We are searching data for your request:
Upon completion, a link will appear to access the found materials.
Subject Index: Republic P-47 Thunderbolt
Aircraft- Combat RecordThe Republic P-47 Thunderbolt was produced in greater numbers than any other American fighter aircraft. Despite its large size and unwieldy appearance, it was a more than capable fighter aircraft, accounting for close to 4,000 Axis aircraft in aerial combat.
The “Jug” P-47 Thunderbolt – Workhorse of WWII in 30+ Photos
Republic’s P-47 Thunderbolt was the backbone of the U.S. Air Force during Second World War and was certainly one of the most iconic American aircraft, alongside its successor, the P-51 Mustang.
Nicknamed as the “Jug” due to its silhouette looking like a milk jug, it was also the heaviest Allied fighter aircraft, achieving a weight of up to eight tons when fully loaded. Capable of carrying five-inch rockets or a bomb load of 2,500 pounds, together with its eight .50 cal machineguns serving as its primary armament, this medium-range fighter-bomber was usually involved in high-altitude escort missions and ground attacks on targets of opportunity.
A P-47 Thunderbolt during take off
Entering active service in November 1942, a contingent of Thunderbolts was dispatched to England as part of the 56th Fighter Group, under the command of the 8th Air Force. It first saw combat in March 1943, during a mission over occupied France, but due to a radio malfunction, the mission turned out to be a catastrophe.
Very soon, the P-47s stationed in England were refitted with new, English-made radio equipment, resuming active service.
P-47 Thunderbolts from the 318th Fighter Group taking off from East Field on Saipan, Marianas Islands in October 1944.
From that point on the Jug proved to be a formidable opponent. After encountering it in combat, Heinz Bäer, a Luftwaffe Ace, noted that the P-47 could absorb an astounding amount of lead and had to be handled very carefully.
This was, in fact, true ― its sturdy airframe, powered by the mighty Pratt & Whitney R-2800 Double Wasp engine, together with its armored cockpit provided safety for the pilot. The unique bubble-top canopy offered excellent visibility, despite its weight limiting the airplane’s maneuverability.
366th FG P-47 Machine Gun Maintenance at Saint Pierre du Mont Airfield A-1, 1944
Even though P-51 Mustangs subsequently replaced Thunderbolts in a number of squadrons, its initial users, the 56th, decided to stick with the Jug until the very end of the war.
Serving both in Europe and in the Pacific, the P-47 Thunderbolt flew over 746,000 sorties of all types, claiming some 3,752 air-to-air kills of enemy aircraft. It’s loss rate, however, was equally as high ― some 3,499 P-47s were downed during the course of the war.
Apart from US service, the P-47 Thunderbolt aircraft saw action as part of the British RAF, the French Air Force, Soviet Air Force and also as part of the contingent of pilots hailing from Brazil and Mexico who also participated as part of the Allied war effort.
F-47 Thunderbolts in 1947
After WWII, Thunderbolts were exported to various countries of Latin America and the Middle East while small numbers were provided to countries such as China and Yugoslavia.
One of the most recognizable U.S. ground-attack aircraft today, the Fairchild Republic A-10 Thunderbolt II adopted its name from its WWII-era predecessor.
Alexander de Seversky
Alexander Nikolaivitch Prokofiev de Seversky was born into a wealthy aristocratic family in Tiflis, Georgia, then part of the Russian Empire. Though thousands of miles away from any American city, this family name would help to one day bring about the creation of the fabled P-47. As no one thing was out of reach for such a family, one of the prizes under Seversky ownership became one of the first airplanes in the country of Russia. As such, Alexander Seversky learned to fly at an early age and a passion for all things flight and an equal passion for all things mechanical soon evolved from within. Seversky was then enrolled in military school by age 10 and went on to graduate from the Russian Imperial Naval Academy in 1914. By the time of World War 1, he was stationed aboard a destroyer as a sailor with the Russian Navy in the Baltic Sea but his first passion remained flying - and he was quite good at it. Shortly after 1915, he transferred out of the Navy and attended the Military School of Aeronautics only to return to the Russian Navy - this time as a pilot.
After his re-assignment, Seversky was installed into one of Russia's burgeoning flying squadrons. He was charged as pilot of a two-man bombers with a comrade - the observer/rear gunner - in the second cockpit. Seversky took to the air in what may have felt like a "routine" (if there's anything routine about combat) mission against German destroyers. During the initial attack, his aircraft took serious ground fire, foiling the attack and forcing the aircraft into the sea. To add insult to this mishap, the unexploded ordnance under the wings now detonated, instantly killing his observer and severely mutilating Seversky's leg. While eventually rescued, Russian doctors were forced to amputate the damage leg and Seversky's flying career was all but over.
Recovered from his wounds and now fitted with a wooden leg, Seversky set out to reclaim his former position as a flyer with the Russian air service. While his superiors balked at such a notion, Seversky illegally took to the skies in an aircraft during an aerial exhibition complete with high ranking Russian military officials in attendance. While his airborne actions proved him a sound pilot still, Seversky was promptly incarcerated for his actions but later pardoned by Czar Nicholas II. Seversky was then granted his flight status once more and was airborne in 1916. From there, Alexander Seversky went on to become the Russian Navy's leading combat ace, accruing somewhere between 6 to 13 kills (sources vary widely on this account). Leg or no leg, Seversky was going to fly as long as his heart was beating.
P-47 Thunderbolt: The Plane That Won World War II and Crushed Hitler
Key point: This spunky plane would serve in many vital roles. It could also survive better than other aircraft.
Losses were high and morale low when the U.S. Eighth Air Force intensified its heavy bomber missions over Nazi-occupied Europe in late 1942.
As the Americans persisted with their daylight offensive, complementing the Royal Air Force’s nightly raids, the air crews were eager and gallant, but misgivings mounted. The major threat came from the German fighter force, with its experienced pilots and rugged planes ready to maul the Boeing B-17 Flying Fortress and Consolidated B-24 Liberator formations.
Some planners had promised that the fabled Flying Fortress with its 10 machine guns could easily hold its own against enemy interference, but this proved to be a pipe dream. Effective escorts were desperately needed.
The first U.S. bombardment groups were accompanied to targets in France by RAF Supermarine Spitfires, but their limited range precluded them from longer forays. There was a clamor in the USAAF high echelons for the rapid development of a fighter that could stay with the bombers and fend off the Luftwaffe’s predatory Messerschmitt Me-109s and Focke Wulf FW-190s, but help was on the way.
It came from Republic Aviation Corp. of Farmingdale, Long Island, following a conference in June 1940 at which Army Air Corps leaders explained the urgent need for a high-performance fighter that could compare with European planes. One of the attendees, Republic’s brilliant, Russian-born chief designer, Alexander “Sasha” Kartveli, began work on the back of an envelope, and then he and his team drafted blueprints for an improved version of the former Seversky Aircraft Corp.’s disappointing P-43 Lancer fighter.
The result was the P-47 Thunderbolt, a big single-seat fighter powered by a 2,300-horsepower Pratt & Whitney radial engine, with a top speed of 428 miles an hour, a range of 1,000 miles, and a ceiling of about 42,000 feet. It mounted six or eight .50-caliber machine guns and could carry up to 2,500 pounds of bombs or rockets. The P-47 would prove to be one of the most effective and widely used Allied fighters of World War II.
A prototype, XP-47B, flew for the first time on May 6, 1941. In addition to the Farmingdale plant, production lines were established in Evansville, Indiana, and Buffalo, New York. Many teething problems were encountered in getting the new planes operational, and the XP-47B crashed on August 8, 1942. But deliveries of P-47B models to Army Air Forces squadrons began on March 18, 1942. The early P-47s were called “razorbacks” because of their raised rear fuselage leading to the framed cockpit hood. Several hundred of the planes went to British, Soviet, and Free French fighter units under the Lend Lease Program. The RAF used Thunderbolts extensively in North Africa, India, and Burma.
The first P-47s to see service under American colors were received in June 1942 by the Army Air Forces’ 56th Fighter Group, which, by January 1943, had joined the Eighth Air Force in Britain. It was reinforced by the 78th Fighter Group, and they began operational sorties on the following April 13. They flew their first escort mission on May 4, 1943, when the 56th Fighter Group accompanied B-17s to Antwerp.
Initial encounters with German fighters showed that, while the Thunderbolt was lacking in performance and maneuverability, it was rugged and could out-dive any other fighter. It was the first USAAF fighter to provide the sorely needed protection to the Eighth Air Force B-17 and B-24 streams.
Colonel Edward W. Anderson’s 4th Fighter Group, based at the Debden RAF station near Saffron Walden, Essex, was equipped with the new planes in March 1943. Formed the previous September from the 71st, 121st, and 133rd Eagle Squadrons of the RAF, the group’s experienced pilots, who had been blooded in graceful Spitfires, were less than enthusiastic when they climbed into the bulky Thunderbolts. The P-47 weighed almost three times as much as the British fighter, and the Eagles had doubts about its firepower—eight machine guns compared with the Spitfire’s four 20mm cannons.
Enemy kills came slowly, but the P-47 scored its first aerial victory south of Dieppe on April 15, 1943, and the American fliers came to appreciate the plane’s qualities. In fact, they soon fell in love with it. The Thunderbolt was nicknamed the “Jug” because it was thought to resemble a container for homemade whiskey.
Major (later Lt. Col.) James A. Goodson, who had joined the RAF in 1940 and downed a total of 14 German planes, said, “The P-47, in spite of its weight and size, was an amazing aircraft, and we continued to build up our score, almost in spite of ourselves.”
At Debden, Goodson checked out Captain Don Blakeslee on the Thunderbolt. Blakeslee, a bold natural flier who had piloted Spitfires with the RAF and the Eagle Squadrons since May 1941, was not impressed. “Of course, he didn’t like it,” Goodson observed. “It was daunting to haul seven tons of plane around the sky after the finger-tip touch needed for the Spit.” After his initial flight, Blakeslee griped to Flight Cmdr. James E. “Johnny” Johnson, the RAF’s leading British-born ace of the war, that the bulky, low-slung P-47 seemed reluctant to leave the ground and anxious to get back on it. It was the largest and heaviest piston-engine fighter ever to have served with the USAAF.
RAF pilots who looked over the plane shuddered and politely informed their American comrades that they were about to die. The largest single-engine fighter of the war was considered too slow and unresponsive to survive in the sky against Luftwaffe Me-109s and FW1-190s. The men of the 4th Fighter Group and other units had to be convinced otherwise by their commanders.
During a P-47 sortie over Belgium on April 15, 1943, Blakeslee blasted an FW-190 and sent it flaming into a suburb of Ostend. At the debriefing, Major Goodson told him, “I told you the Jug could out-dive them.” Blakeslee grudgingly conceded, “Well, it damn well ought to be able to dive it sure as hell can’t climb.”
Blakeslee went on to down three more FW-190s but was twice badly shot up. He eventually led the 4th Fighter Group and emerged as one of the outstanding U.S. flight leaders of the European war. In the air continually for three years, he logged more than 1,000 combat hours during 500 sorties and was awarded the Distinguished Service Cross twice.
Despite its weight and size, the P-47 proved to be a highly effective fighter that performed sterling service through the rest of the war. It was a devastating dive bomber and more than satisfactory in dogfights. Many USAAF aces in the European Theater racked up high scores in Thunderbolts. The plane could absorb considerable damage and still bring its pilot home.
Colonel Francis S. “Gabby” Gabreski of the 56th Fighter Group, who shot down 31 enemy planes while flying P-47s, reported that one of his comrades took five direct 20mm cannon hits in his right wing but still managed to return to base. During one sortie, Blakeslee’s Thunderbolt was hit by 68 cannon shells. Yet, he returned to England, escorted by Major Goodson.
Gabreski, also a veteran of RAF Spitfire squadrons, praised the P-47’s roomy cockpit, “nice” handling, and “truly spectacular” dive performance. He and the other pilots loved and trusted the plane. One flier who preferred the Thunderbolt to the sleek, elegant North American P-51 Mustang remarked, “When flying the Jug, I always felt as if I was in my mother’s arms.”
Lieutenant Will Burgsteiner of the 359th Fighter Group wrote in his diary, “We never realized we loved the old barrel and her eight guns so much.” Boyish Captain Marvin Bledsoe of the 350th Fighter Squadron, based at Raydon, Suffolk, rhapsodized, “How I loved to fly that airplane…. I felt a surge of pride that I was a member of a combat fighter squadron and was flying the most powerful fighter ship in the world…. The P-47 Thunderbolt was the hottest American fighter plane. The more I flew the Thunderbolt, the more I liked it.”
A veteran of the Normandy invasion and Operation Market Garden, Bledsoe flew 70 combat sorties in his P-47 named Little Princess,was awarded the Distinguished Flying Cross and the Air Medal with oakleaf clusters, and published a memoir, Thunderbolt,in 1982.
Among many other fliers who were impressed with the P-47 was Luftwaffe ace and Battle of Britain veteran General Adolf Galland. After flying a captured Thunderbolt, he reported that the cockpit was big enough to walk around in. A standing joke during the war was that the best way to take evasive action in a P-47 was to undo the straps and run around the cockpit. The plane’s attributes included a low internal noise level, little vibration, prompt control response, and an efficient cockpit heating system, which, unlike the Spitfire, kept the windshield clear of frost when diving.
One distinction of the P-47 was that it probably gathered more nicknames than any other Allied plane of the war. Besides the Jug, it was affectionately known by its pilots and ground crews as “Big Ugly,” “Bucket of Bolts,” “Cast-Iron Beast,” “Repulsive Scatterbolt,” “Seven-Ton Milk Bottle,” “T-Bolt,” and “Thunder Mug.”
Why The Luftwaffe Came to Hate America’s P-47 Thunderbolt
Pilots nicknamed early-model P-47 Thunderbolts the “Razorback,” a reference to the chunky fighter plane’s angular canopy.
Here's What You Need to Remember: In recognition of the Wolfpack’s achievements, a P-47M was displayed under the Eiffel Tower for a victory celebration that July. Meanwhile, Republic developed the P-47M into to the ultimate P-47N model, 1,800 of which were built.
More From The National Interest:
Pilots nicknamed early-model P-47 Thunderbolts the “Razorback,” a reference to the chunky fighter plane’s angular canopy. However, the name was more generally appropriate—like a wild boar, the hulking single-engine “Jug” was tough and hard-charging, and its eight .50 caliber machine guns packed a hell of a punch.
Lugging underwing fuel tanks, Thunderbolts based in Britain could accompany four-engine B-17 and B-24 bombers of the 8 th Air Force on dangerous raids deep over Nazi Germany—and still engage German fighters on roughly even terms, especially while diving.
However, starting mid-1944, the Allied fliers grew concerned about new Nazi turbojet-powered Me-262 fighters and rocket-powered Me-163s that could outrun the speediest Allied piston-engine aircraft like the Mustang or British Tempest by 100 miles per hour or more. V-1 “Buzz Bomb” cruise missiles bombarding London, though slower, also proved difficult for Allied fighters to intercept.
On its own initiative, Thunderbolt manufacturer Republic set aside four bubble-canopy P-47Ds from its production line in Farmingdale, New York and fit them with souped-up Pratt & Whitney R-2800-57 Double Wasp engine with a turbo-supercharger. Together, these could generate 2,800 horsepower.
At high altitude, the yellow-painted YP-47M prototypes could attain a climb rate of 3,500 feet per second and a maximum speed of 473 miles per hour in level flight—though some pilots reported achieving 490 to 500 mph when using Wartime Emergency Power. This made the P-47M arguably the fastest piston-engine fighter to see combat in the war—though still slower than the Me-262’s 540-miles per hour maximum speed.
Though Republic produced more radical XP-47H and J prototypes that could go even faster, the YP-47 could be easily put into production, so in September 1944 the Army Air Corps approved a limited run of 130 P-47M-1-RE aircraft. These were delivered in December 1944 and began to be received by their sole operator, the elite 56 th Fighter Group based at Boxted Airfield near Colchester, England on January 3.
The 56 th , better known as Zemke’s Wolfpack after its legendary first ace commander, was the only unit in the strategic-bombing-focused 8 th Air Force not to trade its Thunderbolts for P-51D Mustangs, a sleeker and more agile (though less robust) fighter. The Wolfpack’s three squadrons completed conversion to the P-47M by March, each with a unique camouflage scheme: dark black wing-tops for the 61 st , green/grey disruptive pattern for the 62 nd , and a striking blue/teal pattern for the 63 rd .
The 56 th also received new experimental T48 .50-caliber incendiary rounds designed to ignite kerosene jet fuel, which has a higher combustion temperature. The 500-grain rounds, manufactured by the Des Moines Ordnance Plant, were stuffed with 5.4 ounces of incendiary composite—twice the quantity in the standard M1 round.
However, the juiced-up engines of the P-47Ms were plagued by serious technical problems. After a Thunderbolt crash landed due to engine trouble, a crack ignition harness was discovered. Then, on February 26, a problem with the fuel carburetor diaphragm was identified, causing the P-47Ms to be grounded while a local company built new gaskets.
But these fixes didn’t bring an end to the P-47M’s woes. On an escort mission on April 4, six out of fourteen Thunderbolts had to abort mission with engine trouble. The breakdowns took a deadly turn between April 11 and 15 as three pilots were killed in engine-related accidents. The P-47Ms were grounded again on April 16 , and the Wolfpack pilots reluctantly began training on Mustangs.
Meanwhile, technicians poured over the trouble R2800-57’s engines—and discovered rust in the pistons. The super Double Wasp engines had been improperly sealed for transport across the Atlantic, allowing humid ocean air to corrode the pistons.
By March 25, replacement engines had been procured and the 56 th was back to operational status. Despite the growing paucity of Luftwaffe targets, the P-47M went on to distinguish itself performing exactly the kind of mission it had been designed for—shooting down Nazi jets.
In fact, the P-47M’s first two jet kills occurred prior to solving the corrosion problem. On March 14, three P-47s of the 62 nd fighter squadron swooped down upon two low-flying Arado 234B jet bombers. The twin-engine jet bombers were likely targeting the battered Ludendorff Bridge in Remagen over which the U.S. 1 st Army was pouring into Germany. The P-47Ms, roughly equaling the Arado’s in speed, shot down both.
Then on March 25, Wisconsinite Major George Bostwick, commander of the 63 rd Squadron, and wingman Edwin Crosthwait dispatched two Me-262s as they came in for a landing at Parchim airfield—a time at which jet fighters were notoriously vulnerable. Bostwick and his Thunderbolt “Ugly Duckling” (pictured together here) ended the war with eight air-to-air kills.
Though the Luftwaffe was increasingly crippled by a lack of fuel and trained pilots, Me-262’s still posed a deadly threat to U.S. bombers. Fifty-three Thunderbolts were escorting a raid targeting Regensburg on April 5 when a lone Me-262 came streaking in from 3 o’clock at over 500 miles per hour, zipped unscathed through a hail of defensive machine gun fire and blasted a B-17 out of the sky with its four powerful 30-millimeter cannons. The escorting Razorbacks tore after the speeding jet as it peeled away at 9 o’clock—including “Devastatin’ Deb,” piloted by Captain John C. Fahringer.
Stephen Chapis described the action in Allied Jet Killers of World War II:
“The P-47s jettisoned their tanks and headed down in pursuit. 1 st Lt. Phillip Kuhn fired first, before overshooting, after which Fahringer rolled in on the Me-262’s tail and let it have several bursts to no effect. However, the German pilot then made the fatal mistake of tightening his turn, which allowed Fahringer to close into lethal range. At 500 yards, he opened up again with this Thunderbolt’s eight .50-cal machine guns, and as the smoke began pouring from the jet Fahringer saw something go down the right side of his P-47. It was the pilot of the Me 262.”
On April 10, Lieutenants Walter Sharbo and Bill Wilkerson shot down two more Me-262s over Muritz lake while returning from a fighter sweep over Berlin. These were the last two aerial victories of the 56 th Fighter Group.
Three days later, after failing to encounter enemy fighters on an escort mission, the Wolfpack swooped down on Eggebek airfield, their chattering machine-guns expending 85,000 rounds and destroying ninety-five parked aircraft on the ground.
The new incendiary ammunition proved especially devastating. After the German surrender, an air force report enthused “…enemy aircraft burned after having been hit only two or three times. . . . One pilot destroyed 10 aircraft on a single mission by firing short bursts.” This may be referring to 2 nd Lt. Randall Murphy, whose gun camera recorded the destruction of ten aircraft during the Eggebek strike.
Zemke’s Wolfpack ended the war the top-scoring U.S. fighter group of the 8 th Air Force, with 665.5 recognized aerial kills—or one thousand aircraft destroyed, including those strafed on the ground. The P-47Ms, which served after the Luftwaffe was largely defeated, claimed only fifteen of those victories—though that included at least seven jet aircraft. Twelve P-47Ms were lost in accidents, and two shot down by ground fire, but not one fell in air-to-air combat.
In recognition of the Wolfpack’s achievements, a P-47M was displayed under the Eiffel Tower for a victory celebration that July. Meanwhile, Republic developed the P-47M into to the ultimate P-47N model, 1,800 of which were built. Though slightly slower than the P-47M due to greater weight, the N was modified to fly up to 1,800 miles on internal fuel thanks to additional tanks incorporated in the wings—a useful quality for the long-range missions it flew in the final months of the War in the Pacific.
Sébastien Roblin holds a master’s degree in conflict resolution from Georgetown University and served as a university instructor for the Peace Corps in China. He has also worked in education, editing, and refugee resettlement in France and the United States. He currently writes on security and military history for War Is Boring. This article first appeared in 2019 and is being reprinted due to reader interest.
Republic P-47 Thunderbolt - History
Republic P-47 Thunderbolt
Variants/Other Names: See History below
P-47D Serial Number 44-90460 (N9246B), named "Hun Hunter XVI," owned by Neal Melton of Luttrell, Tennessee, USA, shows of its muscular lines at the Yankee Air Museum Airshow in 2002. Photo courtesy of Richard Seaman.
History: The Thunderbolt was the most famous of all the Republic aircraft in WWII. First flown on 6 May 1941, the P-47 was designed as a (then) large, high-performance fighter/bomber, utilizing the large Pratt and Whitney R-2800 Double Wasp engine to give it excellent performance and a large load-carrying capability. The first deliveries of the P-47 took place in June 1942, when the US Army Air Corps began flying it in the European Theater.
Though it was an excellent airplane, several improvements were made as production continued, with each improvement adding power, maneuverability and range. As the war progressed, the Thunderbolt, or "Jug," as it was affectionately called, gained a reputation as a reliable and extremely tough airplane, able to take incredible amounts of damage and still return its pilot home safely. P-47s logged almost 2 million flight hours during the war, during which they were responsible for the destruction of over 7,000 enemy aircraft in the air and on the ground in the European Theater alone.
Later in the war, Jugs served as escort fighters for B-29 bombers in the Pacific. Mostly, though, they excelled in the ground-attack role, strafing and bombing their way across the battlefields of Europe. Early versions of the P-47 had "razorback" fuselages, but later models (beginning near the middle of the P-47D production run) featured a bubble canopy which gave the pilot increased rearward visibility.
P-47s were also used during the war by the air forces of Brazil, England, France, Mexico and the Soviet Union. Following the war, the Jug served for nine more years in the US, flown by the Air National Guard. It continued to serve for many additional years with the air forces of over 15 nations around the world.
Nicknames: Jug T-Bolt
Engine: 2535hp Pratt & Whitney R-2800-59W Double Wasp radial piston engine
Weight: Empty 9,950 lbs., Maximum Takeoff 17,500 lbs.
Wing Span: 40ft. 9.25in.
Length: 36ft. 1.75in.
Height: 14ft. 8in.
Maximum Speed: 433 mph
Ceiling: 41,000 ft.
Range: 1900 miles with drop tanks
Eight 12.7mm (0.5 in.) wing-mounted machine guns
Up to 2500 lbs. of externally-mounted bombs, rockets, or other free-fall ordinance
Number Built: 15,677
Number Still Airworthy: 9
[ Click for more great books about the P-47! ]
All text and photos Copyright 2016 The Doublestar Group, unless otherwise noted.
You may use this page for your own, non-commercial reference purposes only.
The P-47 Thunderbolt, or the 'Jug' as it came to be known, was a design of Georgian immigrant Alexander Kartveli, and was to replace the Seversky P-35 that was developed earlier by Russian immigrant Alexander P. de Seversky (born in the same place as Kartveli: Tbilisi, Georgia). [Note 2] Both had fled from their homeland to escape the Bolsheviks.  [Note 3]
P-43 Lancer / XP-47B
In 1939, Republic Aviation designed the AP-4 demonstrator powered by a Pratt & Whitney R-1830 radial engine with a belly-mounted turbocharger. While the resulting Republic P-43 Lancer was in limited production, Republic had been working on an improved P-44 Rocket with a more powerful engine, as well as on a fighter designated the AP-10. The latter was a lightweight aircraft powered by the Allison V-1710 liquid-cooled V-12 engine and armed with eight .50 in (12.7 mm) M2 Browning machine guns. The United States Army Air Corps (USAAC) backed the project and gave it the designation XP-47.
As the war in Europe escalated in spring 1940, Republic and the USAAC concluded that the XP-44 and the XP-47 were inferior to the Luftwaffe fighters. Republic unsuccessfully attempted to improve the design, proposing the XP-47A. Kartveli subsequently came up with an all-new and much larger fighter, which was offered to the USAAC in June 1940. The Air Corps ordered a prototype in September, to be designated the XP-47B. The XP-47A, which had almost nothing in common with the new design, was abandoned.
The XP-47B was of all-metal construction (except for the fabric-covered tail control surfaces) with elliptical wings, with a straight leading edge that was slightly swept back. The cockpit was roomy and the pilot's seat was comfortable—"like a lounge chair", as one pilot later put it. The pilot was provided with every convenience, including cabin air conditioning. The canopy doors hinged upward. Main and auxiliary self-sealing fuel tanks were placed under the cockpit, giving a total fuel capacity of 305 U.S. gal (1,155 L).
Power came from a Pratt & Whitney R-2800 Double Wasp two-row 18-cylinder radial engine producing 2,000 hp (1,500 kW)—the same engine that would power the prototype Vought XF4U-1 fighter in October 1940—with the Double Wasp on the XP-47B turning a four-bladed Curtiss Electric constant-speed propeller of 146 in (3.7 m) in diameter. The loss of the AP-4 prototype to an engine fire ended Kartveli's experiments with tight-fitting cowlings, so the engine was placed in a broad cowling that opened at the front in a "horse collar"-shaped ellipse. The cowling admitted cooling air for the engine, left and right oil coolers, and the turbosupercharger intercooler system. The engine exhaust gases were routed into a pair of wastegate-equipped pipes that ran along each side of the cockpit to drive the turbosupercharger turbine at the bottom of the fuselage about halfway between cockpit and tail. At full power, the pipes glowed red at their forward ends and the turbine spun at 21,300 rpm.  The complicated turbosupercharger system with its ductwork gave the XP-47B a deep fuselage, and the wings had to be mounted in a relatively high position. This was problematic since long landing gear was needed to provide ground clearance for the propeller. To reduce the size and weight of the long landing gear and so that wing-mounted machine guns could be fitted, each main gear strut was fitted with a mechanism by which it telescoped out 9 in (23 cm) when extended.
The XP-47B was a very large aircraft for its time with an empty weight of 9,900 lb (4,490 kg), or 65% more than the YP-43. Kartveli is said to have remarked, "It will be a dinosaur, but it will be a dinosaur with good proportions."  The armament consisted of eight .50 caliber (12.7 mm) "light-barrel" Browning AN/M2 machine guns, four in each wing. The guns were staggered to allow feeding from side-by-side ammunition boxes, each with a 350-round capacity. Although the British already possessed eight-gun fighters, the Hurricane and the Spitfire, and even the 12-gun version of the Typhoon, they used smaller-caliber 0.303 in (7.7 mm) machine guns.
The XP-47B first flew on 6 May 1941 with Lowry P. Brabham at the controls. Although there were minor problems, such as some cockpit smoke that turned out to be due to an oil drip, the aircraft proved impressive in its first trials. It was eventually lost in an accident on 8 August 1942, but before that mishap, the prototype had achieved a level speed of 412 mph (663 km/h) at 25,800 ft (7,864 m) altitude, and had demonstrated a climb from sea level to 15,000 ft (4,600 m) altitude in five minutes. 
P-47B / RP-47B and XP-47E / XP-47F
The XP-47B gave the newly reorganized United States Army Air Forces cause for both optimism and apprehension. While possessing good performance and firepower, the XP-47B had its share of teething problems:
- Its sheer size and limited ground-propeller clearance in a fuselage-level attitude made for challenging takeoffs which required long runways—the pilot had to hold the tail low until considerable speed was attained on the initial run.
- The sideways-opening canopy covers had a tendency to jam.
- The multiple-gun installation, with its tight fit and cramped ammunition belt tracks, experienced jamming problems, especially during and after hard maneuvering.
- Maneuverability was less than desired when compared with the Supermarine Spitfire and Messerschmitt Bf 109.
- The ignition system arced at high altitude.
- Access to the rear engine accessory pad was difficult due to the short engine mount used.
- At high altitude the ailerons "snatched and froze".
- At high speeds the control loads were deemed excessive.
Republic addressed the problems by fitting a rearwards-sliding canopy that could be jettisoned in an emergency, a pressurized ignition system, and new all-metal control surfaces. The deficient maintenance access to the Double Wasp radial on the B-series subtypes had to wait until the P-47C introduced a new engine mount. While the engineers worked frantically to get their "dinosaur" to fly right, the USAAF ordered 171 P-47Bs. An engineering prototype P-47B was delivered in December 1941, with a production prototype following in March 1942, and the first production model provided in May. Republic continued to improve the design as P-47Bs were produced, and although all P-47Bs had the sliding canopy and the new General Electric turbosupercharger regulator for the R-2800-21 engine, features such as all-metal control surfaces were not standard at first. A modification on the P-47B, also required for the early marks of the U.S. Navy's F4F Wildcat and F6F Hellcat was the radio mast behind the cockpit that was slanted forward to maintain the originally designed antenna wire length in spite of the new sliding canopy.
The P-47B led to a few "one off" variants. A single reconnaissance aircraft designated RP-47B was built. In September 1942, the 171st and last P-47B (41-6065) was also used as a test platform under the designation XP-47E to evaluate the R-2800-59 engine, a pressurized cockpit with a hinged canopy and, eventually, a new Hamilton Standard propeller. The plans for production were cancelled after increased emphasis on low-level operations over Europe.   Another P-47B was later fitted with a new laminar flow wing in search of higher performance and redesignated XP-47F.
In 1942 an example of the potentially 3,000 hp Fairey P-24 Monarch engine along with the Fairey Battle test bed it was installed in was shipped to Wright Field for testing with a view to possible installation in the P-47. After around 250 hours of test flying of the P-24 engined Battle at Wright Field, the idea to re-engine the P-47 with the P-24 was not subsequently proceeded with. 
Production changes gradually addressed the problems with P-47B, and on balance, with experience, the USAAF decided that the P-47 was worthwhile, and quickly followed the initial order for P-47Bs with another order for 602 more examples of an improved model, named P-47C, with the first of this variant delivered in September 1942. The initial P-47Cs were very similar to the P-47B.
Initial deliveries of the Thunderbolt to the USAAF were to the 56th Fighter Group, which was also on Long Island. The 56th served as an operational evaluation unit for the new fighter. Teething problems continued. A Republic test pilot was killed in the fifth production P-47B when it went out of control in a dive on 26 March 1942, and crashed due to failure of the tail assembly, after fabric-covered tail surfaces ballooned and ruptured.  The introduction of revised rudder and elevator balance systems and other changes corrected these problems. In spite of the problems, the USAAF was interested enough to order an additional 602 examples of the refined P-47C, with the first of the variant delivered in September 1942.
Essentially similar to the P-47B, the initial P-47C 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 P-47Cs, production moved to the P-47C-1, which had a 13 in (33 cm) 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 systems, as well as a redesigned rudder and elevator balance. The 55 P-47C-1s were followed by 128 P-47C-2s which introduced a centerline hardpoint with under-fuselage shackles for either a 500 lb (227 kg) bomb or a 200 U.S. gal (758 l, 167 Imp gal) fuel tank that conformed to the underside of the fuselage. The main production P-47C sub-variant was the P-47C-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 hp (1,716 kW). With the use of pressurized drop tanks, the P-47C was able to extend its range on missions beginning 30 July 1943. 
By the end of 1942, most of the troubles with the P-47 had been worked out and P-47Cs were sent to England. The 56th FG was sent overseas to join the Eighth Air Force, whose 4th and 78th Fighter Groups would be equipped with the Thunderbolt as well.
P-47D / P-47G and XP-47K / XP-47L
Refinements of the Thunderbolt continued, leading to the P-47D, which was the most produced version with 12,602 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-47D-15 was produced in response to requests by combat units for increased range. Underwing "wet" (equipped with fuel plumbing) bomb racks were introduced to allow a jettisonable drop tank pressurized by vented exhaust air to be carried under each wing, in addition to the belly tank. Seven different auxiliary tanks were fitted to the Thunderbolt during its career:
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.
A standardized teardrop-shaped steel tank initially produced for the P-39 Airacobra, was adapted to the P-47 beginning 31 August 1943. It was initially carried on the belly shackle, but was used in pairs in 1944 as underwing tanks, and adopted as a standard accessory in the US inventory.
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
A steel tank first used as a belly 20 February 1944, and an underwing tank 22 May 1944
A wide, flat steel tank developed by VIII Service Command was first used in February 1945.
This tank, produced by Lockheed, could be used either as a fuel tank or as a napalm container.
This tank was similar in shape to the 75 gallon drop tank, but was larger. It could also be used as a napalm container.
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, 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 their paper tanks for some reason were required to drop them into a designated "dump" area at their respective fields, resulting in substantial losses of aviation fuel.
The P-47D-16, D-20, D-22 and D-23 were similar to the P-47D-15 with minor improvements in the fuel system, engine subsystems, a jettisonable canopy, and a 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 ft (3.96 m) and the Long Island plant using a Hamilton Standard propeller with a diameter of 13 ft 2 in (4.01 m). With the bigger propellers having barely 6 in (152 mm) 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. A modification to the main gear legs was installed to extend the legs via an electric motor (un-extending before retraction) to accommodate the larger propeller diameter.
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. The Curtiss plant experienced serious problems and delays in producing Thunderbolts, and the 354 Curtiss-built fighters were relegated to stateside 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 P-47C-1, while the following P-47G-5, P-47G-10, and P-47G-15 sub-variants were comparable to the P-47D-1, P-47D-5 and P-47D-10 respectively. Two P-47G-15s were built with the cockpit extended forward to just before the leading edge of the wing to provide tandem seating, designated TP-47G, essentially to provide a trainer variant. 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).
All the P-47s produced 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 type of canopy 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 P-51 and the Thunderbolt. The first P-47 with a bubble canopy was a modified P-47D-5 completed in the summer of 1943 and redesignated XP-47K. Another older P-47D was modified to provide an internal fuel capacity of 370 U.S. gal (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 P-47D (rather than a new variant designation). First deliveries of the P-47D-25 to combat groups began in May 1944.
It was followed by similar bubble-top variants, including the P-47D-26, D-27, D-28 and D-30. Improvements added in this series included engine refinements 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 fin running from the vertical tailplane to just behind the radio aerial. The fin fillet was retrofitted in the field to earlier P-47D bubble-top variants. The P-47D-40 also featured provisions for 10 "zero length" stub launchers for 5 in (127 mm) High velocity aircraft 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 P-47s were nicknamed "Superbolts" by combat pilots in the field. 
XP-47H / XP-47J
Republic made several attempts to further improve the P-47D:
Two XP-47Hs were built. They were major reworkings of existing razorback P-47Ds to accommodate a Chrysler IV-2220-11 water-cooled 16-cylinder inverted vee engine. The plane went over 500 mph [ citation needed ] , but, with the end of the war, it never saw production.
The XP-47J began as a November 1942 request to Republic for a high-performance version of the Thunderbolt using a lighter airframe and an uprated engine with water injection and fan cooling. Kartveli designed an aircraft fitted with a tight-cowled Pratt & Whitney R-2800-57(C) with a war emergency rating of 2,800 hp (2,090 kW), reduced armament of six 0.50 in (12.7 mm) machine guns, a new and lighter wing, and many other changes. The only XP-47J was first flown in late November 1943 by Republic test pilot Mike Ritchie. Less than a year later it flew into the aviation history books marking a new milestone for speed.  [ page needed ]
When fitted with a GE CH-5 turbosupercharger, the XP-47J achieved a top speed of 505 mph (440 kn, 813 km/h) in level flight on August 4, 1944 at 34,500 feet over a course in Farmingdale, NY. No piston engine airplane of the WWII era ever flew faster than the speed attained by test pilot Mike Ritchie in the XP-47J. It took nearly half a century for that speed record to be approached again in a piston engine aircraft. On August 16, 1989, Darryl Greenamyer piloted his highly modified Grumman F8F Bearcat to a new FAI certified official world speed record of 483 mph for a piston engine over the course at Edwards Air Force test center. Ritchie's speed record in the P-47J was not exceeded until August 21, 1989 when Lyle Shelton piloted a different modified Grumman Bearcat (with a larger Wright R-3350 Duplex Cyclone engine) and set a new official FAI record at 523.586 mph.
The P-47M was a more conservative attempt to come up with a higher-performance ("Sprint") version of the Thunderbolt, designed to chase V-1 flying bombs, done, in part, by reducing armament from eight .50-caliber Colt-Browning M2 machine guns to six.  In September 1944, four P-47D-27-RE airframes (s/n 42-27385 / 42-27388) were modified into prototype YP-47Ms by fitting the R-2800-57(C) engine and the GE CH-5 turbo-supercharger, a combination which could produce 2,800 hp (2,089 kW) at 32,500 ft (9,900 m) when using Wartime Emergency Power (water injection). Air brakes were added to the wing's lower surfaces to allow braking after a dive onto its prey. The YP-47M had a top speed of 473 mph (410 kn, 761 km/h) and it was put into limited production with 133 (sufficient for one group) built. However, the type suffered serious teething problems in the field due to the highly tuned engine. Engines were unable to reach operating temperatures and power settings and frequently failed in early flights from a variety of causes: ignition harnesses cracked at high altitudes, severing electrical connections between the magneto and distributor, and carburetor valve diaphragms also failed. Persistent oil tank ruptures in replacement engines were found to be the result of inadequate protection against salt water corrosion during transshipment. In the end, it was simply errors made by the R-2800-57(C) model engine's manufacturers which led to these issues with the P-47M. By the time the bugs were worked out, the war in Europe was nearly over. However, P-47Ms still destroyed 15 enemy aircraft in aerial combat, normal results for any fighter type in March–May 1945 when aerial encounters with the Luftwaffe were rare. The entire production total of 130 P-47Ms were delivered to the 56th Fighter Group, and were responsible for all seven of that group's jet shoot-downs. Twelve were lost in operational crashes with the 56th Group resulting in 11 deaths, two after VE Day, and two (44-21134 on 13 April 1945 and 44-21230 on 16 April 1945) were shot down in combat, both by ground fire.
The second YP-47M (of the batch of four converted P-47Ds) was later fitted with new wings and served as the prototype for the P-47N.
The P-47N was the last Thunderbolt variant to be produced. It was designed as an escort fighter for the Boeing 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. gal (190 l) fuel tanks. The second YP-47N with this wing flew in September 1944. The redesign proved successful in extending range to about 2,000 mi (3,200 km), and the squared-off wingtips improved the roll rate. The P-47N 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-47N-25, rolled off the production line in October 1945.
At the end of production, a Thunderbolt cost $83,000 in 1945 U.S. dollars. A total of 15,678 Thunderbolts of all types were built. 
Republic P-47 Thunderbolt - History
By Sam McGowan
Since the end of World War II, the aviation press has made the North American P-51 Mustang into the superstar Allied fighter of the war. In reality, however, the Republic P-47 Thunderbolt aircraft was the most widely used U.S.-built fighter, and in many respects it was the most capable. During the last year and a half of the war, P-47s represented nearly half of all U.S. Army fighters in overseas groups.
It was the P-47, along with the longer range Lockheed P-38 Lightning, that gained air superiority for the Allies in the skies over Western Europe. The P-47 was the second most popular fighter in the Pacific Theater, and it was the Thunderbolt that came to personify the fighter-bomber, a concept that still dominates the United States Air Force.
Development of the P-47 Thunderbolt Aircraft
The Thunderbolt was Republic Aircraft’s entry into the 1940 competition for an American-built fighter that would be capable of holding its own against the German fighters that dominated the air war then taking place over Europe. Based in Farmingdale, New York, Republic Aircraft was the successor to the company Russian-born aircraft designer Alexander de Seversky had founded in 1935. Seversky had designed the first modern American fighter, the Seversky P-35, and followed it with the P-43 Lancer, a design that was never purchased by the U.S. Army. In 1939, four years after founding the company, Seversky fell victim to corporate maneuvering when he was voted off the company’s board. He was in Europe at the time, trying to interest the British in his design ideas. The new leaders changed the name of the company to Republic Aircraft.
Republic’s initial venture into the fighter design game was a small, lightweight fighter built around the Allison V-12 engine. Designer Alexander Kartveli, who had worked closely with Seversky on the company’s previous designs, was put in charge of the project. When the Army voiced concern about the demand on the liquid-cooled engines, Republic’s attention turned toward the air-cooled Pratt & Whitney Double Wasp R2800 engine, which produced more than 2,000 horsepower—but which also consumed nearly twice as much fuel as the Allison.
/>Profile view of the Republic P-47 Thunderbolt aircraft.
Kartveli “borrowed” from Seversky’s previous radial engine designs and came up with a design that incorporated many of the features of the P-43. The more powerful engine allowed Republic to increase the weight of its fighter design dramatically, making it the heaviest single-seat fighter built up to that time. One of the laws of aircraft performance is that rate of climb is in direct relation to the excess power available at a particular airspeed. The increased weight of the XP-47 gave the airplane a slower rate of climb than was really needed for an interceptor. However, by the time the P-47 entered combat, the necessity for interceptors had begun to decline and the heavy weight of a Thunderbolt aircraft gave the airplane other desirable features, such as increased speed in a dive and resistance to damage from gunfire.
The Thunderbolt is one airplane that truly deserves the often overused adjective “rugged.” The air-cooled engines were less susceptible to engine failure in combat since there was no coolant to be lost to leaks caused by battle damage.
Deploying the Thunderbird Aircraft with the 56th Pursuit in 1942
The first U.S. Army operations group to fly the P-47 was the 56th Pursuit Group, which was conveniently based in the vicinity of the Republic factory at Farmingdale—in fact, one squadron was right there on the field. The others were at Bridgeport, Connecticut, and Bendix, New Jersey. Initially equipped with Bell P-39s and Curtiss P-40s, the 56th began receiving P-47s in the spring of 1942, the initial deliveries nearly coinciding with the assignment of Captain Hubert “Hub” Zemke to the group after he returned from an overseas tour as an observer in Russia. Zemke’s name and the P-47 would become forever linked.
It was not until early 1943, more than a year after the U.S. Army Air Corps entered combat, that the first P-47s arrived overseas. Previously, the burden of fighting the Axis had fallen to the P-39s and P-40s in the Pacific and the P-38, P-40, and British Supermarine Spitfire and Hawker Hurricane in Europe and North Africa. The first American fighters sent to England were Lockheed P-38s, but the war in North Africa sucked them all out of the British Isles, leaving only Spitfires to escort B-17 and B-24 bombers on missions over occupied Europe.
The nimble Spitfire had earned a reputation as an outstanding fighter during the Battle of Britain in 1940, but it lacked the range to go with the bombers on the long raids and was thus ineffective as an escort fighter. In fact, Spitfires were only capable of going a few miles east of the English Channel without extended-range fuel tanks. Even with the tanks, their range was limited. The veteran 56th, which had been re-designated as a fighter group, arrived in England in early 1943 but did not go into combat until April. The VIII Fighter Command decided that the airplane needed modifications—including additional armor—and the pilots needed combat training before they entered the fray.
When the 56th Fighter Group arrived in England, there were already two fighter groups there. The 78th Fighter Group had gone overseas with P-38s, but it lost them and most of its pilots to North Africa—leaving the remaining pilots without airplanes—and began re-equipping with Thunderbolts, as did the 4th Fighter Group. The 4th Fighter Group was made up of American Eagle Squadron pilots who had volunteered to fly with the British Royal Air Force before America entered the war, and to a man they all loved the Spitfire and came to hate the Thunderbolt, almost with a passion. Like their British cousins in the RAF, the young Americans thought the Spitfire was the best fighter ever built, an idea that was more truthful in spirit than in actual merit. They were not happy that they were giving up their light and maneuverable steeds for the heaviest fighter in the world.
A “Jug” and a “Milk Bottle”Lieutentant Colonel Hubert Zemke commanded the famed 56th Fighter Group, known as the Wolfpack, in the European Theater. A number of 56th pilots became aces flying the P-47.
The pilots in the 4th Fighter Group started referring derisively to their new birds as “seven-ton milk bottles” in reference to the shape of the fuselage. It was not the P-47’s milk jug shape that gave the airplane its name, however, contrary to the assertions of some writers. Many of the pilots believed they were to be sacrificed and started referring to the P-47 as a “Juggernaut,” a moniker that was naturally shortened to just plain “Jug.”
The first Thunderbolt missions were advanced training flights flown over German-occupied territory as theater orientation for the pilots. Initially, the German fighter pilots paid little attention to the Allied fighter formations. Their interest was in the bombers. It was not until April 15, 1943, that the P-47s had their first encounter with German fighters. Don Blakeslee, a former Eagle Squadron pilot now with the 4th Fighter Group, managed to sneak up on a Focke-Wulfe Fw-190 in a dive and shot it down.
Diving was the P-47’s best asset. The heavier weight and huge, powerful engine allowed the airplane to accelerate rapidly. Nevertheless, Blakeslee’s comments about the airplane were less than enthusiastic. He reportedly said, “It oughta dive, it sure can’t climb.” The mission results were tilted against the Thunderbolts. One was shot down and two others lost to engine failure, a problem that was all too common during early P-47 operations. Thunderbolts were not the only U.S. fighters plagued with engine problems during their introduction to combat. Both the P-38 and P-51 suffered high engine failure rates until problems were identified and rectified.
Getting the P-47 to Berlin
On May 4, 1943, the P-47s were assigned to their first escort mission when 117 Thunderbolts from all three groups were sent to escort B-17s and B-24s attacking Antwerp and Paris. Fighter escort would be the primary mission for the Thunderbolts for the remainder of 1943. Unfortunately, even though the P-47s had a much greater range than the RAF Spitfires and Hurricanes, they still lacked the range to go deep into Germany. The Luftwaffe simply massed its fighter strength inside Germany and waited until the Allied fighter escorts had reached the limit of their range, then struck the bombers. During the summer of 1943, B-17 losses began to mount to the point that the Eighth Air Force temporarily abandoned daylight deep-penetration missions into Germany.
The only immediate solution to the problem was to extend the range of the P-47s, which at the time were the only fighters available, at least until P-38s could be sent to England. Their range was limited by the amount of fuel the airplanes could carry, so the solution was to increase fuel capacity. The use of external tanks, often called drop tanks because they could be jettisoned, was the simplest means of extending the operational range of the fighters. Initial efforts to develop external tanks met with problems. The resin-impregnated, paper tanks leaked and could not transfer fuel at high altitudes because they were not pressurized.
Lieutenant Colonel Cass Hough, the officer in charge of flight testing for VIII Fighter Command, developed a means of pressurizing the tanks using the airplane’s vacuum system. The first tanks carried only 75 gallons, and there was a problem with availability. To alleviate the problem of supply and demand, the VIII Fighter Command adopted British-developed paper tanks that could hold 108 gallons of fuel, which allowed the Thunderbolts to go 325 miles into occupied territory. It still was not enough to take them all the way to Berlin.
One solution for extending the Thunderbolt’s range was to equip the airplane with partially filled unpressurized 200-gallon external drop tanks and use their contents during the climb to altitude. This was an aerodynamically sound practice that allowed the fighters to take advantage of the slower airspeeds—and lessened parasitic drag—in the climb. The procedure allowed the Thunderbolts to arrive at altitude without the drop tanks but with nearly full internal fuel tanks and clean wings, which allowed higher speeds and increased range. This technique initially caught the German fighter pilots by surprise and resulted in some victories for the Thunderbolt aircraft pilots.
Thunderbolt Aircraft in the Pacific
Flying above the island of Luzon in the Philippines, P-47 Thunderbolts of the Mexican 201st Fighter Squadron wing their way toward a Japanese target.
While the 4th, 56th, and 78th Fighter Groups were entering combat with P-47s in Europe, the 348th Fighter Group was on its way to the Southwest Pacific to join the famous Fifth Air Force. Unlike the VIII Fighter Command, which participated in very little combat in 1942, V Fighter Command pilots had been battling the Japanese since early 1942. Some pilots had even been in the Philippines when the war broke out and had been in combat since the beginning.
When the group arrived, Fifth Air Force commander Lt. Gen. George C. Kenney hit on a scheme to build the morale of the new arrivals and to afford the veterans, particularly the P-38 pilots, a measure of respect for the heavy Thunderbolt. He orchestrated a mock dogfight between the 348th commander, Lt. Col. Neel Kearby, and Major Tommy Lynch, who at the time was the highest scoring ace in the Fifth Air Force. The night before the fight, Kenney pulled Kearby aside and told him to lay off the booze and go to bed early, while knowing that Lynch would do just the opposite. The next morning Kearby showed the stuff that would put him among the top-scoring fighter pilots of the war. The P-47 pilots got a boost in morale and the P-38 pilots decided that the new arrivals would be an asset to the New Guinea campaign after all, rather than the liability they had imagined them to be.
Kearby and his pilots adopted tactics that had been used successfully by P-40 pilots against the Japanese, which included attacking in a dive, then breaking away from the enemy formation and refusing to engage the lightweight and highly maneuverable Japanese fighters in a dogfight. Kearby taught his men to use the inertia from their dives to zoom right back up to altitude for another attack. Similar techniques were also adopted in Europe.
The long, overwater legs required for combat in the Pacific dictated the need for increased range, and drop tanks were a high priority. Of all of the American combat units of World War II, the Fifth Air Force was undoubtedly the most innovative, and it had an engineering department at Brisbane that was second to none. There were 110-gallon tanks available that had been initially developed for P-39s and P-40s, but V Fighter Command wanted more capacity. The Fifth Air Force depot went to work on the problem and came up with a 200-gallon, low-profile tank that filled the bill.
What Made the Thunderbolt a Successful Dog Fighter
In spite of their limited range in comparison with the P-38s, the P-47s proved to be a successful fighter in the Pacific. Thunderbolts replaced the P-40 and P-39 in the veteran 35th and 49th Fighter Groups and in one squadron of the 8th Group. Some V Fighter Command pilots were not enthused about the Thunderbolt, but others were. Lt. Col. Neel Kearby was undoubtedly the leading P-47 pilot in the theater and one of the top-scoring aces of the war. Unfortunately, he contracted “Bong fever,” a condition that caused a fighter pilot to become obsessed with catching up and passing the score of the American ace of aces, Major Dick Bong, who had replaced Tommy Lynch at the top of the heap when Lynch was killed in action.
A Thunderbolt aircraft of the Mexican 201st Fighter Squadron flies in formation above Clark Field in the Philippine Islands. Note the bomb attached to the hard point beneath the fuselage.
Kearby drove himself to shoot down Japanese planes, as did many other American aces. Although the competition no doubt led to the destruction of countless numbers of Japanese planes, it also caused the young fighter pilots to take dangerous risks, and many lost their lives. Kearby died when he was apparently shot down in a dogfight in May 1944 after he led his wingmen in an attack on a formation of Kawasaki Type 48 bombers. Kearby shot down one, and his wingmen each got another. Then they were jumped by a flight of aggressive Japanese fighters, and Kearby was shot down. He was last seen hanging in his parachute, but he was never heard from again. The wreckage of his airplane was found in March 1946.
P-47s were second only to the Lockheed P-38 Lightning in the Southwest Pacific area of operations. While the longer range of the P-38 made the Lightning the fighter of choice for bomber escort missions deep into Japanese territory, P-47s pulled their share of the load by maintaining combat air patrols over Allied airfields and escorting transports and light and medium bombers on shorter range missions. It was in New Guinea that the Army Air Forces began developing tactics to provide close air support to ground troops, and P-47s were soon adapted to this role as well as air-to-air combat.
Lindberg’s Fuel Management Techniques
The lack of range of the P-47 Thunderbolts was due in large measure to the operating procedures in use in the Army Air Corps. Pilots were taught to operate their airplanes at high RPMs and high manifold pressure and were told that leaning the mixture too much could damage the cylinders. While this was essentially true, most pilots failed to lean as much as they could have and thus consumed fuel at a high rate. In the summer of 1944, the famed aviator Charles Lindbergh visited the Southwest Pacific during a fact-finding tour as a factory representative for United Aircraft, a builder of the Vought F4U Corsair fighter. Previously, Lindbergh had worked as an unpaid consultant with Ford Motor Company, where he became involved with the Thunderbolt, particularly in his research on high-altitude flight.
Lindbergh became intimately acquainted with the P-47 and was shocked beyond belief when he arrived in the Pacific and discovered that the Army pilots were using techniques that led to drastically high fuel consumption. When he returned to New Guinea after a visit with General Kenney in Brisbane, Lindbergh ferried a P-47 back to the forward area. A base operations officer, who was an experienced P-47 pilot, refused to approve his flight plan, which called for a nonstop flight from Brisbane to New Guinea. But Lindbergh knew exactly how much fuel he was going to use and arrived with fuel to spare, a feat that amazed the young Army pilots.
Soon, Lindbergh was teaching his fuel management techniques to P-38 and P-47 pilots and helping increase the effective combat range of V Fighter Command. Lindbergh knew that by reducing propeller RPMs while maintaining manifold pressure, fuel consumption would be reduced and an airplane’s range would be increased considerably.
The P-47 in the Ground Attack Role
In early 1944, Thunderbolts began appearing in the skies over China. The first P-47 group in the China-Burma-India Theater was the 33rd Fighter Group, a historic group that started out in combat in North Africa flying P-40s, then transferred to the Asian theater after the Sicily campaign. The 33rd was joined by the 81st Fighter Group, which had also entered combat in North Africa with P-39s.
A P-47 of the U.S. Ninth Air Force destroyed a German ammunition truck in a ball of fire on August 15, 1944.
The two groups transferred to the CBI as part of a deployment of several combat groups from the Mediterranean to India to support British Brigadier Orde Wingate’s Chindit expedition into Burma. While the 33rd was equipped with both P-47s and P-38s, the 81st was an all-Thunderbolt outfit from the time the group arrived in India in February. The 80th Fighter Group began combat operations in the CBI with P-40s and P-38s, then equipped with Thunderbolts in the spring of 1944. The 33rd Group flew P-47s only until November 1944, when it became an all-P-38 outfit. The 1st Air Commando Group, a composite unit that was organized in India in early 1944, included two fighter squadrons that started out with an older version of the North American P-51, then transitioned into P-47s later in the year.
Thunderbolts were also active in the Central Pacific. Because of the long distances between land bases in the region, the first P-47s to see duty in the Marianas arrived aboard the escort carriers Manila Bay and Natoma Bay. They were from the 318th Fighter Group, which transferred to Micronesia from Hawaii. Although the convoy, including the two carriers, was attacked by Japanese dive-bombers, all 111 P-47s were delivered to Aslito Airfield on Saipan, where they immediately went into action in support of the ground forces that had invaded the island.
Close air support of ground troops started in the Southwest Pacific in the summer of 1942, when modified Douglas A-20 Havoc light bombers began strafing Japanese positions opposing Australian troops on the Kokoda Track in Papua, New Guinea. General Kenney was so impressed with the tactics that he instructed the fighter groups under his command to develop ground attack tactics as well.
When American forces landed in North Africa in late 1942, Twelfth Air Force commander Lt. Gen. James H. Doolittle restricted the light and medium bombers to medium altitude attack and assigned the close air support role to the fighters because German air opposition was declining. RAF pilots taught the Americans the intricacies of close air support.
The success of the fighter bomber in the Southwest Pacific and North Africa led to the development of ground attack tactics within the fighter commands of all of the numbered air forces—with one exception. Air Corps doctrine called for each numbered air force—which was equivalent to an army—to be multifunctional, with fighter, bomber, and troop carrier commands. The exception was the Eighth Air Force, which had switched from the multifunctional role to a single-purpose command when most of its fighter groups and all of its troop carrier groups were sent to North Africa in 1942. Daylight precision bombing had become the mission of the Eighth, and the role of VIII Fighter Command was to ensure that the bombers got to and from their targets. With no Allied ground troops in occupied Europe, there was no one for whom to provide close air support.
The VIII Fighter Command did, however, begin developing tactics for ground attack against locomotives, airfields, and other targets. The first VIII Fighter Command strafing attack actually came about by accident when a P-47 pilot suffered damage and was forced down to low altitude over France he strafed a locomotive during the flight back to England. In early 1944, VIII Fighter Command fighters began dropping down on the deck to shoot up Luftwaffe airfields and other targets after their escort missions had been completed.
In March 1944, VIII Fighter Commander Brig. Gen. Bill Kepner authorized the establishment of a special squadron of P-47s to develop strafing techniques. For a month, pilots from four groups experimented with low-level mock raids on their own airfields then they carried out operations in France. They would go in high and then dive down to treetop altitudes while about 20 miles from their target, so as to be at strafing altitude about five miles out. On April 12, the special unit disbanded and the pilots returned to their groups to teach their squadron mates the new tactics. The VIII Fighter Command began scheduling regular fighter sweeps.
Ground Attack in Western Europe
Their invasion stripes prominently displayed, Republic P-47 Thunderbolt fighter planes are prepared for action on D-Day.
After the defeat of the Germans in North Africa and the invasions of Sicily and Italy, the Allies began turning their attention toward an invasion of Western Europe, and close air support of ground troops would be a major mission for the Army Air Forces. Planning for the invasion called for the transfer of the Ninth Air Force from the Mediterranean to England to become a tactical air force, along with the creation of a new Fifteenth Air Force to control the heavy bombers operating from Italy.
The plan also included the conversion of the Twelfth Air Force to the tactical role. By early 1944, P-47s were being turned out at an unprecedented rate, and many of the new fighter groups were equipping with them. At the same time, however, a redesigned version of the North American P-51 Mustang fighter was proving suitable for the long-range escort mission, and the P-47 units that were destined for the Eighth Air Force began converting to the P-51 before they went overseas. Consequently, the Army Air Forces began assigning P-47 groups to the newly organized XVIII Tactical Air Command of the Ninth Air Force.
Early 1944 saw a major shift in strategy in Europe as the Eighth Air Force was placed under the direct command of the Supreme Allied Commander, U.S. Army General Dwight D. Eisenhower. Eisenhower decreed that the destruction of the German air force was the main priority of the Air Corps, a decision that led to a switch in tactics by the VIII Fighter Command from fighter escort to fighter sweeps, including ground attack. The Allied air commanders wisely came to realize that an enemy aircraft destroyed was an airplane destroyed, regardless of whether the destruction took place in air-to-air combat or during a strafing or bombing attack on a fighter field.
This was a principle that the Fifth Air Force in the Southwest Pacific—whose fighter pilots had been shooting down Japanese fighters and bombers at a far greater rate than their peers had been doing in Europe—adopted in 1942. Kenney could have cared less if his fighter pilots shot down enemy planes in the air or whether they were knocked out on the ground. Finally, nearly a year and a half after Kenney adopted this tactic, air commanders in Europe were forced to do the same. The P-47 would become the centerpiece for ground attack in Europe. While it was highly effective, the ground attack role was hazardous for both plane and pilot, and many Thunderbolts were lost to German antiaircraft fire.
The Making of a Formidable Fighter-Bomber
The P-47N, with squared wingtips, was developed by Republic Aviation in cooperation with the Air Technical Service Command. The Design progressed from the drawing board to production in a remarkable 56 days.
The eight .50-caliber guns in the wings of the Thunderbolt were lethal enough, but the Air Corps developed new weapons to bolster the destructive power of the fighter-bombers. Hard points were installed to allow the carrying of high-explosive bombs or tubes for firing high- velocity aerial rockets, a U.S. Navy development that was adopted by the Army. Napalm, a jellied gasoline mixture, was used to firebomb enemy troop concentrations.
Operating down on the deck, the fighter- bombers, which included P-38s and P-51s as well as P-47s, attacked enemy airfields, locomotives, and trucks. Fighter-bombers operated in close support of ground forces, attacking enemy troop and tank columns and artillery positions. The fighter-bomber concept proved so destructive that in China, where every drop of fuel had to be transported by air across the Himalayas from India, the B-24s that had been used in the strategic role were taken off combat operations and assigned to transport duty. The reasoning was that the fuel they consumed could be put to better use moving fuel for the fighter-bombers.
P-47 Thunderbolts served with many nations, including Brazil and Mexico. The British Royal Air Force operated Thunderbolts in Asia. Thunderbolts equipped six fighter groups of the French Air Force after the defeat of the Vichy French in North Africa.
Although the accomplishments of the Thunderbolts have been overshadowed in the postwar media and press by the more glamorous Mustangs, the fighters that came to be known as Jugs performed admirably throughout the last three years of World War II. If the term “yeoman” should be applied to any Allied fighter of World War II, the Thunderbolt aircraft well deserves the title.
Sam McGowan is a licensed pilot and a resident of Missouri City, Texas. He is a frequent contributor to WWII History Magazine.
Didn’t the P-47 get a new prop somewhere in its development that made it much faster?
Republic P-47 Thunderbolt
By Stephen Sherman, Apr. 2002. Updated January 24, 2012.
R obert S. Johnson and the P-47
When Robert S. Johnson first saw a Thunderbolt, it was love at first sight. The P-47B was a giant with a 2,000 horsepower engine not very pretty on the ground, but every inch a powerful machine, rugged and sturdy with all the mass of a tank. He scrutinized the tremendous four-bladed propeller. In each wing rested four 50 caliber machine guns, giving the Thunderbolt the ability to throw 7,200 rounds of lead per minute!
He had a chance to check out the P-47 at Bradley Field:
I hit the starter switch. Deep inside her belly the Thunderbolt groaned, a straining rumble sounding for all the world like a giant dynamo coming alive. Ahead of me the four propeller blades turned slowly, then began to move faster as the Pratt & Whitney gained in power. The rumble increased in pitch, the blades became a blur. Suddenly the cranking and rumbling vanished, to be replaced by a tremendous, throaty roar, a bass of power such as I'd never heard. I cracked the throttle forward a fraction of an inch and the fighter sang of power, a symphony of thunder, alive and ready to howl at the slightest movement of my fingers.
He took the plane up, nearly killing himself when the heavy canopy bar slid back and smashed his head. But he got the ship in the air and it howled its way up into the sky. He soon learned that "unless we plunged nose first into the ground, we couldn't hurt the Thunderbolt". It could take the stress of any aerobatic maneuver. The pilots of the 56th Fighter Group grew to trust the fighter, knowing they could subject it to any demands of aerial combat.
After he arrived in England in early 1943, he saw his first Spitfire and compared it to the Thunderbolt. The differences were amazing. The P-47 was a giant, massive weapon the English fighter was lithe and rapid, with the agility to dart in and out of battle. The RAF pilots warned the Americans that their huge Thunderbolts would be sitting ducks against the Messerschmitts and Focke Wulfs. They were wrong. The tough Thunderbolts more than held their own against the Luftwaffe.
One day in late June, 1943, Johnson's Thunderbolt was hit early in the mission and then helplessly subjected to an Fw 190's machine gun fire on the way home. You read about this famous story in the Robert S. Johnson article on this site. Somehow, incredibly, the P-47 absorbed this battering from the German guns and made it back. After the injured Johnson had landed his plane at the Manston emergency strip, he surveyed the damage it had taken, and later described the result in his autobiography, Thunderbolt!:
There are twenty-one gaping holes and jagged tears in the metal from exploding 20mm cannon shells. I'm still standing in one place when my count of bullet holes reaches past a hundred there's no use even trying to add them all. The Thunderbolt is literally a sieve, holes through the wings, fuselage and tail. Every square foot, it seems is covered with holes. There are five holes in the propeller. Three 20mm cannon shells burst against the armor plate, a scant inch away from my head. Five cannon shell holes in the right wing four in the left wing. Two cannnon shells blasted away the lower half of my rudder. One shell exploded in the cockpit, next to my left hand this is the blast that ripped away the flap handle. More holes appeared along the fuselage and in the tail. Behind the cockpit, the metal is twisted and curled this had jammed the canopy, trapping me inside.
The airplane had done her best. Needless to say, she would never fly again.
Johnson had great success with the Thunderbolt, shooting down 27 German planes over Europe while flying the rugged fighters.