their respective fields,
resulting in substantial losses of aviation fuel.
The P-47 D-16, D-20, D-22 and D-23 were similar to the
P47 D-15 with minor improvements in fuel system, engine
subsystems, a jettisonable canopy, and bulletproof
windshield. Beginning with the block 22 aircraft, the
original narrow-chorded Curtiss propeller was replaced by
propellers with larger blades, the Evansville plant
switching to a new Curtiss propeller with a diameter of
13 feet (3.96 m) and the Long Island plant using a
Hamilton Standard propeller with a diameter of 13 feet 2
inches (4.01 m). With the bigger propellers having barely
six inches of ground clearance, Thunderbolt pilots had to
learn to be careful on takeoffs to keep the tail down
until they obtained adequate ground clearance, and on
landings to flare the aircraft properly. Failure to do so
damaged both the propeller and the runway.
Even with two Republic plants rolling out the P-47, the
USAAF still was not getting as many Thunderbolts as they
wanted, consequently, an arrangement was made with
Curtiss to build the aircraft under license in a plant in
Buffalo, New York. Most of the Curtiss Thunderbolts were
intended for use in advanced flight training. The Curtiss
aircraft were all designated P-47G, and a "-CU"
suffix was used to distinguish them from other
production. The first P-47G was completely identical to
the P-47C, the P-47G-1 was identical to the P47 C-1,
while the following P-47 G-5, P-47 G-10, and P-47 G-15
sub-variants were comparable to the P-47 D-1, P47 D-5 and
P47 D-10 respectively. Two P47 G-15s were built with the
cockpit extended forward to just before the leading edge
of the wing to provide twin tandem seating, designated T
P-47 G. The second crew position was accommodated by
substituting a much smaller main fuel tank. The
"Doublebolt" did not go into production but
similar modifications were made in the field to older
P-47s, which were then used as squadron "hacks"
(miscellaneous utility aircraft). Curtiss built a total
of 354 P-47 Gs.
Bubbletop P-47
All the P-47s to this point had a "razorback"
canopy configuration with a tall fuselage spine behind
the pilot which resulted in poor visibility to the rear.
The British also had this problem with their fighter
aircraft, and had devised the bulged "Malcolm
hood" canopy for the Spitfire as an initial
solution. This was fitted in the field to many North
American P-51 Mustangs, and to a handful of P-47Ds (and
far more on P-47Bs and P-47Cs). However, the British then
came up with a much better solution, devising an
all-round vision "bubble" canopy for the Hawker
Typhoon. USAAF officials liked the bubble canopy, and
quickly adapted it to American fighters, including the
P51 and the Thunderbolt. The first P-47 with a bubble
canopy was a modified P47 D-5 completed in the summer of
1943 and redesignated XP-47K. Another older P-47 D was
modified to provide an internal fuel capacity of 370 U.S.
gallons (1,402 L) and given the designation XP-47L. The
bubble canopy and increased fuel capacity were then
rolled into production together, resulting in the block
25 P47 D (rather than a new variant designation). First
deliveries to combat groups began in May 1944.
It was followed by similar bubble-top variants, including
the P47 D-26, D-27, D-28 and D-30. Improvements added in
this series included engine refinements, more internal
fuel capacity, and the addition of dive recovery flaps.
Cutting down the rear fuselage to accommodate the bubble
canopy produced yaw instability, and the P-47D-40
introduced a dorsal fin extension in the form of a narrow
triangle running from the vertical tailplane to the radio
aerial. The fin fillet was retrofitted in the field to
earlier P47 D bubble-top variants. The P-47D-40 also
featured provisions for ten "zero length" stub
launchers for 5 inch (127 mm) High Velocity Aerial
Rockets (HVARs), as well as the new K-14 computing
gunsight. This was a license-built copy of the British
Ferranti GGS Mark IID computing gyroscopic sight which
allowed the pilot to dial in target wingspan and range,
and would then move the gunsight reticle to compensate
for the required deflection.
The bubbletop P47s were nicknamed "Superbolts"
by combat pilots in the field.[8]
P-47 N
The P47 N was the last Thunderbolt variant to be
produced. It was designed as an escort fighter for the
B-29 Superfortress bombers flying raids on the Japanese
home islands. Increased internal fuel capacity and drop
tanks had done much to extend the Thunderbolt's range
during its evolution, and the only other way to expand
the fuel capacity was to put fuel tanks into the wings.
Thus, a new wing was designed with two 50 U.S. gallon
(190 L) fuel tanks. The second Y P-47 M with this wing
flew in September 1944. The redesign proved successful in
extending range to about 2,000 miles (3,200 km), and the
squared-off wingtips improved the roll rate. The P47 N
entered mass production with the uprated R-2800-77(C)
engine, with a total of 1,816 built. The very last
Thunderbolt to be built, a P-47 N-25, rolled off the
production line in October 1945. Thousands more had been
on order, but production was halted with the end of the
war in August. At the end of production, cost of a
Thunderbolt was $83,000 in 1945 U.S. dollars.
(credits: US Air Force History Support Office)