P-51 Mustang vs P-47 Thunderbolt: Escort Fighter Against Flying Tank

Two answers to the same war

The P-51 Mustang began as a British order. In 1940 North American Aviation told the British Purchasing Commission it could build a better fighter than a license-built Curtiss P-40, and the prototype flew on 26 October 1940.

The P-47 Thunderbolt came from a different tradition. Alexander Kartveli designed it as a successor to the Seversky P-35 and built it around the Pratt & Whitney R-2800 radial engine, with a turbosupercharger for high altitude. The prototype flew on 6 May 1941.

The result was two single-seat fighters of very different shapes. The Mustang was slim and aerodynamic, and the Thunderbolt was huge. The 4th Fighter Group had flown Spitfire Mk Vs, and its pilots joked that a Thunderbolt pilot could defend himself by running around and hiding in the fuselage.

Which was faster?

There is not much in it. The P-51 reaches 383 kt · 441 mph · 709 km/h and the P-47 reaches 376 kt · 433 mph · 696 km/h, according to the figures in the specification panels above.

Climb separates them more clearly. The Mustang climbs at 3,200 ft/min · 16 m/s against 2,780 ft/min · 14 m/s for the Thunderbolt. Early P-47s had mediocre climb, and the Bf 109 and Fw 190 could out-turn and out-climb them at low and medium altitude.

The Thunderbolt did better higher up. Its turbosupercharger gave maximum power at altitude, where the P-47 stayed fast and nimble compared with other aircraft. Pilots used its excellent roll rate and dive to fight on its own terms, rather than turning with German fighters.

Range: where the P-51 won the escort job

The escort mission is where the two split. The USAAF first used P-38s and P-47s to escort bombers on the early part of a raid and handed over to P-51s when they had to turn for home.

The Mustang was so clearly superior to earlier US designs that the Eighth Air Force steadily converted its groups. By the end of 1944, 14 of its 15 fighter groups flew Mustangs.

The panels show why. The Mustang is listed at 1,434 nm · 1,650 mi · 2,660 km with external tanks against 900 nm · 1,040 mi · 1,670 km for the Thunderbolt. The panels list fuel capacity at 270 gal for the Mustang and 370 gal for the Thunderbolt, so the Mustang’s range came from efficiency, not from a bigger tank.

The Thunderbolt was not left behind. As fuel capacity grew through the type’s development, its escort range rose until it could accompany bombers all the way into Germany.

Firepower and bombs

The Thunderbolt carried eight .50 caliber Browning machine guns, four in each wing, with 425 rounds per gun. The Mustang carried six. That is a third more guns on the P-47.

The P-47 also had the heavier ground-attack toolkit. It became the USAAF’s primary fighter-bomber, carrying bombs under the belly and wings, M8 rockets and later 5 in HVARs. Its maximum takeoff weight in the panel is 17,500 lb · 7,950 kg, against 12,100 lb · 5,500 kg for the Mustang.

The Mustang could carry bombs and rockets too, and it did. But the P-47 did the heavy lifting on the ground. Between D-Day and VE Day, its pilots claimed 86,000 railroad cars, 9,000 locomotives, 6,000 armored fighting vehicles and 68,000 trucks.

Surviving damage

This is the Thunderbolt’s best argument. Its air-cooled radial had a high tolerance for damage compared with liquid-cooled engines, and its size meant it could take a lot of punishment and still bring the pilot home.

Luftwaffe ace Heinz Bär said the P-47 “could absorb an astounding amount of lead and had to be handled very carefully.”

The Mustang’s Merlin was liquid-cooled. Strafing hits on the radiator or a coolant line could end a flight quickly, and Mustang losses on strafing missions were much higher than in air-to-air combat.

Combat record

Mustang pilots claimed 4,950 enemy aircraft in the war. Numerical superiority, the Mustang’s flying qualities and pilot proficiency crippled the Luftwaffe fighter force, and by July 1944 the fighter threat to American and British bombers was greatly diminished.

The Thunderbolt ended the war with a 4.6 to 1 aerial kill ratio across more than 746,000 sorties of all types, at the cost of 3,499 P-47s to all causes in combat. Its pilots claimed 20 Me 262 jets and four Arado Ar 234 jet bombers.

The 56th Fighter Group was the only Eighth Air Force unit still flying the P-47 by preference at the end of the war. It claimed 677 and a half aerial victories and 311 ground kills for the loss of 128 aircraft.

Its pilots included Francis “Gabby” Gabreski with 28 victories, Robert S. Johnson with 27 and group commander Hubert Zemke with 17 and three-quarters.

Korea and after

The Mustang, redesignated F-51, was the main US fighter at the start of the Korean War until jets such as the F-86 took over. It then flew as a ground-attack and photo reconnaissance aircraft.

The F-47 Thunderbolt was not deployed to Korea. The Air Force and Air National Guard had more F-51s and used them mainly in the close air support role. Many Mustangs were lost to antiaircraft fire, and some suggested the more durable Thunderbolt should have gone in their place.

The Mustang found work abroad too. The last Mustang shot down in battle fell during Operation Power Pack in the Dominican Republic in 1965, and the last Dominican Mustangs retired in 1984.

So which was better?

The Mustang was the better air-to-air fighter at the altitudes and distances of the bomber war. It went farther, climbed better and gave the Eighth Air Force an escort that could stay with the bombers.

The Thunderbolt was the better aircraft to be shot at in, and the better one to take a heavy load of ordnance onto a target. The two fighters ended up complementing each other, which is why the USAAF flew both.

For more American fighters of the era, see our American fighter planes of WW2 article.