History

In April 1940 the British Purchasing Commission negotiated with North American Aviation to design and build an advanced fighter for the RAF. Because of the serious situation in Europe, it was stipulated that a prototype must be fully completed within 120 days ! At all the plane was completed only in 117 days, but because the new 1100 hp Allison engine was behind scedule, the first flew of the prototype NA-73X took place in the end of October 1940. Only seven months later, in May 1941, the firt production example was ready.

The plane, named Mustang I by the RAF, was immediately put under evaluation, and it was noticed to be far superior to any US fighter then extant. It was fast and highly manoeuvrable at low levels, but it's performance decreased rapidly at higher altitudes. Many of the RAF planes were therefore equipped with obliquely-mounted cameras for tactical reconnaissance missions and in groud-attack duties. Finally the RAF had 23 Squadrons equipped with Mustang I, which has an armament of 4 x 12,7 mm kk and 4 x 7,62 mm kk.

Also a dive braked version, A-36A Apache, was built. It was equipped with 1325 hp Allison engine and with 6 x 12,7 mm mg and bombracks under wings. The US Army ordered 500 of them to use them as dive bombers in close air support missions. These were the first Mustangs to see combat in USAAF. The next version was P-51A, which has 1200 hp Allison engine. It was armed with 4 x 12,7 mm mg and could also carry two bombs or two drop tanks. 50 of them were in use in the RAF and they were named as Mustang II.

Soon after the first Mustang Is were received in Britain in 1942, it was decided to make experimental installations of Rolls-Royce Merlin 61 and 65 engines in Mustang airframe to make better the poor high altitude performance. The installations were planned and made by the Roll-Royce in Hucknall. After six weeks, in autumn 1942, the modifications had been completed and the first test flights made, demonstrating a huge improvement in performance at high altitudes. The USAAF was impressed by the increased performance of the plane, ordering large numbers of Merlin-engined Mustangs. The numbers were so large that North American's factory at Inglewood cold not cope alone, and a new production line was established in a new plant at Dallas.

Inglewood began production of the new Merlin-engined P-51B model in the summer of 1943 and the production of the identical P-51C version started in Dallas. Both of these differed from the earlier P-51/P-51A in having a strengthened fuselage, new ailerons and many detail changes. Armament comprised 4 x 12,7 mm mg. A total of 1988 P-51Bs and 1750 P-51Cs were built before both production lines turned over to construction of the P-51D. No fewer than 21 RAF squadrons used the plane which was named Mustang III. The rear view was poor and the Mustang IIIs were equipped with the so called Malcolm canopy by the RAF. The operational service with the USAAF began by the 8th Air Force in Britain in December 1943, when the P-51B/P-51Cs with drop tanks began to escort the US bombers on daylight missions deep in to the German homeland. Equipped with two 500 litres drop tank the planes could fly from England to Berlin and back escorting the heavies with their long-range bombing missions that lasted 7 or 8 hours. About the same time the 10th Air Force in Burma and the 15th Air Force in Italy came operational. Totally the USAAF had 2828 P-51B/P-51Cs in use.

The most produced variant was P-51D with 7956 planes, of which 6502 come from Inglewood. The P-51D introduced a buble canopy to provide the pilot with an exellent allround view, a modified rear fuselage, an armament of 6 x 12,7 mm mg and bomb racks. Later production aircraft introduced as standard a small dorsal fin to compensate for a loss of rear fuselage profile surface resulting from the cocpit modification. 1100 planes were equipped with launch rails for 127 mm rocket projectiles. P-51Ks followed, these differing only by a change in propeller and 1500 were produced. The RAF had 281 P-51D and 594 P-51K, they all designated Mustang IV.

The next version was P-51H which was 40 per cent lighter than P-51D. Equipped with V-1650-9 Packard Merlin engine, generating 2218 hp, the plane had maximum speed of 784 km/h. 555 were produced before the war ended and the production was cancelled.

The P-51D "Petie 2nd" was flown by Ltn Col John C Meyer in 487. Fighter Squadron 352nd Fighter Group, in autumn 1944 when he was the commanding officer of the squadron. Two of his 24 kills in the Second World War was achieved in this plane. Later in Korea he was credited with two kills.

Technical data of P-51 D Mustang

Powerplant	1695 hp Packard Merlin V-1650-7
Dimensions	Span 11,28 m; lenght 9,83 m; height 2,64 m; wing area 21,65 m2
Weights	Empty 3232 kg; max. take off 5488 kg
Performance	Max. speed 703 km/h (7620m)
Armament	6 x 12,7 mm Colt-Browning mg (D and K models); 6 x 127 mm rocket or 2 x bomb (max. 454 kg)
Production	15586 (all versions)
Users	USAAC/USAAF, SAAF, RNZAF, RCAF, RAF, RAAF, Netherlands, FFAF, China

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