Heavy losses over Germany became the norm in 1943. The attrition reached a peak on August 17 when the 8th Air Force attacked the fighter assembly plant at Regensburg and the ball-bearing factories at Schweinfurt. Of the 376 aircraft dispatched on the double raid, 60 were lost and many more written off. A second raid on Schweinfurt in October cost the Americans 77 aircraft lost and another 133 damaged out of 291 dispatched. After the second Schweinfurt raid, bombing operations were temporarily suspended. It was brutally clear that the bombers would have to be escorted to and from targets deep in Germany. However, there were no aircraft capable of fulfilling this role.
The USAAF’s P-38 Lightning and P-47 Thunderbolt fighters lacked the performance to meet enemy fighters on equal terms and the range to escort the bombers over Germany. The Luftwaffe could now choose the time and place to attack, even when the P-47’s range was extended by 490-liter (108-gallon) drop tanks. German fighters would often draw the P-47s into combat, at which point they would have to jettison their drop tanks and reduce their escort range. The P-38 had a longer range but poor performance over 6,000 meters (20,000 ft.), the altitude at which most combats over Germany took place.
Enter the Mustang
The crisis was resolved with the arrival of the North American P-51B Mustang in December 1943. Powered by the Rolls-Royce Merlin and fitted with a 340-liter (75-gallon) drop tank, the P-51B had a range of 1,000 miles (1.6 km), enabling it to fly escort to such targets as Emden, Kiel and Bremen. The bubble-canopied P-51D, which arrived in May 1944, had a boosted performance with reinforced wings, allowing exceptional fuel loads and, with drop tank, a range of 1,500 miles (2,400 km) sufficient for escort to any target and even for the shuttle missions that flew to the Soviet Union.
The P-51D matched the Me 109G in level maneuvering flight and had the edge in climb and dive. Only the rate of roll left the German fighter on equal terms. It could remain in the air for over nine hours. In the P-51D the USAAF possessed a superb escort fighter that it could use to provoke and win a series of air supremacy battles. In January 1944, the Americans had introduced a modified bomber support relay system, which remained standard for the rest of the war. Rather than flying to a predetermined rendezvous point and then accompanying part of the bomber stream until relieved by another unit, a group was allocated an area along the route, which it patrolled while the bomber stream passed through.
On May 30, 1944, 8th Air Force Mustang ace Major George Preddy wrote in his combat report:
As the bombers were approaching … Magdeburg, I was leading a section of seven ships giving close escort to the rear box which was quite a distance behind the main formation. I noticed 20 to 30 single-engine fighters attacking the front boxes, so we dropped our tanks and headed toward them. We came up behind three Me 109s in rather tight formation. I opened fire on one from 300 yards and closed to 150 yards. The 109 burst into flames and went down. I slipped behind the second 109 and fired while closing from 200 to 100 yards. He started burning and disintegrated immediately. He went down spinning. The third enemy aircraft saw us and broke down. I followed him in a steep turn, diving and zooming. I got in many deflection shots, getting hits on the wing and tail section. I ran out of ammunition, so my element leader, Lt. Whisner, continued the attack getting in several good hits. At about 7,000 feet the pilot baled out.
The most experienced P-47 groups were assigned those sectors where enemy opposition was anticipated, while the target leg of the bomber route was flown by P-38s and P-51s. The arrival of the Mustangs prompted another tactical adjustment of the bomber formations. They were reduced to three squadrons of 12 aircraft, with the lead squadron in the center and the trail squadrons formed up above and below. Although overall strength had been cut by one-third, the new formation occupied 17 percent more air space than its predecessor, reducing the strain on pilots and making it easier for the Mustangs to provide escort. The Mustangs were employed not only as escorts, hugging the bomber formation as had the German Me 109s in the Battle of Britain, but as fighting patrols whose role was to seek out and destroy the enemy.
The B-17Es and B-17Fs became used extensively by the 8th Air Force in Europe, but in two major operations against German strategic targets, on 17 August and 14 October 1943, a total of 120 aircraft were lost. Clearly the Fortresses could not mount an adequate defence, no matter how cleverly devised was the box formation in which they flew. The hard truth was that without adequate long-range fighter escort they were very vulnerable to attack during mass daylight operations. Many of the losses were attributed to head-on attack, and the final major production version was planned to offset this shortcoming.
Thus the B-17Gs had a ‘chin’ turret housing two 12.7 mm (0.50 in) machine guns mounted beneath the fuselage nose, which meant that this version carried a total of thirteen 12.7 mm (0.50 in) guns. To increase the aircraft’s operational ceiling, later production examples had an improved turbocharger for their R-1820-97 engines. B-17G production totalled 8,680, built by Boeing (4,035), Douglas (2,395), and Lockheed Vega (2,250).
A combat wing, dubbed a Pulk (herd) by the Luftwaffe, deployed formidable defensive power and was a daunting sight to novice fighter pilots. The B-17G’s defensive armament consisted of thirteen .50 machine guns. A combat wing could bring to bear 648 machine guns firing 14 rounds a second with an effective range of 600 yards (548 m). The two-ounce bullets remained lethal on the human body at ranges of up to 4 miles (6.5 km).
“… the progressive destruction of and dislocation of the German military, industrial and economic system, and the undermining of the morale of the German people to a point where their capacity for armed resistance is fatally weakened.”
Although used most extensively in Europe and the Middle East, B-17s were operational in every area where US forces were fighting. In the Pacific theatre they offered invaluable service for maritime patrol, reconnaissance, and conventional and close-support bombing. A number of variants were also produced or converted for special purposes and operations, and details of these follow. Although almost 13,000 B-17s were built, only a few hundred B-17Gs were retained in USAAF service after the end of the war, and these were soon made redundant.
Engines: Four 1,200-hp Wright R-1820-97 Cyclone turbocharged radial piston engines
Weight: Empty 36,135 lbs., Max Takeoff 65,500 lbs.
Wing Span: 103ft. 9in.
Length: 74ft. 4in.
Height: 19ft. 1in.
Maximum Speed at 25,000 ft: 287 mph
Cruising Speed: 182 mph
Ceiling: 35,800 ft.
Range: 2,000 miles with 6,000 lb. bomb load
13 12.7-mm (0.5-inch) machine guns
Up to 17,600 pounds of bombs
Number Built: ~12, 800+