The North American Aviation P-51 Mustang is an American long-range, single-seat fighter and fighter-bomber used during World War II and the Korean War, among other conflicts. The Mustang was designed in April 1940 by a team headed by James H. Kindelberger of North American Aviation (NAA) in response to a requirement of the British Purchasing Commission. The Purchasing Commission approached North American Aviation to build Curtiss P-40 fighters under license for the Royal Air Force (RAF). Rather than build an old design from another company, North American Aviation proposed the design and production of a more modern fighter. The prototype NA-73X airframe was rolled out on 9 September 1940, 102 days after the contract was signed, and first flew on 26 October.
|P-51D of 375th Fighter Squadron, with underwing drop tanks|
|National origin||United States|
|Manufacturer||North American Aviation|
|First flight||26 October 1940|
|Introduction||January 1942 (RAF)|
|Status||Retired from military service 1984 (Dominican Air Force). Still used in air racing by civilians and as warbirds.|
|Primary users||United States Army Air Forces|
Royal Air Force
Royal New Zealand Air Force
Royal Canadian Air Force
|Number built||More than 15,000|
|Variants||North American A-36|
Rolls-Royce Mustang Mk.X
|Developed into||North American F-82 Twin Mustang|
Piper PA-48 Enforcer
The Mustang was designed to use the Allison V-1710 engine, which had limited high-altitude performance in its earlier variants. The aircraft was first flown operationally by the RAF as a tactical-reconnaissance aircraft and fighter-bomber (Mustang Mk I). Replacing the Allison with a Rolls-Royce Merlin resulted in the P-51B/C (Mustang Mk III) model, and transformed the aircraft's performance at altitudes above 15,000 ft (4,600 m) (without sacrificing range), allowing it to compete with the Luftwaffe's fighters. The definitive version, the P-51D, was powered by the Packard V-1650-7, a license-built version of the two-speed, two-stage-supercharged Merlin 66, and was armed with six .50 caliber (12.7 mm) AN/M2 Browning machine guns.
From late 1943, P-51Bs and P-51Cs (supplemented by P-51Ds from mid-1944) were used by the USAAF's Eighth Air Force to escort bombers in raids over Germany, while the RAF's Second Tactical Air Force and the USAAF's Ninth Air Force used the Merlin-powered Mustangs as fighter-bombers, roles in which the Mustang helped ensure Allied air superiority in 1944. The P-51 was also used by Allied air forces in the North African, Mediterranean, Italian, and Pacific theaters. During World War II, Mustang pilots claimed to have destroyed 4,950 enemy aircraft.[nb 1]
At the start of the Korean War, the Mustang, by then redesignated F-51, was the main fighter of the United States until jet fighters, including North American's F-86, took over this role; the Mustang then became a specialized fighter-bomber. Despite the advent of jet fighters, the Mustang remained in service with some air forces until the early 1980s. After the Korean War, Mustangs became popular civilian warbirds and air racing aircraft.
In 1938, the British government established a purchasing commission in the United States, headed by Sir Henry Self. Self was given overall responsibility for RAF production, 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 T-6 Texan (known in British service as the "Harvard") trainer to the RAF, but was otherwise underused. NAA President "Dutch" Kindelberger approached Self to sell a new medium bomber, the North American B-25 Mitchell. Instead, Self asked if NAA could manufacture P-40s under license from Curtiss. Kindelberger said NAA could have a better aircraft with the same Allison V-1710 engine in the air sooner than establishing a production line for the P-40.
John Attwood of North American spent much time from January to April 1940 at the British Purchasing Commission's offices in New York discussing the British specifications of the proposed aircraft with British engineers. The discussions consisted of free-hand conceptual drawings of an aircraft with the British officials. Sir Henry Self was concerned that North American had not ever designed a fighter, insisting they obtain the drawings and study the Curtiss XP-46 experimental aircraft and the wind tunnel test results for the P-40, before presenting them with detailed design drawings based on the agreed concept. North American purchased the drawings and data from Curtiss for £56,000,[verification needed] confirming the purchase with the Purchasing Commission. The Purchasing Commission approved the resulting detailed design drawings, signing the commencement of the Mustang project on 4 May 1940, firmly ordering 320 on 29 May 1940. Prior to this, North American only had a draft letter for an order of 320 aircraft. Curtiss engineers accused North American of plagiarism.
The British Purchasing Commission stipulated armament of four .303 in (7.7 mm) machine guns (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 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, designed for ease of mass manufacturing. The design included several new features.[nb 2] 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 low drag at high speeds. During the development of the NA-73X, a wind tunnel test of two wings, one using NACA five-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.[nb 3]
The other feature was a new cooling arrangement positioned aft (single ducted water and oil radiators assembly) that reduced the fuselage drag and effects on the wing. Later, after much development, they discovered that 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 3.0 m (10 ft) 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, as NAA had purchased the complete set of P-40 and XP-46 wind tunnel data and flight test reports. 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 development 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 three-section, semi-monocoque fuselage was constructed entirely of aluminum to save weight. It was armed with four .30 caliber (7.62 mm) AN/M2 Browning machine guns in the wings and two .50 caliber (12.7 mm) AN/M2 Browning machine guns mounted under the engine and firing through the propeller arc using gun-synchronizing gear.[nb 4]
While the 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.[nb 5]
The Allison engine in the Mustang I had a single-stage supercharger that caused power to drop off rapidly above 15,000 feet (4,600 m). This made it unsuitable for use at the altitudes where combat was taking place in Europe. Allison’s attempts at developing a high-altitude engine were underfunded, but produced the V-1710-45, which featured a variable-speed auxiliary supercharger, and developed 1,150 horsepower (860 kW) at 22,400 feet (6,800 m). In November 1941, NAA studied the possibility of using it, but fitting its excessive length in the Mustang would require extensive airframe modifications and cause long production delays. In May 1942, following positive reports from the RAF on the Mustang I's performance below 15,000 ft, 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. Both the Merlin 61 and V-1710-39 were capable of about 1,570 horsepower (1,170 kW) war emergency power at relatively low altitude, but the Merlin developed 1,390 horsepower (1,040 kW) at 23,500 feet (7,200 m) versus the Allison's 1,150 horsepower (860 kW) at 11,800 feet (3,600 m), delivering an increase in top speed from 390 mph (340 kn; 630 km/h) at ~15,000 feet (4,600 m) to an estimated 440 mph (380 kn; 710 km/h) at 28,100 feet (8,600 m). 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.
At the same time, the possibility of combining the P-51 airframe with the US license-built Packard version of the Merlin engine was being explored on the other side of the Atlantic. In July 1942, a contract was let for two prototypes, briefly designated XP-78, but soon to become the XP-51B. Based on the Packard V-1650-3 duplicating the Merlin 61's performance, NAA estimated for the XP-78 a top speed of 445 mph (387 kn; 716 km/h) at 28,000 feet (8,500 m), and a service ceiling of 42,000 feet (13,000 m). The first flight of the XP-51B took place in November 1942, but the USAAF was so interested in the possibility that an initial contract for 400 aircraft was placed three months beforehand in August. The conversion led 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. Conversion to the two-stage supercharged Merlin 61, over 350 lb (160 kg) heavier than the single-stage Allison, driving a four-bladed Hamilton Standard propeller, required moving the wing slightly forward to correct the aircraft's center of gravity. After the USAAF, in July 1943, directed fighter aircraft manufacturers to maximize internal fuel capacity, NAA calculated the P-51B's center of gravity to be forward enough to include an additional 85 US gal (320 l; 71 imp gal) fuel tank in the fuselage behind the pilot, greatly increasing the aircraft's range over that of the earlier P-51A. NAA incorporated the tank in the production of the P-51B-10, and supplied kits to retrofit it to all existing P-51Bs.
The Mustang was initially developed for the RAF, which was its first user. 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. However, the British Aircraft Purchasing Commission signed its first contract for the North American NA-73 on 24 April 1940, before Lend-Lease was in effect. Thus, the initial order for the P-51 Mustang (as it was later known) was placed by the British under the "Cash and Carry" program, as required by the US Neutrality Acts of the 1930s.
After the arrival of the initial aircraft in the UK in October 1941, the first squadron of Mustang Mk Is entered service in January 1942, the first being No. 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.
Army Co-operation Command used the Mustang’s superior speed and long range to conduct low-altitude “Rhubarb” raids over continental Europe, sometimes penetrating German airspace. The V-1710 engine ran smoothly at 1,100 rpm, versus 1,600 for the Merlin, enabling long flights over water at 50 ft (15 m) altitude before approaching the enemy coastline. Over land, these flights followed a zig-zag course, turning every six minutes to foil enemy attempts at plotting an interception. During the first 18 months of Rhubarb raids, RAF Mustang Mk.Is and Mk.Ias destroyed or heavily damaged 200 locomotives, over 200 canal barges, and an unknown number of enemy aircraft parked on the ground, for a loss of eight Mustangs. At sea level, the Mustangs were able to outrun all enemy aircraft encountered. The RAF gained a significant performance enhancement at low altitude by removing or resetting the engine’s manifold pressure regulator to allow over-boosting, raising output as high as 1,780 horsepower at 70" Hg. In December 1942, Allison approved only 1,570 horsepower at 60" Hg manifold pressure for the V-1710-39.
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 from service in 1947.
Prewar doctrine was based on the idea "the bomber will always get through". Despite RAF and Luftwaffe experience with daylight bombing, the USAAF still incorrectly 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 a low priority, but when the concept was discussed in 1941, the Lockheed P-38 Lightning was considered to be most appropriate as it had the speed and range. 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.
The 8th Air Force started operations from Britain in August 1942. At first, because of the limited scale of operations, no conclusive evidence showed 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. 
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, bombers converted to gunships (the Boeing YB-40) was believed to 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 4 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 but problems with longitudinal stability occurred so some compromises in performance with the tank full were made. Since 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.
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 larger-than-average fuel load. With external fuel tanks, it could accompany the bombers from England to Germany and back.
By the time the Pointblank offensive resumed in early 1944, matters had changed. Bomber escort defenses 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 8th 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-engined Messerschmitt Bf 110 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 antifighter combat, allowed it to overcome these single-engined opponents.
At the start of 1944, Major General James Doolittle, the new commander of the 8th Air Force, released most fighters from the requirement of flying in close formation with the bombers, allowing them free rein to 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" to intercept German fighters. Bomber crews complained but by June supremacy was achieved.
The Luftwaffe answered with the Gefechtsverband ("battle formation"). This consisted of a Sturmgruppe of heavily armed and armored Fw 190 As escorted by two Begleitgruppen of Messerschmitt Bf 109s, whose task was to keep the Mustangs away from the Fw 190 as they attacked 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 90 m (100 yd).
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 the US, and later British, bombers was greatly diminished by July 1944. The RAF, long proponents of night bombing for protection, were able to reopen 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."
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 other 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 liquid coolant system) was vulnerable to small-arms fire, unlike the air-cooled R-2800 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 L. Drew of the 361st 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 such as advanced marks of the Supermarine Spitfire and Hawker Tempest.
By 8 May 1945, the 8th, 9th, and 15th Air Force's P-51 groups [nb 6] 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 9th 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 (a number that includes shared one half- and one third victory credits), 23 of which were scored with the P-51. Preddy was shot down and killed by friendly fire on Christmas Day 1944 during the Battle of the Bulge.
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, due largely to the need for the aircraft in Europe, although the P-38's twin-engined 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. With the capture of Iwo Jima, USAAF P-51 Mustang fighters of the VII Fighter Command were stationed on that island starting in March 1945, being initially tasked with escorting Boeing B-29 Superfortress missions against the Japanese homeland.
The command's last major raid of May was a daylight incendiary attack on Yokohama on 29 May conducted by 517 B-29s escorted by 101 P-51s. This force was intercepted by 150 A6M Zero fighters, sparking an intense air battle in which five B-29s were shot down and another 175 damaged. In return, the P-51 pilots claimed 26 "kills" and 23 "probables" for the loss of three fighters. The 454 B-29s that reached Yokohama struck the city's main business district and destroyed 6.9 square miles (18 km2) of buildings; over 1000 Japanese were killed. Overall, the attacks in May destroyed 94 square miles (240 km2) of buildings, which was equivalent to one-seventh of Japan's total urban area. The Minister of Home Affairs, Iwao Yamazaki, concluded after these raids that Japan's civil defense arrangements were "considered to be futile". On the first day of June, 521 B-29s escorted by 148 P-51s were dispatched in a daylight raid against Osaka. While en route to the city, the Mustangs flew through thick clouds, and 27 of the fighters were destroyed in collisions. Nevertheless, 458 heavy bombers and 27 P-51s reached the city, and the bombardment killed 3,960 Japanese and destroyed 3.15 square miles (8.2 km2) of buildings. On 5 June, 473 B-29s struck Kobe by day and destroyed 4.35 square miles (11.3 km2) of buildings for the loss of 11 bombers. A force of 409 B-29s attacked Osaka again on 7 June; during this attack, 2.21 square miles (5.7 km2) of buildings were burnt out and the Americans did not suffer any losses. Osaka was bombed for the fourth time that month, on 15 June, when 444 B-29s destroyed 1.9 square miles (4.9 km2) of the city and another 0.59 square miles (1.5 km2) of nearby Amagasaki; 300,000 houses were destroyed in Osaka. This attack marked the end of the first phase of XXI Bomber Command's attack on Japan's cities. During May and June, the bombers had destroyed much of the country's six largest cities, killing between 112,000 and 126,762 people and rendering millions homeless. The widespread destruction and high number of casualties from these raids caused many Japanese to realize that their country's military was no longer able to defend the home islands. American losses were low compared to Japanese casualties; 136 B-29s were downed during the campaign. In Tokyo, Osaka, Nagoya, Yokohama, Kobe, and Kawasaki, "over 126,762 people were killed ... and a million and a half dwellings and over 105 square miles (270 km2) of urban space were destroyed." In Tokyo, Osaka and Nagoya, "the areas leveled (almost 100 square miles (260 km2)) exceeded the areas destroyed in all German cities by both the American and British air forces (about 79 square miles (200 km2))."
P-51s also conducted a series of independent ground-attack missions against targets in the home islands. The first of these operations took place on 16 April, when 57 P-51s strafed Kanoya Air Field in Kyushu. In operations conducted between 26 April and 22 June, the American fighter pilots claimed the destruction of 64 Japanese aircraft and damage to another 180 on the ground, as well as a further 10 shot down in flight; these claims were lower than the American planners had expected, however, and the raids were considered unsuccessful. USAAF losses were 11 P-51s to enemy action and seven to other causes.
Due to the lack of Japanese air opposition to the American bomber raids, VII Fighter Command was solely tasked with ground-attack missions from July. These raids were frequently made against airfields to destroy aircraft being held in reserve to attack the expected Allied invasion fleet. While the P-51 pilots only occasionally encountered Japanese fighters in the air, the airfields were protected by antiaircraft batteries and barrage balloons. By the end of the war, VII Fighter Command had conducted 51 ground-attack raids, of which 41 were considered successful. The fighter pilots claimed to have destroyed or damaged 1,062 aircraft and 254 ships, along with large numbers of buildings and railway rolling stock. American losses were 91 pilots killed and 157 Mustangs destroyed.
Two P-51 pilots received the Medal of Honor during World War II:
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 thus:
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 up to 400 MPH [sic]. 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."
German fighter ace Heinz Bär said that the P-51:
was perhaps the most difficult of all Allied aircraft to meet in combat. It was fast, maneuverable, hard to see, and difficult to identify because it resembled the Me 109.
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-engined 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 and the 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. On August 5, 1950, Major Louis J. Sebille of the 67th Fighter-Bomber Squadron attacked a North Korean armored column advancing on United Nations military units during the Battle of Pusan Perimeter. Though his aircraft was heavily damaged and he was wounded during the first pass on the column, he turned his F-51 around and deliberately crashed into the convoy at the cost of his life, and was posthumously awarded the Medal of Honor.
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 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 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 ANG 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.[page needed]
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 fitted with new V-1650-7 engines, a new radio, tall F-51H-type vertical tails, and a stronger wing that could carry six 13 mm (0.50 in) machine guns and a total of eight underwing hardpoints. Two 1,000-pound (450 kg) bombs and six 130 mm (5 in) 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).[page needed]
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 in 1984.
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.
These countries used the P-51 Mustang:
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 serial number 44-10947, a surplus P-51C-10-NT purchased by film stunt pilot Paul Mantz. He modified the wings, sealing them to create a giant fuel tank in each one; these "wet wings" reduced the need for fuel stops or drag-inducing drop tanks. Named Blaze of Noon after the film Blaze of Noon, the aircraft won the 1946 and 1947 Bendix Air Races, took second in the 1948 Bendix, and placed third in the 1949 Bendix. Mantz also set a U.S. coast-to-coast record in 1947. He sold the Mustang to Charles F. Blair Jr (future husband of Maureen O'Hara), who renamed it Excalibur III and used it to set a New York-to-London (about 3,460 miles or 5,570 kilometres) record in 1951: 7 hr 48 min from takeoff at Idlewild to overhead London Airport. Later that year, Blair flew from Norway to Fairbanks, Alaska, via the North Pole (about 3,130 miles or 5,040 kilometres), 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 sits in the National Air and Space Museum's Steven F. Udvar-Hazy Center.
In 1958, the RCAF retired its 78 remaining Mustangs. RCAF pilot Lynn Garrison ferried them from their various storage locations to Canastota, New York, where the American buyers were based. Garrison flew each of the surviving aircraft at least once. These aircraft make up a large percentage of the aircraft presently flying worldwide.
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 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 counterinsurgency, it paid 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 12,975 m (42,568 ft) in a P-51 named The Rebel for piston-powered aircraft weighing 3,000 to 6,000 kg (6,600 to 13,200 lb). Flying from a grass runway at Florida's Indiantown airport and over Lake Okeechobee, Matthews 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 set a level-flight altitude record of 12,200 m (40,100 ft) in level flight and an absolute altitude record of 13,000 m (42,500 ft), breaking the previous record of 11,248 m (36,902 ft) set in 1954.
Over 20 variants of the P-51 Mustang were produced from 1940 to after the war.
|Mustang I||620||Built for RAF at Inglewood, California|
|A-36 Apache||500||Dive-bomber variant of P-51; also known as "Invader" or "Mustang"|
|P-51||150||Built at Inglewood, California. 93 were Lend-Leased to the UK, operated by RAF as the "Mustang Ia". 57 were retained by the USAAF and fitted with Allison V-1710-39 engines.|
|P-51A-NA||310||Built at Inglewood, California. 50 Lend-Leased to the RAF as the "Mustang II".|
|XP-51B||2||Prototypes of P-51B|
|P-51B-NA||1,987||Built at Inglewood, California. First production version to be equipped with the Merlin engine. 308 supplied under Lend-Lease and operated by the RAF as "Mustang III".|
|P-51C-NT||1,750||First P-51 variant to be built at North American's Dallas plant. Identical to P-51B. Mustangs built by North American in Dallas were suffixed "-NT". 636 were supplied under Lend-Lease to the RAF as the "Mustang III".|
|XP-51D||3||Prototypes of P-51D|
|P-51D-NA/-NT||8,200||6,600 built at Inglewood and 1,600 built at Dallas. 100 P-51D-1-NA were sent unassembled to Australia. 282 under Lend-Lease served in the RAF as the "Mustang IV".|
|XP-51G||2||Lightweight version; five-bladed propeller|
|P-51H-NA||555||Built at Inglewood, California|
|XP-51J||2||Allison-engined lightweight development.|
|P-51K-NT||1,500||Built at Dallas, Texas. Identical to the P-51D except fitted with a four-bladed Aeroproducts propeller. 600 Lend-Leased to the RAF as the "Mustang IVa".|
|P-51M-NT||1||Same as P-51D-25-NT and P-51D-30-NT, but with the non-water injected V-1650-9A engine for low-altitude operations and sharing the cuffless Hamilton Standard propeller. It was intended to enter full production at Dallas, but the contract was later cancelled.|
|Total number built||15,588||Includes 100 sent unassembled to Australia|
|Commonwealth Aircraft Corporation CA-17 Mustang Mk 20||80||100 unassembled P-51D-1-NA were delivered as kits to Australia, but only 80 were built.|
|CAC CA-18 Mustang Mk 21, Mk 22 and Mk 23||120||License production in Australia of 120 (170 were originally ordered) P-51D. The Mk 21 and Mk 22 used the American-built Packard V-1650-3 or V-1650-7 engine and the Mk 23 (which followed the Mk 21) was powered by a Rolls-Royce Merlin 66 or Merlin 70 engine.|
|Total number built||200|
|TP-51C||At least 5||Field modification to create dual-control variant; at least five known built during World War II for training and VIP transport.|
|ETF-51D||1||One P-51D modified for use on an aircraft carrier.|
|Rolls-Royce Mustang Mk X||5||Five prototype conversions only – two Mustang Mk I airframes were initially trial fitted with Rolls-Royce Merlin 65 engines in mid-late 1942, in order to test the performance of the aircraft with a powerplant better adapted to medium/high altitudes. The successful conversion of the Packard V-1650 Merlin-powered P-51B/C equivalent rendered this experiment as superfluous. Although the conversions were highly successful, the planned production of 500 examples was cancelled.|
|NA-133||P-51H for the U.S. Navy, with folding wings, an arrestor hook and tip tanks.|
|CAC CA-21 Mustang Mk 24||License production of 250 two-seater Mustangs.|
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 radio-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, Loehle 5151 Mustang and ScaleWings SW51 Mustang.
Aircraft of comparable role, configuration, and era