Republic P-47 Thunderbolt

The Thunderbolt grew out of a single overriding requirement: to exploit the powerful new Pratt & Whitney R-2800 Double Wasp radial and its turbo-supercharger, which gave superb performance at high altitude. Designer Alexander Kartveli at Republic essentially built the airframe around the engine and the long ducting the turbocharger demanded, accepting great size and weight as the price of altitude performance and firepower.

First flown on 6 May 1941, the result was the largest and heaviest single-engine fighter of the war — nearly twice the weight of a Spitfire, at over 7 tons loaded. Pilots nicknamed it the “Jug,” and its sheer bulk first inspired scepticism. But it made more than 430 mph (690 km/h) at altitude, was blisteringly fast in a dive, and carried eight .50-calibre machine guns; once its teething troubles were cured, it proved a war-winner.

The first major operational versions were the framed-canopy “razorback” models, which escorted the Eighth Air Force’s heavy bombers into Germany until the longer-legged Mustang took over the deepest missions. Their weakness was rearward vision, blocked by the raised spine behind the cockpit — a real handicap in a turning fight.

The decisive refinement came with the bubbletop D-25, whose cut-down rear fuselage and frameless sliding canopy gave the all-round view a fighter pilot needed. Later M and N models added power, speed and range. Throughout, the design philosophy held constant: an air-cooled radial with no vulnerable coolant system, wrapped in enough structure and armour to bring its pilot home from damage that would have downed any liquid-cooled fighter.

The Thunderbolt’s fighting reputation was made over Europe by the 56th Fighter Group — “Zemke’s Wolfpack,” after its commander Hubert “Hub” Zemke — the only Eighth Air Force group to fly the P-47 from first to last rather than convert to the Mustang. Its pilots learned to fight the heavy fighter to its strengths: keeping their altitude, diving on the enemy from above, and using the Jug’s colossal speed in the dive to break off at will.

The Wolfpack became the highest-scoring fighter group in the Eighth Air Force for air-to-air kills, and produced the two top American aces in Europe: Francis “Gabby” Gabreski with 28 aerial victories and Robert S. Johnson with 27. Johnson’s name became inseparable from the day an Fw 190 caught his Thunderbolt from behind and emptied its guns into it — cannon shells and bullets raking the fuselage — and still could not bring it down. He flew the shredded fighter home, a public proof of the survivability the whole design had been built around.

The Thunderbolt began its combat career as a high-altitude bomber escort, carrying the fight to the Luftwaffe over occupied Europe and Germany before the Mustang assumed the very-long-range role. But it found its true calling closer to the ground. In the wake of the Normandy invasion, the P-47 became the scourge of the German army across France and the Low Countries.

Roaming at low level, its eight heavy machine guns, up to 2,500 lb (1,130 kg) of bombs and underwing rockets shredded trains, vehicles, armour and troops, guided onto targets by forward controllers in the “cab rank” system. Its knack for bringing pilots home on a shattered engine — sometimes with whole cylinders shot away — made it almost unkillable in the flak-heavy world of ground attack. In the Pacific, late-war P-47Ns ranged enormous distances to escort B-29s to the Japanese home islands.

The statistics of the Thunderbolt’s war are staggering. P-47s flew about 546,000 combat sorties between 1942 and 1945, dropped some 132,000 tons of bombs and fired over 135 million rounds of .50-calibre ammunition, claiming roughly 3,750 enemy aircraft in the air and 3,300 on the ground.

In the last year of the war in Europe, Ninth Air Force Thunderbolts were credited with destroying on the order of 9,000 locomotives, 86,000 railway wagons and 6,000 armoured vehicles. Through all this the loss rate ran below 0.7% per sortie — remarkable for an aircraft that spent its days inside the envelope of German light flak.

With about 15,600 built, the P-47 was the most-produced American fighter of the war. The line ran from the early B, C and D razorbacks through the definitive bubble-canopy D-25 to the high-performance P-47M — rushed into service to run down V-1 flying bombs and German jets — and the long-range P-47N built for the Pacific.

The Thunderbolt also flew with the RAF in Burma, the Free French, the Soviet VVS via Lend-Lease, and the Brazilian and Mexican squadrons that fought alongside the Americans. Redesignated F-47 after the war, it soldiered on in the close-support role with air forces around the world well into the 1950s.

The Republic P-47 Thunderbolt was one of the toughest and most versatile fighters of the war — a machine its pilots trusted utterly, precisely because it so often carried them home from punishment that should have been fatal. From high-altitude escort to devastating ground attack, few aircraft did so many jobs so well.

It lacked the glamour of the Mustang and the grace of the Spitfire, but in sheer survivability and hitting power it had no equal. The big, blunt “Jug” is remembered as the fighter that ruled the low-level battlefield over north-west Europe — heavy, fast and almost indestructible, and one of the great American combat aircraft of the war.

• Roger A. Freeman, Thunderbolt: A Documentary History of the Republic P-47 (Macdonald, 1978).
• William N. Hess, P-47 Thunderbolt at War (Ian Allan).
• Cory Graff, P-47 Thunderbolt at War (Zenith).
• Jerry Scutts, P-47 Thunderbolt Aces of the Eighth Air Force (Osprey).