Inspiration Chino Air Museum: Evolution Of The Mustang

Evolution of the Mustang

By Jim Dunn

One of the great things about a visit to the Planes Of Fame Air Museum in Chino, Calif., is not only the opportunity to view some of the most famous warplanes in aviation history, but also to be able to visually examine the evolution of aerial warfare from World War I through the Vietnam era.

In some cases this large collection also allows the visitor a chance to see how certain types of these aircraft have developed from one model to the next, sometimes even changing missions as they evolved. The best example of this can be seen in the development of America’s greatest fighter of World War II, the North American P-51 Mustang.

It was the British Purchasing Commission in May 1940 who would be the first to place an order with North American for their proposed model NA-73. Desperate for fighter aircraft the British had a provision in the contract that gave North American only 120 days to design and build the prototype. Amazingly on the 100th day after signing a ceremonial roll-out of the nearly complete airframe was held at the North American facility in Inglewood, California.

Needing a name for the new fighter the British Air Council came up with the name Mustang in recognition of American aggressiveness. However, the non-supercharged 1,100 hp Allison V-1710 engine in these Mustang Is would begin to loose its aggressiveness above 12,000 feet of altitude, and for RAF Fighter Command this was unacceptable.

If the RAF didn’t want these aircraft then the new Army Co-operation Command did. Their idea for these Mustang Is were to use them to support ground forces in the low level fighter/reconnaissance mission. It would be in this role that the Mustang would fire its first shots in anger on May 10, 1942 during a reconnaissance flight over an airfield in France.

Not wanting the Mustang themselves the USAAC was forced by an Act of Congress meant to support the Lend-Lease Program to accept 150 British ordered Mustangs as their first P-51 model. Lacking a fast reconnaissance aircraft of their own the USAAC converted 55 of these Mustangs and sent them to observation units after the attack on Pearl Harbor. This P-51 model was armed with four 20 mm cannons, with the reconnaissance version also equipped with two K-24 cameras mounted in the fuselage. The photo reconnaissance version of the Mustang would later be designated the F-6.

While improvements were being made to the P-51 reports from England on the low level capabilities of the Mustang led North American to offer an attack version to the USAAF. Designated the A-36A it was given the name Apache, which had been the name the USAAF was going to give the P-51 when it entered US service.

The 500 A-36As produced for the USAAF featured hydraulically operated dive brakes above and below each wing, and bomb shackles to carry a 500 lb. bomb under each wing. Changes from the Mustang I included installation of a 1,325 h.p. V-1700 engine, and replacing the two 0.30 inch guns in each wing with the heavier caliber 0.50 inch guns. In the Mustang I and A-36A two 0.50 inch guns were also installed in the fuselage under the engine.

Last of the Allison powered Mustangs was the P-51A of which only 310 were ordered by the USAAF in 1942. These aircraft had the 1,200 hp V-1710 engine, and were equipped with only four 0.50-inch guns. They also retained the bomb racks, which could now be used to carry external fuel tanks. The P-51A saw the majority of its service in the China-Burma-India theater, while the P-51 and A-36A were in North Africa and the Mediterranean.

At Planes Of Fame you can view their rare airworthy P-51A 43-6251 named Mrs. Virginia, while A-36A 42-83731 has just been restored to flight for owner Tom Friedkin by Fighter Rebuilders. Both of these Allison powered aircraft can be distinguished from later Merlin powered Mustangs by the small air duct atop the engine.

The Mustang would become a true fighter once and for all time with the installation of the Rolls-Royce Merlin engine beginning in the P-51B model. License built in the United States by the Packard Motor Company the V-1650-3 with a two-stage supercharger produced 1,380 hp in the P-51B and C models. Both of these models were armed with four 0.50-inch guns, but they could now carry up to a 1,000-pound bomb under each wing. The only real difference between the two models is that the P-51B was built in Inglewood, while the P-51C was built in Dallas, Texas.

Though there were 1,988 P-51B models built, and another 1,750 P-51C models produced in Dallas, it would be the next model of the P-51 that would forever define the profile of the Mustang. That model was the P-51D.

Featuring a redesigned fuselage, a thinner wing, the Packard 1,490 hp V-1650-7 engine, and now equipped with six 0.50-inch guns, the P-51D entered production in February 1944. Perhaps the most important change in the P-51D was the introduction of the rearward-sliding “bubble” canopy. Compared to the former “birdcage” canopy on the earlier models visibility was increased ten-fold with the “bubble”.

While the P-51B would lead the way in Europe being the first Mustang to reach Berlin in March 1944, it was the P-51D that came to rule the skies over both Germany and later Japan.

In a production run that lasted less than two years North American produced 6,502 P-51Ds at Inglewood and 1,454 at Dallas. Another 1,337 P-51Ks that featured an Aeroproducts propeller in place of the Hamilton-Standard type were also built in Dallas.

Merlin powered Mustangs can also be seen at Planes Of Fame in Chino. The museum owns two P-51Ds including serial number 45-11582 that is named “Spam Can,” and a former Indonesian Air

Force P-51D with an unknown USAAF serial number. This later aircraft named Wee Willy II has been officially assigned the former identity of the famous Griffon powered Mustang racer the Red Baron that had crashed in Reno in 1979.

Others Mustangs such as Tom Friedkin’s beautiful P-51C 43-25147 named Princess Elizabeth can often be seen while visiting the museum. With Fighter Rebuilders located within the facility there is no telling what famous aircraft may be glimpsed.

For those into aviation history, or for those looking for a great place to learn it, the Planes Of Fame in Chino is worth the trip.