North American P 51 Mustang

Design and development

In April 1940 the British government established a purchasing commission in the United States, headed by Sir Henry Self. Self was given overall responsibility for Royal Air Force (RAF) production and research and development, and also served with Sir Wilfrid Freeman, the Air Member for Development and Production. Self also sat on the British Air Council Sub-committee on Supply (or "Supply Committee") and one of his tasks was to organize the manufacturing and supply of American fighter aircraft for the RAF. At the time, the choice was very limited, as no U.S. aircraft then in production or flying met European standards, with only the Curtiss P-40 Tomahawk coming close. The Curtiss-Wright plant was running at capacity, so P-40s were in short supply.

North American Aviation (NAA) was already supplying its Harvard trainer to the RAF, but was otherwise underutilized. NAA President "Dutch" Kindelberger approached Self to sell a new medium bomber, the B-25 Mitchell. Instead, Self asked if NAA could manufacture the Tomahawk (the British designation for early models of the P-40) under license from Curtiss. Kindelberger said NAA could have a better aircraft with the same engine in the air sooner than establishing a production line for the P-40. The Commission stipulated armament of four .303 in (7.7 mm) machine guns, the Allison V-1710 liquid-cooled engine (as used on the Tomahawk), a unit cost of no more than $40,000, and delivery of the first production aircraft by January 1941. In March 1940, 320 aircraft were ordered by Sir Wilfred Freeman who had become the executive head of the Ministry of Aircraft Production (MAP), and the contract was promulgated on 24 April.

The NA-73X, which was designed by a team led by lead engineer Edgar Schmued, followed the best conventional practice of the era, but included several new features. One was a wing designed using laminar flow airfoils which were developed co-operatively by North American Aviation and the National Advisory Committee for Aeronautics (NACA). These airfoils generated very low drag at high speeds. During the development of the NA-73X, a wind tunnel test of two wings, one using NACA 5-digit airfoils and the other using the new NAA/NACA 45–100 airfoils, was performed in the University of Washington Kirsten Wind Tunnel. The results of this test showed the superiority of the wing designed with the NAA/NACA 45–100 airfoils.

The other feature was a new cooling arrangement (aft positioned, single ducted water and oil radiators assembly) that reduced the cooling drag. It was later discovered that, after lot of development, the cooling assembly could take advantage of the "Meredith Effect", in which heated air exited the radiator with a slight amount of jet thrust. Because NAA lacked a suitable wind tunnel to test this feature, it used the GALCIT 10 ft (3.0 m) wind tunnel at the California Institute of Technology. This led to some controversy over whether the Mustang's cooling system aerodynamics were developed by NAA's engineer Edgar Schmued or by Curtiss, although NAA had purchased the complete set of P-40 and XP-46 wind tunnel data and flight test reports for US$56,000. The NA-73X was also one of the first aircraft to have a fuselage lofted mathematically using conic sections; this resulted in smooth, low drag surfaces. To aid production, the airframe was divided into five main sections—forward, center, rear fuselage and two wing halves — all of which were fitted with wiring and piping before being joined.

The prototype NA-73X was rolled out in September 1940, just 102 days after the order had been placed; it first flew on 26 October 1940, 149 days into the contract, an uncommonly short gestation period even during the war. With test pilot Vance Breese at the controls the prototype handled well and accommodated an impressive fuel load. The aircraft's two-section, semi-monocoque fuselage was constructed entirely of aluminum to save weight. It was armed with four .30 caliber (7.62 mm) M1919 Browning machine guns in the wings and two .50 caliber (12.7 mm) M2 Browning machine guns mounted under the engine and firing through the propeller arc using gun synchronizing gear.

While the United States Army Air Corps (USAAC) could block any sales it considered detrimental to the interests of the US, the NA-73 was considered to be a special case because it had been designed at the behest of the British. In September 1940 a further 300 NA-73s were ordered by the MAP. To ensure uninterrupted delivery Colonel Oliver P. Echols arranged with the Anglo-French Purchasing Commission to deliver the aircraft, and NAA gave two examples (41-038 and 41-039) to the USAAC for evaluation.

United Kingdom operational service

The Mustang was initially developed for the RAF, who were its first users. As the first Mustangs were built to British requirements, these aircraft used factory numbers and were not P-51s; the order comprised 320 NA-73s, followed by 300 NA-83s, all of which were designated North American Mustang Mark I by the RAF. The first RAF Mustangs supplied under Lend-Lease were 93 P-51s, designated Mk Ia, followed by 50 P-51As used as Mustang Mk IIs. Aircraft supplied to Britain under Lend-Lease were required for accounting purposes to be on the USAAC's books before they could be supplied to Britain, and so Lend-Lease aircraft destined for the RAF were first ordered and paid-for on Britain's behalf by the USAAC.

After the arrival of the initial aircraft in the UK in October 1941, the first Mustang Mk Is entered service in January 1942, the first unit being 26 Squadron RAF. Due to poor high-altitude performance, the Mustangs were used by Army Co-operation Command, rather than Fighter Command, and were used for tactical reconnaissance and ground-attack duties. On 10 May 1942, Mustangs first flew over France, near Berck-sur-Mer. On 27 July 1942, 16 RAF Mustangs undertook their first long-range reconnaissance mission over Germany. During the amphibious Dieppe Raid on the French coast (19 August 1942) four British and Canadian Mustang squadrons, including 26 Squadron, saw action covering the assault on the ground. By 1943–1944, British Mustangs were used extensively to seek out V-1 flying bomb sites. The last RAF Mustang Mk I and Mustang Mk II aircraft were struck off charge in 1945.

The RAF also operated 308 P-51Bs and 636 P-51Cs which were known in RAF service as Mustang Mk IIIs; the first units converted to the type in late 1943 and early 1944. Mustang Mk III units were operational until the end of World War II, though many units had already converted to the Mustang Mk IV (P-51D) and Mk IVa (P-51K) (828 in total, comprising 282 Mk IV and 600 Mk IVa). As all except the earliest aircraft were obtained under Lend-Lease, all Mustang aircraft still on RAF charge at the end of the war were either returned to the USAAF "on paper" or retained by the RAF for scrapping. The last RAF Mustangs were retired in 1947.

Pre-war theory

Pre-war doctrine was based on the idea "the bomber will always get through". Despite RAF and Luftwaffe experience with daylight bombing, the USAAC still believed in 1942 that tightly packed formations of bombers would have so much firepower that they could fend off fighters on their own. Fighter escort was low-priority, and when an escort fighter was planned in 1941, a heavy fighter with twin engines, such as the Lockheed P-38 Lightning, was considered to be most appropriate. Another school of thought favored a heavily up-armed "gunship" conversion of a strategic bomber. A single-engined high-speed fighter with the range of a bomber was thought to be an engineering impossibility.

Eighth Air Force bomber operations 1942–1943

The 8th Air Force started operations from Britain in August 1942. At first, because of the limited scale of operations, there was no conclusive evidence American doctrine was failing. In the 26 operations flown to the end of 1942, the loss rate had been under 2%.

In January 1943, at the Casablanca Conference, the Allies formulated the Combined Bomber Offensive (CBO) plan for "round-the-clock" bombing – USAAF daytime operations complementing the RAF nighttime raids on industrial centers. In June 1943, the Combined Chiefs of Staff issued the Pointblank Directive to destroy the Luftwaffe's capacity before the planned invasion of Europe, putting the CBO into full implementation. German daytime fighter efforts were, at that time, focused on the Eastern Front and several other distant locations. Initial efforts by the 8th met limited and unorganized resistance, but with every mission the Luftwaffe moved more aircraft to the west and quickly improved their battle direction. In fall 1943, the 8th Air Force's heavy bombers conducted a series of deep-penetration raids into Germany, beyond the range of escort fighters. The Schweinfurt–Regensburg mission in August lost 60 B-17s of a force of 376, the 14 October attack lost 77 of a force of 291—26% of the attacking force. Losses were so severe that long-range missions were called off for a time until an effective escort could be found.

For the US, the very concept of self-defending bombers was called into question. But instead of abandoning daylight raids and turning to night bombing, as the RAF suggested, they chose other paths; at first it was believed that a bomber with more guns (the Boeing YB-40) would be able to escort the bomber formations, but, when the concept proved to be unsuccessful, thoughts then turned to the Lockheed P-38 Lightning. In early 1943 the USAAF also decided that the Republic P-47 Thunderbolt and P-51B be considered for the role of a smaller escort fighter and, in July a report stated that the P-51B was "the most promising plane" with an endurance of four hours 45 minutes with the standard internal fuel of 184 gallons plus 150 gallons carried externally. In August a P-51B was fitted with an extra internal 85 gallon tank and, although there were problems with longitudinal stability and some compromises in performance with the tank full, it was decided that because the fuel from the fuselage tank would be used during the initial stages of a mission, the fuel tank would be fitted in all Mustangs destined for VIII Fighter Command.

P-51 introduction

The P-51 Mustang was a solution to the need for an effective bomber escort. It used a common, reliable engine and had internal space for a large fuel load. With external fuel tanks, it could accompany the bombers from England to Germany and back.

However, the Allison engine in the P-51A had a single-stage supercharger that caused power to drop off rapidly above 15,000 ft. This made it unsuitable for combat at the altitudes where USAAF bombers planned to fly. Following the RAF's initial disappointing experience with the Mustang I (P-51A) Ronald Harker, a test pilot for Rolls-Royce suggested fitting a Merlin 61, as fitted to the Spitfire Mk IX. The Merlin 61 had a two-speed two-stage intercooled supercharger, designed by Stanley Hooker of Rolls-Royce and this gave an increase in horsepower from the Allison's 1,200 hp (895 kW) to 1,620 hp (1,208 kW) (1,720 hp in War Emergency Power) delivering an increase of top speed from 390 mph (628 kph) to 440 mph (708 kph) as well as raising the service ceiling to almost 42,000 ft (12,800 metres).

Initial flights of what was known to Rolls-Royce as the Mustang Mk X were completed at Rolls-Royce's airfield at Hucknall in October 1942 and after urging from the US assistant air attaché in the UK, Thomas Hitchcock Jr., a similar conversion then took place in the US, leading to production of the P-51B beginning at North American's Inglewood California plant in June 1943 and P-51s started to become available to the 8th and 9th Air Forces in the winter of 1943–1944. During the conversion to the two-stage supercharged Merlin engine, which was slightly heavier than the single-stage Allison and so moved the aircraft's centre-of-gravity forward, North American's engineers took the opportunity to add a large additional fuselage fuel tank behind the pilot, greatly increasing the aircraft's range over that of the earlier P-51A.

By the time the Pointblank offensive resumed in early 1944, matters had changed. Bomber escort defences were initially layered, using the shorter-range P-38s and P-47s to escort the bombers during the initial stages of the raid before handing over to the P-51s when they were forced to turn for home. This provided continuous coverage during the raid. The Mustang was so clearly superior to earlier US designs that the Eighth Air Force began to steadily switch its fighter groups to the Mustang, first swapping arriving P-47 groups to the 9th Air Force in exchange for those that were using P-51s, then gradually converting its Thunderbolt and Lightning groups. By the end of 1944, 14 of its 15 groups flew the Mustang.

The Luftwaffe's twin-engine heavy fighters brought up to deal with the bombers proved to be easy prey for the Mustangs and had to be quickly withdrawn from combat. The Focke-Wulf Fw 190A, already suffering from poor high-altitude performance, was outperformed by the Mustang at the B-17's altitude, and when laden with heavy bomber-hunting weapons as a replacement for the more vulnerable twin-engined Zerstörer heavy fighters, it suffered heavy losses. The Messerschmitt Bf 109 had comparable performance at high altitudes, but its lightweight airframe was even more greatly affected by increases in armament. The Mustang's much lighter armament, tuned for anti-fighter combat, allowed it to overcome these single-engined opponents.

The Luftwaffe adapted to the U.S. fighters by modifying their tactics. Instead of approaching in small ad-hoc formations, they formed up en masse in front of the bomber's line of approach, and then attacked by making a single pass through the formation. Flying in close formation with the bombers, the P-51s had little time to react before the attackers were already flying out of range.

Fighting the Luftwaffe

At the start of 1944, Major General James Doolittle, the new commander of the 8th Air Force, ordered many fighter pilots to stop flying in formation with the bombers and instead attack the Luftwaffe wherever it could be found. The aim was to achieve air supremacy. Mustang groups were sent far ahead of the bombers in a "fighter sweep" in order to intercept attacking German fighters. As a result, the Luftwaffe lost 17% of its fighter pilots in just over a week, and the Allies were able to establish air superiority.

The Luftwaffe' answered with the Gefechtsverband ("battle formation"). This consisted of a Sturmgruppe of heavily armed and armored Fw 190As escorted by two Begleitgruppen of Messerschmitt Bf 109s, whose task was to keep the Mustangs away from the Fw 190As attacking the bombers. This strategy proved to be problematic, as the large German formation took a long time to assemble and was difficult to maneuver. It was often intercepted by the P-51 "fighter sweeps" before it could attack the bombers. However, German attacks against bombers could be effective when they did occur; the bomber-destroyer Fw 190As swept in from astern and often pressed their attacks to within 100 yds (90 m).

While not always able to avoid contact with the escorts, the threat of mass attacks and later the "company front" (eight abreast) assaults by armored Sturmgruppe Fw 190As brought an urgency to attacking the Luftwaffe wherever it could be found, either in the air or on the ground. Beginning in late February 1944, 8th Air Force fighter units began systematic strafing attacks on German airfields with increasing frequency and intensity throughout the spring with the objective of gaining air supremacy over the Normandy battlefield. In general these were conducted by units returning from escort missions but, beginning in March, many groups also were assigned airfield attacks instead of bomber support. The P-51, particularly with the advent of the K-14 Gyro gunsight and the development of "Clobber Colleges" for the training of fighter pilots in fall 1944, was a decisive element in Allied countermeasures against the Jagdverbände.

The numerical superiority of the USAAF fighters, superb flying characteristics of the P-51, and pilot proficiency helped cripple the Luftwaffe's fighter force. As a result, the fighter threat to US, and later British, bombers was greatly diminished by July 1944. The RAF, long proponents of night bombing for protection, were able to re-open daylight bombing in 1944 as a result of the crippling of the Luftwaffe fighter arm. Reichsmarschall Hermann Göring, commander of the German Luftwaffe during the war, was quoted as saying, "When I saw Mustangs over Berlin, I knew the jig was up."

Beyond Pointblank

On 15 April 1944, VIII Fighter Command began "Operation Jackpot", attacks on Luftwaffe fighter airfields. As the efficacy of these missions increased, the number of fighters at the German airbases fell to the point where they were no longer considered worthwhile targets. On 21 May, targets were expanded to include railways, locomotives and rolling stock used by the Germans to transport materiel and troops, in missions dubbed "Chattanooga". The P-51 excelled at this mission, although losses were much higher on strafing missions than in air-to-air combat, partially because the Mustang's liquid-cooled engine (particularly its coolant system) was vulnerable to small arms fire, unlike the air-cooled Double Wasp radials of its Republic P-47 Thunderbolt stablemates based in England, regularly tasked with ground strafing missions.

Given the overwhelming Allied air superiority, the Luftwaffe put its effort into the development of aircraft of such high performance that they could operate with impunity, but which also made bomber attack much more difficult, merely from the flight velocities they achieved. Foremost among these were the Messerschmitt Me 163B point-defense rocket interceptors, which started their operations with JG 400 near the end of July 1944, and the longer-endurance Messerschmitt Me 262A jet fighter, first flying with the Gruppe-strength Kommando Nowotny unit by the end of September 1944. In action, the Me 163 proved to be more dangerous to the Luftwaffe than to the Allies and was never a serious threat. The Me 262A was a serious threat, but attacks on their airfields neutralized them. The pioneering Junkers Jumo 004 axial-flow jet engines of the Me 262As needed careful nursing by their pilots and these aircraft were particularly vulnerable during takeoff and landing. Lt. Chuck Yeager of the 357th Fighter Group was one of the first American pilots to shoot down an Me 262, which he caught during its landing approach. On 7 October 1944, Lt. Urban Drew of the 365th Fighter Group shot down two Me 262s that were taking off, while on the same day Lt. Col. Hubert Zemke, who had transferred to the Mustang equipped 479th Fighter Group, shot down what he thought was a Bf 109, only to have his gun camera film reveal that it may have been an Me 262. On 25 February 1945, Mustangs of the 55th Fighter Group surprised an entire Staffel of Me 262As at takeoff and destroyed six jets.

The Mustang also proved useful against the V-1s launched toward London. P-51B/Cs using 150 octane fuel were fast enough to catch the V-1 and operated in concert with shorter-range aircraft like advanced marks of the Supermarine Spitfire and Hawker Tempest.

By 8 May 1945, the 8th, 9th and 15th Air Force's P-51 groups claimed some 4,950 aircraft shot down (about half of all USAAF claims in the European theater, the most claimed by any Allied fighter in air-to-air combat) and 4,131 destroyed on the ground. Losses were about 2,520 aircraft. The 8th Air Force's 4th Fighter Group was the top-scoring fighter group in Europe, with 1,016 enemy aircraft claimed destroyed. This included 550 claimed in aerial combat and 466 on the ground.

In air combat, the top-scoring P-51 units (both of which exclusively flew Mustangs) were the 357th Fighter Group of the 8th Air Force with 565 air-to-air combat victories and the Ninth Air Force's 354th Fighter Group with 664, which made it one of the top scoring fighter groups. The top Mustang ace was the USAAF's George Preddy, whose final tally stood at 26.83 victories, 23 of which were scored with the P-51, when he was shot down and killed by friendly fire on Christmas Day 1944 during the Battle of the Bulge.

In China and the Pacific Theater

In early 1945, P-51C, D and K variants also joined the Chinese Nationalist Air Force. These Mustangs were provided to the 3rd, 4th and 5th Fighter Groups and used to attack Japanese targets in occupied areas of China. The P-51 became the most capable fighter in China while the Imperial Japanese Army Air Force used the Nakajima Ki-84 Hayate against it.

The P-51 was a relative latecomer to the Pacific Theater. This was due largely to the need for the aircraft in Europe, although the P-38's twin-engine design was considered a safety advantage for long over-water flights. The first P-51s were deployed in the Far East later in 1944, operating in close-support and escort missions, as well as tactical photo reconnaissance. As the war in Europe wound down, the P-51 became more common: eventually, with the capture of Iwo Jima, it was able to be used as a bomber escort during Boeing B-29 Superfortress missions against the Japanese homeland.

The P-51 was often mistaken for the Japanese Kawasaki Ki-61 Hien in both China and Pacific because of its similar appearance.

Pilot observations

Chief Naval Test Pilot and C.O. Captured Enemy Aircraft Flight Capt. Eric Brown, CBE, DSC, AFC, RN, tested the Mustang at RAE Farnborough in March 1944, and noted, "The Mustang was a good fighter and the best escort due to its incredible range, make no mistake about it. It was also the best American dogfighter. But the laminar flow wing fitted to the Mustang could be a little tricky. It could not by any means out-turn a Spitfire. No way. It had a good rate-of-roll, better than the Spitfire, so I would say the plusses to the Spitfire and the Mustang just about equate. If I were in a dogfight, I'd prefer to be flying the Spitfire. The problem was I wouldn't like to be in a dogfight near Berlin, because I could never get home to Britain in a Spitfire!"

The U.S Air Forces, Flight Test Engineering, assessed the Mustang B on 24 April 1944 "The rate of climb is good and the high speed in level flight is exceptionally good at all altitudes, from sea level to 40,000 feet. The airplane is very maneuverable with good controllability at indicated speeds to 400 MPH. The stability about all axes is good and the rate of roll is excellent, however, the radius of turn is fairly large for a fighter. The cockpit layout is excellent, but visibility is poor on the ground and only fair in level flight."

Kurt Bühligen, the third-highest scoring German fighter pilot of World War II's Western Front (with 112 confirmed victories, three against Mustangs), later stated, "We would out-turn the P-51 and the other American fighters, with the Bf 109 or the Fw 190. Their turn rate was about the same. The P-51 was faster than us but our munitions and cannon were better."

Post-World War II

In the aftermath of World War II, the USAAF consolidated much of its wartime combat force and selected the P-51 as a "standard" piston-engine fighter, while other types, such as the P-38 and P-47, were withdrawn or given substantially reduced roles. As the more advanced (P-80 and P-84) jet fighters were introduced, the P-51 was also relegated to secondary duties.

In 1947, the newly formed USAF Strategic Air Command employed Mustangs alongside F-6 Mustangs and F-82 Twin Mustangs, due to their range capabilities. In 1948, the designation P-51 (P for pursuit) was changed to F-51 (F for fighter), and the existing F designator for photographic reconnaissance aircraft was dropped because of a new designation scheme throughout the USAF. Aircraft still in service in the USAF or Air National Guard (ANG) when the system was changed included: F-51B, F-51D, F-51K, RF-51D (formerly F-6D), RF-51K (formerly F-6K), and TRF-51D (two-seat trainer conversions of F-6Ds). They remained in service from 1946 through 1951. By 1950, although Mustangs continued in service with the USAF after the war, the majority of the USAF's Mustangs had become surplus to requirements and placed in storage, while some were transferred to the Air Force Reserve (AFRES) and the Air National Guard (ANG).

From the start of the Korean War, the Mustang once again proved useful. A substantial number of stored or in-service F-51Ds were shipped, via aircraft carriers, to the combat zone and were used by the USAF, the South African Air Force, and the Republic of Korea Air Force (ROKAF). The F-51 was used for ground attack, fitted with rockets and bombs, and photo-reconnaissance, rather than being as interceptors or "pure" fighters. After the first North Korean invasion, USAF units were forced to fly from bases in Japan, and the F-51Ds, with their long range and endurance, could attack targets in Korea that short-ranged F-80 jets could not. Because of the vulnerable liquid cooling system, however, the F-51s sustained heavy losses to ground fire. Due to its lighter structure, and a shortage of spare parts, the newer, faster F-51H was not used in Korea.

Mustangs continued flying with USAF and ROKAF fighter-bomber units on close support and interdiction missions in Korea until 1953, when they were largely replaced as fighter-bombers by USAF F-84s, and by United States Navy (USN) Grumman F9F Panthers. Other air forces and units using the Mustang included the Royal Australian Air Force's (RAAF)'s 77 Squadron, which flew Australian-built Mustangs as part of British Commonwealth Forces Korea. The Mustangs were replaced by Gloster Meteor F8s in 1951. The South African Air Force's (SAAF)'s 2 Squadron used U.S.-built Mustangs as part of the U.S. 18th Fighter Bomber Wing, and had suffered heavy losses by 1953, after which 2 Squadron converted to the F-86 Sabre.

F-51s flew in the Air Force Reserve and Air National Guard throughout the 1950s. The last American USAF Mustang was F-51D-30-NA AF Serial No. 44-74936, which was finally withdrawn from service with the West Virginia Air National Guard's 167th Fighter Interceptor Squadron in January 1957 and retired to what was then called the Air Force Central Museum, although it was briefly reactivated to fly at the 50th anniversary of the Air Force Aerial Firepower Demonstration at the Air Proving Ground, Eglin AFB, Florida, on 6 May 1957. This aircraft, painted as P-51D-15-NA Serial No. 44-15174, is on display at the National Museum of the United States Air Force, Wright-Patterson AFB, in Dayton, Ohio.

The final withdrawal of the Mustang from USAF dumped hundreds of P-51s onto the civilian market. The rights to the Mustang design were purchased from North American by the Cavalier Aircraft Corporation, which attempted to market the surplus Mustang aircraft in the U.S. and overseas. In 1967 and again in 1972, the USAF procured batches of remanufactured Mustangs from Cavalier, most of them destined for air forces in South America and Asia that were participating in the Military Assistance Program (MAP). These aircraft were remanufactured from existing original F-51D airframes but were fitted with new V-1650-7 engines, a new radio fit, tall F-51H-type vertical tails, and a stronger wing that could carry six 0.50 in (13 mm) machine guns and a total of eight underwing hardpoints. Two 1,000 lb (454 kg) bombs and six 5 in (127 mm) rockets could be carried. They all had an original F-51D-type canopy, but carried a second seat for an observer behind the pilot. One additional Mustang was a two-seat dual-control TF-51D (67-14866) with an enlarged canopy and only four wing guns. Although these remanufactured Mustangs were intended for sale to South American and Asian nations through the MAP, they were delivered to the USAF with full USAF markings. They were, however, allocated new serial numbers (67-14862/14866, 67-22579/22582 and 72-1526/1541).

The last U.S. military use of the F-51 was in 1968, when the U. S. Army employed a vintage F-51D (44-72990) as a chase aircraft for the Lockheed YAH-56 Cheyenne armed helicopter project. This aircraft was so successful that the Army ordered two F-51Ds from Cavalier in 1968 for use at Fort Rucker as chase planes. They were assigned the serials 68-15795 and 68-15796. These F-51s had wingtip fuel tanks and were unarmed. Following the end of the Cheyenne program, these two chase aircraft were used for other projects. One of them (68-15795) was fitted with a 106 mm recoilless rifle for evaluation of the weapon's value in attacking fortified ground targets. Cavalier Mustang 68-15796 survives at the Air Force Armament Museum, Eglin AFB, Florida, displayed indoors in World War II markings.

The F-51 was adopted by many foreign air forces and continued to be an effective fighter into the mid-1980s with smaller air arms. The last Mustang ever downed in battle occurred during Operation Power Pack in the Dominican Republic in 1965, with the last aircraft finally being retired by the Dominican Air Force (FAD) in 1984.

Service with other air forces

After World War II, the P-51 Mustang served in the air arms of more than 25 nations. During the war, a Mustang cost about $51,000, while many hundreds were sold postwar for the nominal price of one dollar to signatories of the Inter-American Treaty of Reciprocal Assistance, ratified in Rio de Janeiro in 1947.

The following is a list of some of the countries that used the P-51 Mustang.

 Australia

In November 1944, 3 Squadron RAAF became the first Royal Australian Air Force unit to use Mustangs. At the time of its conversion from the P-40 to the Mustang the squadron was based in Italy with the RAF's First Tactical Air Force.3 Squadron was renumbered 4 Squadron after returning to Australia from Italy and converted to P-51Ds. Several other Australian or Pacific based squadrons converted to either CAC-built Mustangs or to imported P-51Ks from July 1945, having been equipped with P-40s or Boomerangs for wartime service; these units were: 76, 77, 82, 83, 84 and 86 Squadrons. Only 17 Mustangs reached the RAAF's First Tactical Air Force front line squadrons by the time World War II ended in August 1945.76, 77 and 82 Squadrons were formed into 81 Fighter Wing of the British Commonwealth Air Force (BCAIR) which was part of the British Commonwealth Occupation Force (BCOF) stationed in Japan from February 1946. 77 Squadron used its P-51s extensively during the first months of the Korean War, before converting to Gloster Meteor jets.Five reserve units from the Citizen Air Force (CAF) also operated Mustangs. 21 "City of Melbourne" Squadron, based in the state of Victoria; 22 "City of Sydney" Squadron, based in New South Wales; 23 "City of Brisbane" Squadron, based in Queensland; 24 "City of Adelaide" Squadron, based in South Australia; and 25 "City of Perth" Squadron, based in Western Australia; all of these units were equipped with CAC Mustangs, rather than P-51D or Ks. The last Mustangs were retired from these units in 1960 when CAF units adopted a non-flying role.

 Bolivia

Nine Cavalier F-51D (including the two TF-51s) were given to Bolivia, under a program called Peace Condor.

 Canada

Canada had five squadrons equipped with Mustangs during World War II. RCAF 400, 414 and 430 squadrons flew Mustang Mk Is (1942–1944), and 441 and 442 Squadrons flew Mustang Mk IIIs and IVAs in 1945. Postwar, a total of 150 Mustang P-51Ds were purchased and served in two regular (416 "Lynx" and 417 "City of Windsor") and six auxiliary fighter squadrons (402 "City of Winnipeg", 403 "City of Calgary", 420 "City of London", 424 "City of Hamilton", 442 "City of Vancouver" and 443 "City of New Westminster"). The Mustangs were declared obsolete in 1956, but a number of special-duty versions served on into the early 1960s.

 China

The Chinese Nationalist Air Force obtained the P-51 during the late Sino-Japanese War to fight against the Japanese. After the war, Chiang Kai-shek's Nationalist government used the planes against insurgent Communist forces. The Nationalists retreated to Taiwan in 1949. Pilots supporting Chiang brought most of the Mustangs with them, where the aircraft became part of the island's defence arsenal.

 People's Republic of China

The Communist Chinese captured 39 P-51s from the Nationalists while they were retreating to Taiwan.

 Costa Rica

The Costa Rica Air Force flew four P-51Ds from 1955 to 1964.

 Cuba

In November 1958, three US-registered civilian P-51D Mustangs were illegally flown separately from Miami to Cuba, on delivery to the rebel forces of the 26th of July Movement, then headed by Fidel Castro during the Cuban Revolution. One of the Mustangs was damaged during delivery, and none of them were used operationally. After the success of the revolution in January 1959, with other rebel aircraft plus those of the existing Cuban government forces, they were adopted into the Fuerza Aérea Revolucionaria. Due to increasing U.S. restrictions, lack of spares and maintenance experience, they never achieved operational status. At the time of the Bay of Pigs invasion, the two intact Mustangs were already effectively grounded at Campo Columbia and at Santiago. After the failed invasion, they were placed on display with other symbols of "revolutionary struggle", and one remains on display at the Museo del Aire.

 Dominican Republic

The Dominican Republic (FAD) was the largest Latin American air force to employ the P-51D, with six aircraft acquired in 1948, 44 ex-Swedish F-51Ds purchased in 1948 and a further Mustang obtained from an unknown source. It was the last nation to have any Mustangs in service, with some remaining in use as late as 1984. Nine of the final 10 aircraft were sold back to American collectors in 1988.

 El Salvador

The FAS purchased five Cavalier Mustang IIs (and one dual control Cavalier TF-51) that featured wingtip fuel tanks to increase combat range and up-rated Merlin engines. Seven P-51D Mustangs were also in service. They were used during the 1969 Football War against Honduras, the last time the P-51 was used in combat. One of them, FAS-404, was shot down by a F4U-5 flown by Cap. Fernando Soto in the last aerial combat between piston engine fighters in the world.

 France

In late 1944, the first French unit began its transition to reconnaissance Mustangs. In January 1945, the Tactical Reconnaissance Squadron 2/33 of the French Air Force took their F-6Cs and F-6Ds over Germany on photographic mapping missions. The Mustangs remained in service until the early 1950s, when they were replaced by jet fighters.

 Germany

Several P-51s were captured by the Luftwaffe as Beuteflugzeug ("captured aircraft") following crash landings. These aircraft were subsequently repaired and test-flown by the Zirkus Rosarius, or Rosarius Staffel, the official Erprobungskommando of the Luftwaffe High Command, for combat evaluation at Göttingen. The aircraft were repainted with German markings and bright yellow nose and belly for identification. A number of P-51B/P-51Cs – including examples marked with Luftwaffe Geschwaderkennung codes T9+CK, T9+FK, T9+HK and T9+PK (with the "T9" prefix not known to be officially assigned to any existing Luftwaffe formation from their own records, outside of the photos of Zirkus Rosarius-flown aircraft) — with a total of three captured P-51Ds also flown by the unit. Some of these P-51s were found by Allied forces at the end of the war; others crashed during testing. The Mustang is also listed in the appendix to the novel KG 200 as having been flown by the German secret operations unit KG 200, which tested, evaluated and sometimes clandestinely operated captured enemy aircraft during World War II.

 Guatemala

The Fuerza Aérea Guatemalteca (FAG) had 30 P-51D Mustangs in service from 1954 to the early 1970s.

 Haiti

Haiti had four P-51D Mustangs when President Paul Eugène Magloire was in power from 1950-1956, with the last retired in 1973–74 and sold for spares to the Dominican Republic.

 Indonesia

Indonesia acquired some P-51Ds from the departing Netherlands East Indies Air Force in 1949 and 1950. The Mustangs were used against Commonwealth (RAF, RAAF and RNZAF) forces during the Indonesian confrontation in the early 1960s. The last time Mustangs were deployed for military purposes was a shipment of six Cavalier II Mustangs (without tip tanks) delivered to Indonesia in 1972–1973, which were replaced in 1976.

 Israel

A few P-51 Mustangs were illegally bought by Israel in 1948, crated and smuggled into the country as agricultural equipment for use in the War of Independence (1948) and quickly established themselves as the best fighter in the Israeli inventory. Further aircraft were bought from Sweden, and were replaced by jets at the end of the 1950s, but not before the type was used in the Suez Crisis, at the opening of Operation Kadesh. In conjunction with a surprise parachute drop at the Mitla Pass, four P-51s were specially detailed to cut telephone and telegraph wires using their wings in extreme low level runs, which resulted in major interruptions to Egyptian communications.

 Italy

Italy was a postwar operator of P-51Ds; deliveries were slowed by the Korean war, but between September 1947 and January 1951, by MDAP count, 173 examples were delivered. They were used in all the AMI fighter units: 2, 3, 4, 5, 6, and 51 Stormo (Wing), and some in schools and experimental units. Considered a "glamorous" fighter, P-51s were even used as personal aircraft by several Italian commanders. Some restrictions were placed on its use due to unfavorable flying characteristics. Handling had to be done with much care when fuel tanks were fully utilized and several aerobatic maneuvers were forbidden. Overall, the P-51D was highly rated even compared to the other primary post-war fighter in Italian service, the Supermarine Spitfire, partly because these P-51Ds were in very good condition in contrast to all other Allied fighters supplied to Italy. Phasing out of the Mustang began in summer 1958.

 Japan

The P-51C-11-NT Evalina, marked as "278" (former USAAF serial: 44-10816) and flown by 26th FS, 51st FG, was hit by gunfire on 16 January 1945 and belly-landed on Suchon Airfield in China, which was held by the Japanese. The Japanese repaired the aircraft, roughly applied Hinomaru roundels and flew the aircraft to the Fussa evaluation centre (now Yokota Air Base) in Japan.

 Netherlands

The Royal Netherlands East Indies Army Air Force received 40 P-51Ds and flew them during the Indonesian National Revolution particularly the two 'politionele acties': Operatie Product in 1947 and Operatie Kraai in 1949. When the conflict was over, Indonesia received some of the ML-KNIL Mustangs.

 Nicaragua

Fuerza Aerea de Nicaragua (GN) purchased 26 P-51D Mustangs from Sweden in 1954 and later received 30 P-51D Mustangs from the U.S. together with two TF-51 models from MAP after 1954. All aircraft of this type were retired from service by 1964.

 New Zealand

New Zealand ordered 370 P-51 Mustangs to supplement its Vought F4U Corsairs in the Pacific Ocean Areas theatre. Scheduled deliveries were for an initial batch of 30 P-51Ds, followed by 137 more P-51Ds and 203 P-51Ms. The original 30 were being shipped as the war ended in August 1945; these were stored in their packing cases and the order for the additional Mustangs was cancelled. In 1951 the stored Mustangs entered service in 1 (Auckland), 2(Wellington), 3 (Canterbury) and 4 (Otago) squadrons of the Territorial Air Force (TAF). The Mustangs remained in service until they were prematurely retired in August 1955 following a series of problems with undercarriage and coolant system corrosion problems. Four Mustangs served on as target tugs until the TAF was disbanded in 1957. RNZAF pilots in the Royal Air Force also flew the P-51, and at least one New Zealand pilot scored victories over Europe while on loan to a USAAF P-51 squadron.

 Philippines

The Philippines acquired 103 P-51D Mustangs after World War II. These became the backbone of the postwar Philippine Army Air Corps and Philippine Air Force and were used extensively during the Huk campaign, fighting against Communist insurgents.Mustangs were also the first aircraft of the Philippine air demonstration squadron, which was formed in 1953 and given the name "The Blue Diamonds" the following year. The Mustangs were replaced by 56 F-86 Sabres in the late 1950s, but some were still in service for COIN roles up to the early 1980s.

 Poland

During World War II, five Polish Air Force in Great Britain squadrons used Mustangs. The first Polish unit equipped (7 June 1942) with Mustang Mk Is was "B" Flight of 309 "Ziemi Czerwieńskiej" Squadron (an Army Co-Operation Command unit), followed by "A" Flight in March 1943. Subsequently, 309 Squadron was redesignated a fighter/reconnaissance unit and became part of Fighter Command. On 13 March 1944, 316 "Warszawski" Squadron received their first Mustang Mk IIIs; rearming of the unit was completed by the end of April. By 26 March 1943, 306 "Toruński" Sqn and 315 "Dębliński" Sqn received Mustangs Mk IIIs (the whole operation took 12 days). On 20 October 1944, Mustang Mk Is in No. 309 Squadron were replaced by Mk IIIs. On 11 December 1944, the unit was again renamed, becoming 309 Dywizjon Myśliwski "Ziemi Czerwieńskiej" or 309 "Land of Czerwien" Polish Fighter Squadron. In 1945, 303 "Kościuszko" Sqn received 20 Mustangs Mk IV/Mk IVA replacements. Postwar, between 6 December 1946 and 6 January 1947, all five Polish squadrons equipped with Mustangs were disbanded. Poland returned approximately 80 Mustangs Mk IIIs and 20 Mustangs Mk IV/IVAs to the RAF, which transferred them to the U.S. government.

 Somalia

The Somalian Air Force operated eight P-51Ds in post-World War II service.

South Africa

No.5 Squadron South African Air Force operated a number of Mustang Mk IIIs (P-51B/C) and Mk IVs (P-51D/K) in Italy during World War II, beginning in September 1944 when the squadron converted to the Mustang Mk III from Kittyhawks. The Mk IV and Mk IVA came into SA service in March 1945. These aircraft were generally camouflaged in the British style, having been drawn from RAF stocks; all carried RAF serial numbers and were struck off charge and scrapped in October 1945. In 1950, 2 Squadron SAAF was supplied with F-51D Mustangs by the United States for Korean War service. The type performed well in South African hands before being replaced by the F-86 Sabre in 1952 and 1953.

 South Korea

Within a month of the outbreak of the Korean War, 10 F-51D Mustangs were provided to the badly depleted Republic of Korea Air Force as a part of the Bout One Project. They were flown by both South Korean airmen, several of whom were veterans of the Imperial Japanese Army and Navy air services during World War II, as well as by U.S. advisers led by Major Dean Hess. Later, more were provided both from U.S. and from South African stocks, as the latter were converting to F-86 Sabres. They formed the backbone of the South Korean Air Force until they were replaced by Sabres.It also served with the ROKAF Black Eagles aerobatic team, until retired 1954.

 Sweden

Sweden's Flygvapnet first recuperated four of the P-51s (two P-51Bs and two early P-51Ds) that had been diverted to Sweden during missions over Europe. In February 1945, Sweden purchased 50 P-51Ds designated J 26, which were delivered by American pilots in April and assigned to the F 16 wing at Uppsala as interceptors. In early 1946, the F 4 wing at Östersund was equipped with a second batch of 90 P-51Ds. A final batch of 21 Mustangs was purchased in 1948. In all, 161 J 26s served in the Swedish Air Force during the late 1940s. About 12 were modified for photo reconnaissance and re-designated S 26. Some of these aircraft participated in the secret Swedish mapping of new Soviet military installations at the Baltic coast in 1946–47 (Operation Falun), an endeavour that entailed many intentional violations of Soviet airspace. However, the Mustang could outdive any Soviet fighter of that era, so no S 26s were lost in these missions. The J 26s were replaced by De Havilland Vampires around 1950. The S 26s were replaced by S 29Cs in the early 1950s.

Switzerland

The Swiss Air Force operated a few USAAF P-51s that had been impounded by Swiss authorities during World War II after the pilots were forced to land in neutral Switzerland. After the war, Switzerland also bought 130 P-51s for $4,000 each. They served until 1958.

USSR

The Soviet Union received at least 10 early-model ex-RAF Mustang Mk Is and tested but found them to "under-perform" compared to contemporary USSR fighters, relegating them to training units. Later Lend-Lease deliveries of the P-51B/C and D series, along with other Mustangs abandoned in Russia after the famous "shuttle missions", were repaired and used by the Soviet Air Force but not in front-line service.

Uruguay

The Uruguayan Air Force (FAU) used 25 P-51D Mustangs from 1950 to 1960; some were subsequently sold to Bolivia.

P-51s and civil aviation

Many P-51s were sold as surplus after the war, often for as little as $1,500. Some were sold to former wartime fliers or other aficionados for personal use, while others were modified for air racing. One of the most significant Mustangs involved in air racing was a surplus P-51C-10-NT (44-10947) purchased by film stunt pilot Paul Mantz. The aircraft was modified by creating a "wet wing", sealing the wing to create a giant fuel tank in each wing, which eliminated the need for fuel stops or drag-inducing drop tanks. This Mustang, named "Blaze of Noon" after the film Blaze of Noon, came in first in the 1946 and 1947 Bendix Air Races, second in the 1948 Bendix, and third in the 1949 Bendix. He also set a U.S. coast-to-coast record in 1947. The Mantz Mustang was sold to Charles F. Blair Jr (future husband of Maureen O'Hara) and renamed Excalibur III. Blair used it to set a New York-to-London (c. 3,460 mi/5,568 km) record in 1951: 7h 48min from takeoff at Idlewild to overhead London Airport. Later that same year, he flew from Norway to Fairbanks, Alaska, via the North Pole (c. 3,130 mi/5,037 km), proving that navigation via sun sights was possible over the magnetic north pole region. For this feat, he was awarded the Harmon Trophy, and the Air Force was forced to change its thoughts on a possible Soviet air strike from the north. This Mustang now resides in the National Air and Space Museum at the Steven F. Udvar-Hazy Center.

The most prominent firm to convert Mustangs to civilian use was Trans-Florida Aviation, later renamed Cavalier Aircraft Corporation, which produced the Cavalier Mustang. Modifications included a taller tailfin and wingtip tanks. A number of conversions included a Cavalier Mustang specialty: a "tight" second seat added in the space formerly occupied by the military radio and fuselage fuel tank.

In 1958, 78 surviving RCAF Mustangs were retired from service's inventory and were ferried by Lynn Garrison an RCAF pilot, from their varied storage locations to Canastota, New York, where the American buyers were based. In effect, Garrison flew each of the surviving aircraft at least once. These aircraft make up a large percentage of the aircraft presently flying worldwide.

In the late 1960s and early 1970s, when the United States Department of Defense wished to supply aircraft to South American countries and later Indonesia for close air support and counter insurgency, it turned to Cavalier to return some of their civilian conversions back to updated military specifications.

In the 21st century, a P-51 can command a price of more than $1 million, even for only partially restored aircraft. There were 204 privately owned P-51s in the U.S. on the FAA registry in 2011, most of which are still flying, often associated with organizations such as the Commemorative Air Force (formerly the Confederate Air Force).

In May 2013, Doug Matthews set an altitude record of 42,568 ft (12,975 m) in a P 51 named "The Rebel," for piston powered aircraft weighing 3,000 to 6,000 kg (6,600 to 13,200 lb). Mathews departed from a grass runway at Florida's Indiantown airport and flew "The Rebel" over Lake Okeechobee. He set world records for time to reach altitudes of 9,000 m (30,000 ft), 18 minutes, and 12,000 m (39,000 ft), 31 minutes. He achieved a new height record of 40,100 ft (12,200 m) in level flight and a 42,500 ft (13,000 m) maximum altitude. The previous record of 36,902 ft (11,248 m) had stood since 1954.

Incidents

On June 9, 1973 William Penn Patrick (43) a certified pilot, and his passenger, Christian Hagert, died when Patrick's privately owned P-51 Mustang crashed in Lakeport, California.

On September 16, 2011 The Galloping Ghost, a modified P-51 piloted by Jimmy Leeward of Ocala, Florida, crashed during an air race in Reno, Nevada. Leeward and at least nine people on the ground were killed when the racer suddenly crashed near the edge of the grandstand.

On October 23, 2013, "Galveston Gal," P-51D no. 44-73458 N4151D, piloted by 51-year-old pilot Keith Hibbett of Denton accompanied by his 66-year-old passenger John Stephen Busby, who was visiting from the United Kingdom, were killed when the aircraft crashed in about four feet of water off the coast of Galveston, Texas. Busby was celebrating his 41st wedding anniversary.

On July 4, 2014, John Early and Michael Schlarb were killed when Early's P-51 crashed shortly after takeoff near Durango, Colorado.

Variants

Over twenty variants of the P-51 Mustang were produced from 1940, to after the War.

Production

Except for the small numbers assembled or produced in Australia, all Mustangs were built by North American initially at Inglewood, California but then additionally in Dallas, Texas.

Specifications (P-51D Mustang)

Data from Erection and Maintenance Manual for P-51D and P-51K. P-51 Tactical Planning Characteristics & Performance Chart, The Great Book of Fighters, and Quest for Performance

General characteristics

Crew: 1

Length: 32 ft 3 in (9.83 m)

Wingspan: 37 ft 0 in (11.28 m)

Height: 13 ft 4½ in (4.08 m:tail wheel on ground, vertical propeller blade.)

Wing area: 235 sq ft (21.83 m²)

Airfoil: NAA/NACA 45-100 / NAA/NACA 45-100

Empty weight: 7,635 lb (3,465 kg)

Loaded weight: 9,200 lb (4,175 kg)

Max. takeoff weight: 12,100 lb (5,490 kg)

Maximum fuel capacity: 419 US gal (349 imp gal; 1,590 l)

Zero-lift drag coefficient: 0.0163

Drag area: 3.80 sqft (0.35 m²)

Aspect ratio: 5.83

Powerplant: 1 × Packard V-1650-7 liquid-cooled V-12, with a 2 stage intercooled supercharger, 1,490 hp (1,111 kW) at 3,000 rpm; 1,720 hp (1,282 kW) at WEP

Propellers: constant-speed, variable-pitch Hamilton Standard, propeller

Propeller diameter: 11 ft 2 in (3.40 m)

Performance

Maximum speed: ~440 mph (383 kn, 708 km/h) at 25,000 ft (7,600 m)

Cruise speed: 362 mph (315 kn, 580 km/h)

Stall speed: 100 mph (87 kn, 160 km/h)

Range: 1,650 mi (1,434 nmi, 2,755 km) with external tanks

Service ceiling: 41,900 ft (12,800 m)

Rate of climb: 3,200 ft/min (16.3 m/s)

Wing loading: 39 lb/sqft (192 kg/m²)

Power/mass: 0.18 hp/lb (300 W/kg)

Lift-to-drag ratio: 14.6

Recommended Mach limit 0.8

Armament

Guns: 6 × 0.50 caliber (12.7mm) AN/M2 Browning machine guns with 1,840 total rounds (380 rounds for each on the inboard pair, and 270 rounds for each of the outer two pair)

Rockets: 6 or 10 × 5.0 in (127 mm) T64 H.V.A.R rockets (P-51D-25, P-51K-10 on)

Bombs: 1,000 lb (453 kg) total on two wing hardpoints

Each hardpoint: 1 x 100 lb (45 kg) bomb, 1 x 250 lb (113 kg) bomb or 1 x 500 lb (226 kg) bomb)

Notable appearances in media

The Tuskegee Airmen (1995), the story of how a group of African-American pilots overcame racist opposition to become one of the finest U.S. fighter groups in World War II, flying P-51s, although the 99th Squadron would have used P-40s and P-39s during their North African stint.

Red Tail Reborn (2007), the story behind the restoration of a flying memorial aircraft.

Red Tails (2012) is a George Lucas produced film about the Tuskegee Airmen of the 332nd Fighter Group, featuring P-51 Mustangs in their role as escort fighters.

Scale replicas

As indicative of the iconic nature of the P-51, manufacturers within the hobby industry have created scale plastic model kits of the P-51 Mustang, with varying degrees of detail and skill levels. The aircraft have also been the subject of numerous scale flying replicas. Aside from the popular R/C-controlled aircraft, several kitplane manufacturers offer ½, ⅔, and ¾-scale replicas capable of comfortably seating one (or even two) and offering high performance combined with more forgiving flight characteristics. Such aircraft include the Titan T-51 Mustang, W.A.R. P-51 Mustang, Linn Mini Mustang, Jurca Gnatsum, Thunder Mustang, Stewart S-51D Mustang and the Loehle 5151 Mustang.