by David Buckingham

The Allied Purpose in the Air War

The Allies knew that they had to drive German industry into the ground in order to win the war. Since the factories, refineries, assembly-lines, and other industry-related structures were all inland, the only way to destroy them was by sending in bombers. The only way that the bombers could achieve real success was by gaining air superiority, which meant that nearly all of the bombers would be able to drop their bombs without being harassed by fighters, and return home to fight another day.

The problem with this sequence was that the Allies did not have this superiority, (Bailey 28) because their bombers were consistently getting shot down in fairly large numbers, by the German fighters that kept coming. The Allies soon realized that in order to gain this superiority, they would have to destroy more German fighters. In order to destroy the fighters, they would have to be forced into the air in greater numbers. In order to get more German fighters into the air, the more sensitive German industries would have to be attacked with more aggression.

Following this logic, the Allies began an intensified bombing effort that resulted in the famous bombings of Hamburg (July 24-28, 1943) and Ploesti (August 1, 1943), among others. And, indeed, this did cause more fighters to come up to meet and engage the bombers. Unfortunately, the bombers were overwhelmed by the German opposition, and their losses soon began to increase. (Copp 359) The Allied air forces had, in effect, pushed a stick into a hornets' nest, hoping to kill the hornets when they came out, and been stung by the ferocity of their response.

The Battle at Schweinfurt

The culminating point of this backfiring plan was the second bombing raid on Schweinfurt, which occurred on October 14, 1943. Schweinfurt was the location of huge ball-bearing factories that supplied most of the ball-bearings for the entire German military.

The U.S. Eighth Air Force had staged a fairly successful raid on the same city two months earlier, but the second time around, the Germans were ready for them. The official report afterwards said that the Luftwaffe "turned in a performance unprecedented in its magnitude, in the cleverness with which it was planned, and in the severity with which it was executed."

Of the 229 bombers that actually made it all the way to Schweinfurt, 60 were shot down, and 17 more made it home, but were damaged beyond repair. This was a 26.5% battle loss rate for the Americans, while the Germans only lost 38 airplanes the whole day, from all causes. (Boyne 327) This battle was one of the key battles of the war, and undeniably proved to the Allies that the bomber offensive could not continue without a long-range fighter escort. (Copp 444) Even before October of '43, some had begun to realize the need for this kind of fighter. In June, the Commanding General of the Army Air Forces, General Hap Arnold, wrote a memo to his Chief of Staff, Major General Barney Giles, which said:

This brings to my mind the absolute necessity for building a fighter airplane that can go in and out with the bombers. Moreover, this fighter has got to go into Germany. . . . Whether you use an existing type or have to start from scratch is your problem. Get to work on this right away because by January '44, I want a fighter escort for all our bombers from the U.K. into Germany. (Copp 413-414)

Click to continue

The Development of the P-51

In April of 1940, "Dutch" Kindleberger, president of North American Aviation, visited Sir Henry Self, the head of the aircraft division of the British Purchasing Commission, asking if Britain would like to buy some of his B-25 bombers. Self was not interested in buying any more bombers, but was interested in buying a good fighter.

He directed Kindleberger to the Curtiss company, who had a new fighter design, but were too busy building P-40's to do anything with it. Kindleberger went to Curtiss and bought their design for $56,000. He promised Self to have the planes ready by September of 1941. The prototype of the NA-73, as it was called, was ready to fly in October of 1940 and proved to have an excellent design.

The NA-73 had a revolutionary wing design that allowed it to fly at high speeds without adverse compression effects. In other planes, as they approached a certain speed, usually around 450 mph, the air would be flowing around the wing at nearly the speed of sound, putting huge amounts of pressure on the wings, which were unable to deal with the stress. The NA-73 did not have this problem, which meant it could fly safely at much higher speeds.

Another revolutionary idea in the plane was the way heated air from the radiator was dealt with. The NA-73's engineers designed it to expel this air and boost the plane's speed by 15 or 25 mph. The engineers also worked especially hard on making the plane as aerodynamic as possible, and so they positioned the radiator in a new place, made the fuselage as narrow as possible, and set the cockpit low in the fuselage. (Perret 118-119)

It was at this point that an error was made that made the Mustang useless as a long-range offensive fighter. When the NA-73 was mass produced as the P-51, it was powered by a 1250 horspower, liquid-cooled Allison V-1710 engine, which did not have a supercharger and lost performance above 11,800 ft.

At high altitudes air pressure goes down, and so there is less oxygen in a given amount of air, which means that engines do not burn as cleanly, and so lose power. Superchargers compress air before it is pumped into the engine cylinders so that there is enough oxygen for the engine to function well. The early Allison-engined planes did not have the supercharger, and so were limited to low-altitude operations. Even without a high-altitude capability, the Mustang was an impressive plane and was bought in quantity by the RAF. It flew its first mission on May 10, 1942, against Berck-sur-Mer on the French coast. (Grant 17-18)

Go to Merlin Engines