Untitled Document

The American Fighter

Threeway view if the P-51D. Picture From Ace Pilots
P-51 Mustang

In the beginning of 1940 the British were shopping for a combat fighter that would be able to excel in the requirements that combat had shown to be essential. The British asked North America if it would produce a fighter with British specifications of: an armament of eight machine guns, armor protection for the pilot, self sealing fuel tanks and an inline engine, the last part was to try and keep with all British single-engine fighters of the period. This all had to be completed within 120 days.

The prototype NA-73 was ready three days before the deadline. It could quickly be seen that it possessed exceptional lines, with laminar-flow wings, low drag fuselage features, and an overall cleanliness of airframe. The prototype made it’s maiden flight in October 1940 and entered immediate production, with the first deliveries beginning in December. The Mustang I aircraft had an armament of four .30 inch and two .50 inch machine guns in the wings and two .50 inch guns in the fuselage.

Prototype NA-73. Picture From P-51

As part of the original export permission, it had ben specified that two NA-73'sshould be supplied to the U.S. Army for evaluation and fourth and tenth aircraft were handed over as XP-51's. The USAAF ordered 150 of this model to be armed with four 20mm cannons so they could be supplied to Great Britain as Mustang IA’s under the lend lease, but after the attack on Pearl Harbor, the USAAF kept some examples.

The first model ordered for the USAAF themselves was the A-36A, a ground attack version which first flew in September 1942. Armament consisted of six .50 inch guns in the wings and two 500lb. Bombs under the wings, deliveries of the 500 ordered were complete by March 1943. Because of the type of engine in the early models the first Mustangs were used as a low-level ground attacks by the USAAF and the RAF. But there was an urgency to giving the Mustang a powerful engine so it could deliver it’s power at high altitude. A partial solution was found in the Allison V-1710-81, it was used in the P-51A and delivered 1,200 hp. There would be a total of 310 ordered in 1942. The new engine had only partially solved the problem of the Mustang’s lack of adequate performance above medium altitude. The new solution to this problem would be in a British proposal to abandon the Allison engine in favor of the Rolls Royce Merlin. Experimental installations would be carried out both in the U.S. and Britain with engines being built in both countries. Conclusive trials had shown that the Merlin boosted the Mustang’s top speed by 50 m.p.h. and generally altered the type’s high altitude performance out of all recognition, results were concluded September 1942. Two identical types would be built both in California and in Texas the P-51B and the P-51C. At first they were installed with 1,300 hp V-1650-3 engines but would be replaced with the V-1650-7 engines which produced 1,645 hp. Armament for both would be four 20mm cannons but altered to six .50 inch guns. Drop-tanks could be carried extending the range of the Mustang to 2,080 miles.

The next version of the Mustang the P-51D would be built in greater numbers then all other versions put together. The main feature was the cockpit, allowing the pilot to see with greater vision in all directions. The rear fuselage was cut down, and smoothly lined one-piece perspex canopy was fitted in place of the earlier framed hood. The armament was the standard six gun as was the V-1650-7 engine. Production of the P-51D was 7,956 aircraft, 280 of these would be sent to the RAF as Mustang IV.

The final production model was the P-51H with power provided by a 2,218 hp V-1650-9 engine. The cockpit would be shortened, extra fuel tankage provided and a taller fin and rudder assembly fitted. The P-51H would be 1,100 lbs. Lighter then the P-51D and was the fastest at a speed of 487 m.p.h. only 555 had been built before the other orders were canceled because the Japanese surrendered.

The Mustang was in every respect a great fighter. It was well loved by its pilots and the crews of the bombers it escorted and was feared by German and Japanese pilots. With its Merlin engine it possessed great speed, high rate of climb and excellent acceleration. With its exceptional lines it produced great manoeuverability and made its type one always to be remembered.