North American P-51D Mustang

The Mustang was among the best and most well-known fighters used by the U.S. Army Air Forces during World War II. Possessing excellent range and maneuverability, the P-51 operated primarily as a long-range escort fighter and also as a ground attack fighter-bomber. The Mustang served in nearly every combat zone during WWII, and later fought in the Korean War.

Origins
In 1940 the British approached North American Aviation to license-build Curtiss P-40 fighters for the Royal Air Force. North American offered to design a better fighter, which flew as the NA-73X in October 1940. Production of the aircraft — named Mustang I by the British — began the following year.

Mustangs for the USAAF
In the summer of 1941, the USAAF received two Mustang Is under the designation XP-51. Although flight tests of the new fighter showed promise, the USAAF did not immediately order the Mustang. After the personal intervention of Gen. Hap Arnold, however, the USAAF retained 55 Mustangs from a British order. Most of these became F-6A photo-reconnaissance aircraft, which equipped the first USAAF Mustang units, the 154th and 111th Observation Squadrons in North Africa in the spring of 1943. 

In March 1942 the USAAF accepted the first production P-51A fighters. Although excellent at lower levels, the P-51A’s Allison engines severely limited performance at high altitude. The USAAF employed P-51As in the China-Burma-India theater, where most combat took place at low altitude. 

In April 1942 the USAAF ordered an attack version equipped with dive brakes and bomb racks, the A-36 Apache. A-36s entered combat in June 1943 and served in North Africa, Italy and India. 

A Winning Combination
In the fall of 1942, Mustangs in the United States and Great Britain were experimentally fitted with British Merlin engines. One in the United States flew a remarkable 441 mph at 29,800 feet — about 100 mph faster than the P-51A at that altitude. Mass production of the Merlin-powered P-51B and P-51C soon followed (nearly identical, North American produced the “B” in Inglewood, Calif., and the “C” in Dallas, Texas). 

In December 1943 the first P-51B/C Mustangs entered combat in Europe with the 354th Fighter Group “Pioneers.” By the time of the first U.S. heavy bomber strike against Berlin in March 1944, the USAAF fielded about 175 P-51B/C Mustangs. Along with P-38 Lightnings, these P-51s provided sorely needed long-range, high-altitude escort for the U.S. bombing campaign against Germany. 

“Bubble-top” Mustang
The P-51D incorporated several improvements, and it became the most numerous variant with nearly 8,000 being built. The most obvious change was a new “bubble-top” canopy that greatly improved the pilot’s vision. The P-51D also received the new K-14 gunsight, an increase from four to six .50-cal machine guns, and a simplified ammunition feed system that considerably reduced gun jams. 

The P-51D arrived in quantity in Europe in the spring of 1944, becoming the USAAF’s primary long range escort fighter. The versatile Mustang also served as a fighter-bomber and reconnaissance aircraft. Few Luftwaffe aircraft could match the P-51D — by the end of the war, Mustangs had destroyed 4,950 enemy aircraft in the air, more than any other USAAF fighter in Europe. 

P-51Ds arrived in the Pacific and CBI theaters by the end of 1944. In the spring of 1945, Iwo Jima-based P-51Ds started flying long-range B-29 escort and low-level fighter-bomber missions against ground targets in Japan. 

Continuing Development
North American eventually developed a considerably lightened Mustang, which became the P-51H. With a remarkable top speed of 487 mph, it was 50 mph faster than the P-51D. Although it was in production before the war ended, the P-51H did not reach frontline units in time to see combat. 

With the last of 555 P-51Hs completed in 1946, the production run of the Mustang ended with over 15,000 of all types built. 

Korean War
Although Mustangs continued in service with the newly-formed U.S. Air Force and many other nations after the war, more advanced jet fighters relegated them to secondary status. Many of the USAF’s Mustangs (redesignated the F-51) were surplused or transferred to the Reserve and the Air National Guard (ANG). 

At the start of the Korean War, however, the Mustang once again proved its usefulness. After the initial invasion, USAF units were forced to fly from bases in Japan, and F-51Ds could hit targets in Korea that short-ranged F-80 jet fighters could not. Mustangs continued flying with USAF, South Korean Air Force (ROKAF), South African Air Force (SAAF) and Royal Australian Air Force (RAAF) fighter-bomber units on close support and interdiction missions in Korea until they were largely replaced by F-86F jet fighter-bombers in 1953. 

Epilogue
F-51s flew in the Reserve and ANG until they were finally phased out in 1957. Obtained from the West Virginia ANG in 1957, the aircraft on display was the last Mustang assigned to a USAF tactical unit. It is painted as the P-51D flown by Col. C.L. Sluder, commander of the 325th Fighter Group in Italy in 1944. The name of this aircraft, Shimmy IV, is derived from the names of his daughter, Sharon, and his wife, Zimmy.