North American P-51D Mustang "Voodoo"

One of the most iconic fighters to come out of World War II, the P-51 Mustang, came about as a result of the desperate need of the British for fighters in 1939, as the war began. British industries were already at capacity producing the Hurricane and Spitfire, and of the American fighters being made or planned, the RAF only saw the P-40 Warhawk as being able to fight the German Bf 109s. With Curtiss at maximum output building P-40s, the British approached North American, who had been trying to sell the RAF the B-25 Mitchell, with an offer to license-build P-40s. North American’s president, James Kindleberger, had a better idea: design and build an entirely new fighter based around the P-40’s Allison V-1710 engine. The RAF was willing to fund a prototype if it cost less than $40,000 and could be delivered by January 1941; the contract was signed in April of 1940. North American flew the first NA-73 prototype in October, only 178 days later.

 

Given the short time North American had gone from a blank sheet of paper to a flyable aircraft, one might expect that the NA-73 fell short of the requirements. It improved upon it. The RAF had only desired four .30 caliber machine guns; the NA-73 had that, plus an additional four .50 caliber machine guns (two in the wings with the .30s and two in the cowl). Despite its thin, highly aerodynamic fuselage, it had a large fuel capacity that could make it an escort fighter and an interceptor. Moreover, it incorporated two radical design features: one was mounting the radiator below the fuselage; besides saving space, it also allowed the pilot to force hot air out of the radiator to boost speed. The most radical was the use of a laminar-flow wing. Compressibility, where air going over a wing would reach supersonic speeds and cause the aircraft to accelerate out of control in a dive, was a minor problem in the P-40 and notorious on the P-38 Lightnings. With a laminar-flow wing, airspeed over the wings never reached supersonic speeds, preventing compressibility without sacrificing maneuverability. The RAF eagerly accepted the design as the Mustang Mk. I and it entered production in mid-1941.

 

When the RAF began operating the Mustangs in combat, however, they found that the fighter, while able to maneuver with even the Focke-Wulf 190 and having plenty of range, was sluggish and slow above 15,000 feet. This was due to the V-1710 engine, which had never been designed for high-altitude performance. North American had experienced misgivings about the V-1710, but it had been part of the specification—the Mustang Mk. I was useful in low-level roles, especially reconnaissance, and the USAAF took an interest in it as a ground-attack aircraft, ordering 500 as the A-36A Apache.

 

In April of 1942, a Rolls-Royce technician got to fly a Mustang Mk. I and he was suitably impressed by its maneuverability. He was interested in whether or not a bigger engine could be used on the aircraft, and five Mustangs were turned over to Rolls-Royce to be equipped with a Merlin engine and a propeller adapted from the Spitfire Mk. IX. The test pilots were stunned by the increase in performance: above 15,000 feet, the Merlin-engined Mustang not only retained its agility and range but its speed was increased to 433 mph and the ceiling to 40,000 feet. North American learned of these tests and embarked on a redesign process, culminating in the P-51B: this had a strengthened fuselage and wider radiator for the more powerful Merlin; the armament was reduced to save weight to four (later six) .50 caliber machine guns in the wings. With drop tanks fitted under the wings, the P-51Bs could fly virtually anywhere in Europe. The Mustang had finally realized its full potential, and the USAAF, which had been taking catastrophic losses to bombers over Germany due to the lack of long-range fighters, now had one.

 

The P-51Bs began reaching Europe by August of 1943, and when they reached the 8th Air Force in numbers by late 1943, the situation in the air over Europe started to change. While P-51 pilots loved the responsiveness and speed of the Mustang, a few problems did crop up: the gunsight was challenging to use, the guns tended to jam, the glycol cooling system for the engine was easy to hit and would doom the P-51 instantly, and the P-51B lacked vision to the rear. The type also showed a propensity to go into uncontrollable snap rolls at high angles of attack. In response, North American designed the P-51D, which solved most of the problems: it had a cut-down rear fuselage and incorporated a bubble canopy, giving the P-51D the best visibility of any fighter of the war; the adoption of the K-14 gunsight was much easier to use and more accurate; the machine guns were set upright and spaced along the dihedral of the wing rather than along the path of flight, making them more accurate as well and mostly curing the jamming problem (high-G turns could still jam the guns); the snap-roll problem was fixed by adding a fin fillet to the tail. Nothing could be done about the glycol system, and more P-51s would be lost to ground fire hitting the glycol tanks than any other reason. (This was the primary reason the P-47 Thunderbolt, with its radial engine, took on the bulk of ground attack missions, leaving the P-51s as the primary escort fighters).

 

The P-51s would bear much responsibility for swatting the Luftwaffe from the air. It could outperform the Bf 109 in all respects, and even with an Fw 190 below 15,000 feet—above 20,000 feet, the Mustang had the advantage. Nearly 5,000 German aircraft would be shot down by P-51s, the highest total claimed by any Allied fighter during WWII. Almost 1,000 more Japanese aircraft could be added to that total as P-51Ds began reaching the Pacific in 1944, acting as escorts for the B-29 bombers. Many aviation historians generally consider the P-51 Mustang as one of the finest fighters of World War II and, by some, the most pure fighter of all time.

 

After WWII ended, North American began the production of “lightweight” P-51Hs, which used lighter construction materials, lengthened the fuselage for better performance, and raised the tail for better aerodynamics. The Merlin engine was modified with a new water-injected supercharger. While not as aesthetically attractive as the P-51D, the P-51H was among the fastest piston-engined aircraft ever built, with a top speed of only 120 mph below the speed of sound. Redesignated as the F-51 by the newly independent USAF in 1948, the Mustang’s combat duties weren’t finished yet. Though not suited for the role, the availability of aircraft meant that the F-51s would be used as ground-attack fighters throughout the Korean War. The P-51 had been exported to 55 nations during and after the war, and it would see service in the Arab-Israeli conflicts, various brushfire wars in Central and South America, and in the Philippines. The last F-51 in U.S. service (ironically, U.S. Army service) did not leave until 1968, while the Dominican Republic operated P-51s as frontline fighters until 1984. Out of over 16,700 P-51s produced, over 250 survive today, with nearly 140 flyable examples, making the P-51s among the best-preserved World War II-era aircraft types ever.

 

Meet the fastest piston-engined aircraft in the world! "Voodoo" started life as BuNo 44-73415, a P-51D delivered to the USAAF at the tail end of WWII. In 1951, it was supplied to the RCAF and flew with an unknown Canadian unit until 1959. When 44-73415 was retired, it was bought by a warbird collector and would go through the hands of several owners between 1959 and 1994, suffering two accidents in the meantime. In 1994, it was modified with a new, far more streamlined fuselage and smaller canopy and entered the racing circuit at Reno as "Pegasus." In 1998, "Pegasus" was bought by another famous racer, Bob Button, and renamed "Voodoo."

 

"Voodoo" would fly at several Reno Air Race events in the Unlimited Class, but it wasn’t until 2013 that it won, with Steve Hinton at the controls. It won again in 2014 and 2016. In 2017, however, Button and Hinton set their sights on another trophy: the title of fastest piston-engine aircraft. In September of that year in Challis, Idaho, Hinton set the record at 554 mph, with an average speed of 531 mph. With no more worlds to conquer, it was decided to retire "Voodoo," and the aircraft was donated to Planes of Fame in 2018. "Voodoo"/44-73415 is still flyable, and even though her racing days are numbered, she continues to wow the crowds at numerous airshows throughout the state.

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