At one point right after the end of the war, factory-fresh war surplus Mustangs were sold as scrap for as little as $200 each. In the mid-50's a flyable example would bring an astonishing $2500. Today, a flying Mustang will fetch upwards of three quarters of a million dollars.
* * * *
North American P-51 Mustang (Part 2)
By Joe Baugher
On March 11, 1941, the Lend/Lease Act was passed by Congress, permitting the "lending" of American-built aircraft to nations deemed "vital to the security of the United States". On September 25, 1941, the US Army ordered 150 Mustangs under the provisions of Lend-Lease for delivery to Britain. All previous RAF Mustangs had been direct purchases by Britain.
These aircraft were designated Mustang Mark IA by the RAF and NA-91 by the factory. The RAF serial numbers assigned to this lot were FD418/FD567. For contractual purposes, these aircraft were assigned the US designation of P-51, and the Allison V-1710-F3R engine was given the US Army designation V-1710-39. The P-51s were assigned the USAAF serials 41-37320/37469. The Mustang IA differed from earlier versions in having the machine guns replaced by four 20-mm wing-mounted Hispano cannon, with long gun barrels protruding well ahead of the wing. Throughout 1941, the Army referred to these aircraft under the name *Apache*, but this was changed to *Mustang* at about the time the deliveries first began in mid-1942.
The British did not get all of these NA-91s. Since the RAF deliveries of the Mustang IA began after Pearl Harbor, many of them were repossessed by the Army before they ever got to Britain. FD418/FD437, FD450/FD464, FD466/FD469, and FD510/FD527 were diverted from the RAF order and delivered to the US Army. These were the first Mustangs to serve with the Army. The Army planes were fitted with two K-24 cameras in the fuselage. Some were fitted with four 0.50-inch machine guns, but most retained their quartet of 20-mm cannon. Most retained their RAF camouflage and serial numbers, although some were indeed painted with their equivalent USAAF serials. These were designated as tactical reconnaissance aircraft and were designated F-6A, but this designation was soon changed to P-51. One was coverted as P-51-1 (42-37320), and the rest were converted as P-51-2. The serial numbers of the Mustang IAs that were diverted to the USAAF were 41-37320/47339, 41-37352/37366, 41-37368/37371, and 41-37412/37429.
In March of 1943, a batch of 25 F-6A/P-51s were assigned to the 154th Observation squadron at Oujda in French Morocco. This was the first US Mustang unit. The first mission was a photographic coverage of Kairouan airfield in Tunisia on April 10, 1943.
Two P-51 airframes were diverted to the XP-78 project, about which much more will be said later!
In 1940, the US Army had given its permission for the initial British Mustang delivery to proceed, with the proviso that two of the NA-73s destined for England be made available to the Army for tests free of charge. In a separate contract dated September 20, 1940, the two aircraft delivered to the Army were to be the fourth and tenth production NA-73s, and the planes were to be designated XP-51.
The fourth and tenth NA-73s were duly delivered to the US Army in May of 1941 for testing at Wright Field, Ohio. They bore the designation XP-51 and were assigned the serial numbers 41-038 and 41-039. They were initially unpainted except for national insignia and the black antiglare panel over the forward fuselage ahead of the pilot. The Army painted the serials 1038 and 1039 on the fin and on each side of the nose, together with the WRIGHT arrowhead emblem on the rear fuselage. Much later, they were both painted olive drab overall.
The testing of the two Wright Field XP-51s was rather slow at first, almost as if the Army didn't really want to bother with these airplanes and that they were some sort of nuisance that the Army wished would just go away. Some authors have suggested that there were dark and evil motives behind the Army's reluctance to test the XP-51s. However, the slow pace of the testing of the XP-51s can probably be blamed more on bureaucratic inertia than on anything all that sinister. At that time, the Army was overloaded with other test programs, the Lockheed P-38 Lightning, Bell P-39 Airacobra, and Republic P-47 Thunderbolt being thought to meet all the Army's requirements for fighter aircraft. Furthermore, the Mustang was a "foreign" type not built to any American specification, and was therefore way down on the Army's list of priorities.
Nevertheless, the testing of the XP-51s did eventually get underway at Wright Field, and the Army's test pilots reported very favorably on the performance of these planes. Inexplicably, no Army orders were forthcoming. Much later, the Senate Special Committee to Investigate the National Defense Program (better known as the "Truman Committee", after its chairman Sen. Harry S Truman of Missouri) was given the task of investigating the system under which military production contracts were awarded during wartime conditions. They looked specifically into the reason why the Army had sat on its hands for so long before ordering any examples of the Mustang, an airplane which had such demonstrably superior performance.
Some insiders claim that NAA President "Dutch" Kindelberger had been asked to pay bribes in exchange for a production contract, but that he had refused all such demands in no uncertain terms. The primary cause of the long delay in Army acquisition of the Mustang may be somewhat less sinister. The Mustang may have been the victim of the "Not Invented Here" (NIH) syndrome, in which the Army looked askance at an upstart aircraft which had not been designed in response to any of its official requirements.
Only after Pearl Harbor did the US Army finally agree to order the Mustang for its own use. General H. H. "Hap" Arnold, Chief of Staff of the USAAF, was instrumental in breaking up the bureaucratic log-jam and getting the Army to relent and order the Mustang for its own use. On April 16, 1942, the Army finally ordered 500 NA-97s. The NA-97 was a ground attack version and was designated A-36A (in the attack series rather than the fighter series) and was assigned the name *Invader*. Serial numbers were 42-83663/84162.
The A-36A differed from previous Mustang versions in having a set of hydraulically-operated perforated door-type dive brakes mounted at approximately mid-chord on both the upper and lower wing surfaces outboard of the wing guns. Underwing racks were fitted for two 500-pound bombs. A built-in armament of six 0.50-inch machine guns (two in lower fuselage, four in the wings) was fitted. The engine was the Allison V-1710-87, rated at 1325 hp at 3000 feet. Normal and maximum loaded weights rose to 8370 pounds and 10,700 pounds, and the maximum speed in clean condition fell to 356 mph at 5000 feet and 310 mph with the two 500-lb bombs fitted. With the bombs, range and service ceiling were 550 miles and 25,100 feet respectively.
The first A-36A flew on September 21, 1942. Deliveries of the Invader were completed by the following March. The Invader equipped the 27th and 86th Fighter Bomber Groups based in Sicily and in Italy. They initially were painted in olive-drab and light-gray finish and were painted with yellow wing bands and yellow circles around the national insignia. Both of these Groups arrived in North Africa just after the end of the Tunisian campaign. They saw their first action during aerial attacks on the island of Pantelleria. The A-36A was involved in the taking of Monte Cassino, and participated in the sinking of the Italian liner *Conte di Savoia*.
Several sources list the Invader as not being particularly effective during combat. It seems that this is not strictly correct. Although losses during low-level attacks were rather high, the A-36 was actually a good dive bomber and it was a stable and effective ground strafer. The engine was very quiet, and it was often possible for an A-36 to get nearly on top of an enemy before he realized that an attack was imminent. Dive bombing was usually initiated from an altitude of 10,000 feet to 12,000 feet, with bombing speed held to around 300 mph by the dive brakes. The bombs were dropped at an altitude of 3000 feet, and pullout was at approximately 1500 feet. The Invader was fairly rugged and easy to maintain in the field. The A-36A was able to take a considerable amount of battle damage and still return to base.
The A-36s did not see very much air-to-air combat, since it was generally believed that it was no match for the Bf 109 at high altitudes and that it was therefore best for A-36 pilots to avoid such encounters if at all possible. If air-to-air combat was unavoidable, it was thought best to force the battle down to altitudes below 8000 feet, where maximum advantage could be taken of the A-36A's excellent low-altitude performance. Although it was not a fighter, the Invader claimed 101 enemy aircraft destroyed in air-to-air combat.
A sort of urban legend has sprung up about the A-36A's dive brakes. According to some stories, the dive brakes of the A-36A were next to useless and were deliberately wired shut at the manufacturers so that they could not be used. This story is totally incorrect. On the contrary, the dive brakes proved to be quite effective in combat. The origin of this legend seems to have been in the United States, at a time before the Invaders first went overseas. It seems that A-36A pilots were told by their officers in the USA that their dive brakes would be all but useless in combat and it would be best if they simply wired them shut. This turned out to be incorrect, and the dive brakes were used to great effect throughout the Sicilian campaign and the Italian invasion.
One A-36A was supplied to the RAF in March of 1943 for experimental purposes. Its RAF serial number was EW998.
A-36A Ser No 42-83665 is on display at the WPAFB Museum in Dayton, Ohio. This may be the sole surviving Invader.
The next Army contract for Mustangs consisted of an order on August 24, 1942 for 1200 NA-99 versions with the USAAF designation of P-51A. Unlike the A-36A, these aircraft from the start were meant to be fighters, not bombers. The first P-51A flew on February 3, 1943, and the first deliveries began the next month. In the event, only 310 P-51As were actually built between March and May of 1943 before production was switched over to the Merlin-powered P-51B.
These aircraft had the same external stores capability as the A-36A Invader, but had no dive brakes and no fuselage guns, the armament being limited to four 0.50-inch machine guns mounted in the wings. The inboard pair had 350 rpg and the outboard pair had 280 rpg. An under wing load consisted of two 250 lb, 325, or 500-pound bombs. Maximum takeoff weight rose to 10,600 pounds, but maximum ferry range was increased to 2350 miles. The P-51A had the Allison V-1710-81 engine rated at 1200 hp for takeoff and 1125 hp at 18,000 feet, with significantly better high-altitude performance than the V-1710-39 of the P-51.
Because of the thin wing cross section, the wing guns lay almost on their sides and the ammunition belt feeds had to be built with some rather sharp kinks in them in order to direct the bullets into the guns. This awkward arrangement resulted in many gun jams, particularly after maneuvers in which high g-values were pulled.
Three production blocks were built with the following serials:
43-6003/6102 P-51A-1-NA
43-6103/6157 P-51A-5-NA
43-6158/6312 P-51A-10-NA
Of the 310 P-51As built, 35 of them were fitted with twin-K24 camera installations and had their guns removed. These were redesignated F-6B.
Another 50 examples went to the RAF, becoming Mustang IIs. These planes replaced the NA-91s diverted from RAF Mustang IA orders for conversion as USAAAF F-6As. The RAF serials of the Mustang IIs were FR890/FR939. Deliveries were made late in 1942. Mustang II FR901 was fitted with special deep-section fuel tanks beneath the wings for ultra-long-range flying.
One P-51A was given to the US Navy for evaluation (BuAer #57987).
Specifications of P-51A-10-NA:
One 1200 hp Allison V-1710-81 twelve-cylinder Vee liquid cooled engine. Maximum speed was 340 mph at 5000 feet, 360 mph at 10,000 feet, 380 mph at 15,000 feet, and 390 mph at 20,000 feet. Range on internal fuel was 750 miles at 300 mph at 10,000 feet. Range with two 125 Imp. gall. drop tanks was 2000 miles at 266 mph and 2350 miles at 228 mph. An altitude of 5000 feet could be attained in 2.2 minutes, 10,000 feet in 4.4 minutes, and 20,000 feet in 9.1 minutes. Service ceiling was 31,350 feet. Weights were 6433 lbs empty, 8600 lbs normal loaded, and 10,600 lbs maximum loaded. Wingspan was 27 feet 0 1/4 inches, length was 32 feet 2 1/2 inches, height was 8 feet 8 inches, and wing area was 233 square feet.
The first P-51A group was the 54th, which remained in Florida for replacement training. Later, P-51As went to Asia with the 23rd, 311th, and 1st Air Commando Groups. Almost all of the P-51As served in the China, Burma, India (CBI) theatre of operations. On November 25, 1943, the 530th Fighter-Bomber Squadron of the 311th Fighter Bomber Group flew the first of the Mustang's long-range escort missions, using drop tanks to escort B-24 Liberators in an attack on Rangoon, Burma, a round trip of nearly 900 miles.
The F-6Bs, on the other hand, served in Europe, mainly with the 107th Tactical Reconnaissance Squadron based in England.
Sources:
American Combat Planes, Ray Wagner, Third Enlarged Edition, Doubleday, 1982.
The American Fighter, Enzo Angelucci and Peter Bowers, Orion Books, 1987.
War Planes of the Second World War, Fighters, Volume Four, William Green, Doubleday 1964.
United States Military Aircraft since 1909, Gordon Swanborough and Peter M. Bowers, Smithsonian, 1989.
Fighting Mustang: The Chronicle of the P-51, William N. Hess, Doubleday, 1970.
Classic Warplanes: North American P-51 Mustang, Bill Gunston, Gallery Books, 1990.
Famous Fighters of the Second World War, Volume I, William Green, 1967.
British Military Aircraft Serials, 1912-1969, Bruce Robertson, Ian Allen, 1969.
Joe Baugher
AT&T Bell Laboratories
2000 North Naperville Road
Naperville, Illinois 60566-7033
