The
Republic P-47 Thunderbolt is one of the largest and heaviest
fighter aircraft in history to be powered by a single 4-stroke internal combustion
engine. It was built from 1941–1945. It was heavily armed with eight
.50-caliber machine guns, four per wing. When fully loaded, the P-47 weighed up to eight tons, and in the fighter-bomber ground-attack roles could carry five-inch rockets or a significant bomb load of 2,500 pounds; it could carry more than half the payload of the
B-17 bomber on long-range missions (although the B-17 had a far greater range). The P-47 was designed around the powerful
Pratt & Whitney R-2800 Double Wasp engine—the same engine used by two very successful U.S. Navy fighters, the
Grumman F6F Hellcat and
Vought F4U Corsair, the latter of which was the first to fly with Double Wasp power in late May 1940—and was to be very effective as a short-to-medium range escort fighter in high-altitude
air-to-air combat. When deployed as a fighter-bomber with its usual "double quartet" of heavy-caliber
M2 Browning machine guns, it proved especially adept at
ground attack in both the
World War II European and
Pacific Theaters.