Schweinfurt–Regensburg mission

The Schweinfurt–Regensburg mission was an air combat battle in World War II. A strategic bombing attack flown by B-17 Flying Fortresses of the U.S. Army Air Forces on August 17, 1943, it was conceived as an ambitious plan to cripple the German aircraft industry. The mission was also known as the "double-strike mission" because it entailed two large forces of bombers attacking separate targets in order to disperse fighter reaction by the Luftwaffe, and was the first "shuttle" mission, in which all or part of a mission landed at a different field and later bombed another target returning to its base.

After being postponed several times by unfavorable weather, the operation, known within the Eighth Air Force as "Mission No. 84", was flown on the anniversary of the first daylight raid by the Eighth Air Force. Mission No. 1 had only been a shallow penetration of France by 12 bombers of a single bombardment group well-protected by escort fighters to attack the Rouen-Sotteville railroad yard. Mission No. 84 marked the anniversary with a strike by 376 bombers of sixteen bomb groups against German heavy industry well beyond the range of escorting fighters.

The mission inflicted heavy damage on the Regensburg target, but at catastrophic loss to the force, with 60 bombers lost and many more damaged beyond economical repair. As a result, the Eighth Air Force was unable to follow up immediately with a second attack that might have seriously crippled German industry. When Schweinfurt was finally attacked again two months later, the lack of long-range fighter escort had still not been addressed and losses were even higher. As a consequence, deep penetration strategic bombing was curtailed for five months.

As soon as the reconnaissance photographs were received on the evening of the 17th, Generals Eaker and Anderson knew that the Schweinfurt raid had been a failure. The excellent results at Regensburg were small consolation for the loss of 60 B-17s. The results of the bombing were exaggerated, and the high losses were well disguised in after-mission reports. Everyone who flew the mission stressed the importance of the escorts in reducing losses; the planners grasped only that Schweinfurt would have to be bombed again, soon, in another deep-penetration, unescorted mission

The mission plan
Because of diversions of groups to the invasion of North Africa, the bomber force in England had been limited in size to four groups of B-17s and two of B-24's until May 1943. At that time, and in conjunction with the Pointblank Directive to destroy the Luftwaffe in preparation for Operation Overlord, the B-17 force had expanded fourfold and was organized into the 1st and 4th Bombardment Wings (which due to their large size would soon be re-designated Bomb Divisions). The 1st Bombardment Wing, which included all of the original B-17 groups, was based in the English Midlands while the 4th Bombardment Wing stations were located in East Anglia.

Pointblank operations in April and July 1943 had concentrated solely on the production of the Fw 190 at factories in Bremen, Kassel, and Oschersleben, and although serious losses to the bomber forces had occurred, the attacks had been successful enough to warrant attacking those manufacturing Messerschmitt Bf 109s.

The production of Bf 109s (and almost half of all German fighters) was located in Regensburg and in Wiener Neustadt, Austria. To attack these in sufficient force, "Operation Juggler" was conceived, in which the fighter production plants in Wiener Neustadt were targeted for attack by B-24 Liberators of the Ninth Air Force based in Libya, and Regensburg by B-17s of the Eighth Air Force. The original mission date of August 7 could not be met because of bad weather, and the B-24s flew Operation Juggler on August 13 without participation by the Eighth Air Force, which was still hampered by unacceptable weather conditions.

To successfully complete its portion of the attack, the Eighth Air Force decided to attack a target in central Germany as well as Regensburg to divide and confuse German air defenses. The 4th Bombardment Wing, using B-17s equipped with "Tokyo (fuel) tanks" for longer range, would attack the Messerschmitt Bf 109 plants in Regensburg and then fly on to bases in Bône, Berteaux and Telergma (French Algeria). The 1st Bombardment Wing, following it, would turn northeast and bomb the ball-bearing factories of Schweinfurt (where almost the entire production of bearings was centralized) and by doing so catch German fighter aircraft on the ground re-arming and refueling. Because of limited range thanks to (inexplicably) not employing drop tanks, escorting P-47 Thunderbolt fighters would be able to protect the bombers only as far as Eupen, Belgium, which was roughly an hour's flying time from both of the targets.

Two supporting attacks were also made a part of the overall mission plan. The first, a diversionary attack, involved the bombing of three locations along the French and Dutch coast: the German airfields at Bryas-Sud and Marck by American B-26 Marauder and Royal Air Force Mitchell medium bombers, and the marshalling yards at Dunkirk by other Mitchells, all timed to coincide with the Regensburg strike.

The second was a series of attacks on Luftwaffe fighter fields at Poix, Lille-Vendeville, and Woensdrecht by Hawker Typhoons of the RAF simultaneous with the diversionary attack, and Poix by two groups of B-26s in the afternoon as the Schweinfurt force was returning.

Weather delays
Eighth Air Force bomber operations were calculated with one to two hours of climb and assembly into formations factored into mission lengths. In addition the mission length for the Regensburg force was anticipated to be of eleven hours' duration, so that commanders had only a 90-minute "window" in which to launch the mission and still allow the 4th Bombardment Wing B-17s to reach North Africa in daylight. Mission 84 planning indicated a takeoff window from dawn (approximately 06:30 British Double Summer Time) to approximately 08:00 without cancelling the mission.

At dawn of August 17, after airmen had gone to their airplanes, England was covered in fog. The mission takeoff was delayed until 08:00, when the fog had cleared sufficiently over East Anglia to allow the 4th Bombardment Wing to take off using instruments, a technique they had practiced. Although attacking both targets simultaneously was deemed critical to success of the mission without prohibitive loss, the Regensburg force was ordered to take off, even though the 1st Bombardment Wing remained grounded at its bases by the adverse weather. By the time the fog had sufficiently cleared over the Midlands, the Regensburg force had already reached the coast of the Netherlands, which indicated that reacting German fighters would have sufficient time to land, replenish, and attack the second task force. Consequently the launch of the Schweinfurt force was further delayed to allow U.S. escort fighters sufficient time to return to base to rearm for a second escort mission. In all the 1st Wing was delayed more than three hours behind the 4th Wing.

Regensburg strike force
The Regensburg task force was led by the 4th Bombardment Wing commander, Colonel Curtis E. LeMay. It consisted of seven B-17 Groups totalling 146 aircraft, each group but one flying a 21-aircraft combat box tactical formation. The groups were organized into three larger formations termed "provisional combat wings", three groups in a Vee formation wing box leading the procession, followed in trail by two wing boxes of two groups each in echelon formation with one group leading and the second trailing at lower altitude.


 * SOURCE: Decision Over Schweinfurt, Mighty Eighth War Diary

Approximately fifteen minutes after it crossed the coast at 10:00, the Regensburg force encountered the first German fighter interception, which continued with growing intensity nearly all the way to the target area. Several factors weighed against the Regensburg force in this air battle. The arrangement of two groups instead of three in the two following provisional wings meant a third fewer guns available to each for their mutual defense and made them more likely targets. The overall length of the task force was too great for effective fighter support. The last wing formation of bombers was fifteen miles behind the first and nearly out of visual range. Of the two groups of P-47s (87 aircraft) tasked to escort the force to the German border, only one arrived at the rendezvous point on time, covering only the lead wing, and the second arrived fifteen minutes late. Finally, both P-47 groups were forced to turn back to base after only fifteen minutes of escort duty, without engaging any German interceptors. The last provisional wing in the task force was left without any fighter protection at all.

After ninety minutes of combat the German fighter force broke off the engagement, low on fuel and ammunition. By then at least 15 bombers had been shot down or fatally damaged, 13 from the trailing formation. However anti-aircraft fire ("flak") was light over Regensburg and visibility clear, and of the remaining 131 bombers, 126 dropped 298.75 tons of bombs on the fighter aircraft factories with a high degree of accuracy at 11:43 British time.

The Regensburg force then turned south to cross the Alps, confronted by only a few twin-engined fighters soon forced to disengage by lack of range. The German force had not been prepared for this contingency, but they were also in the process of re-arming to meet the Schweinfurt force, then forming over East Anglia. Even so, two damaged B-17s turned away from the Regensburg task force and landed in neutral Switzerland, where their crews were interned and the bombers confiscated. Another crash-landed in Italy and five more were forced down by lack of fuel into the Mediterranean Sea. In all 24 bombers were lost and more than 60 of the 122 survivors landing in Tunisia had suffered battle damage.

Schweinfurt strike force
The 1st Bombardment Wing, commanded by Brigadier General Robert B. Williams, was made up of nine B-17 groups administratively organized into three combat wings. In a "maximum effort", however, it had a sufficient number of aircraft and trained crews to make four wing boxes. This was accomplished by eight of the nine groups providing a squadron or spare aircraft to form three "composite groups" created for this mission, distributing them among the others to form a fourth wing box. (This concept, used by the Eighth Air Force several times before, was possible because normally only three of a group's four squadrons were scheduled on any given mission.)

While individual group boxes were not as large as usual, the total force counted 230 bombers. The Schweinfurt force was divided into two task forces of two wings (six groups) each and was more than twenty miles long. Gen. Williams personally led the mission, flying as co-pilot in an aircraft of the lead formation, as wingman to the commander of the 91st Bomb Group.


 * SOURCE: Decision Over Schweinfurt

The Schweinfurt task forces followed the same route as the Regensburg force. Because of the delayed start of the mission, eight squadrons of RAF Spitfire fighters (96 aircraft) from 11 Group and 83 Group had been added to escort the Schweinfurt force as far as Antwerp, where P-47s would take over and escort it to Eupen. The field order for the mission specified that the B-17s would fly at altitudes between 23,000 and 26,500 feet (7,000-8,000 m), but approaching the coast of the Netherlands at 13:30, it was confronted with developing cloud masses not present earlier in the day. The commander of the first task force estimated that the bombers would not be able to climb over the clouds and elected to fly under them at 17,000 feet (5,000 m), increasing the vulnerability of the bombers to fighter attacks.

The first German attacks began almost immediately and employed different tactics from the morning mission. The lead wing was attacked continuously in head-on attacks by both Messerschmitt Bf 109 and Fw 190 fighters, and although the RAF escorts claimed eight victories they were forced to return to base early in the engagement. The two groups of P-47s (88 aircraft) arrived five and eight minutes late, and despite some individual combats, they too were forced to break off virtually as soon as they arrived.

Inside German airspace, the Bf 109 G-6 fighters of 5 Staffel / JG 11, which had pioneered the fitment of the Werfer-Granate 21 unguided air-to-air rocket weapon system to the Luftwaffe's single engine day fighter force the previous day, as well as the similarly armed rocket-launching twin-engined Bf 110 Zerstörer heavy fighters, including night fighters, joined the battle as more than 300 fighters from 24 bases opposed the raid. At 14:36 the force diverged from the morning's route at Worms, Germany, alerting the German defenders that the target was Schweinfurt. Losses among the 57 B-17's of the lead wing were so severe that many among its airmen considered the possibility that the wing might be annihilated before reaching the target. However fifteen miles from Schweinfurt the opposing fighters, after shooting down 22 bombers, disengaged and landed to refuel and re-arm in order to attack the force on its way out. Five miles from Schweinfurt German anti-aircraft guns began firing an effective flak barrage into the path of the bomber force.

At 14:57 approximately 40 B-17s remained of the lead wing when it dropped its bombs on the target area containing five factories and 30,000 workers, followed over a 24-minute span by the remainder of the force. Each wing found increasingly heavy smoke from preceding bomb explosions a hindrance to accuracy. 183 bombers dropped 424.3 tons of bombs, including 125 tons of incendiary bombs.

Three B-17s were shot down by flak over Schweinfurt. Fifteen minutes after leaving the target each task force circled over the town of Meiningen to reassemble its formations, then continued west toward Brussels. At approximately 15:30 German fighters renewed their attacks, concentrating now on damaged bombers. Between 16:20 and 17:00 a covering force of 93 P-47s and 95 Spitfires arrived to provide withdrawal support, claiming 21 fighters shot down, but eight more bombers were lost before the force reached the North Sea, where three more crash-landed. The Schweinfurt force lost a total of 36 bombers.


 * SOURCE: Decision Over Schweinfurt, Mighty Eighth War Diary

Results and losses
55 bombers with 552 crewmen were listed as missing as a result of the August 17 double-target mission. Approximately half of those became prisoners-of-war, and twenty were interned. 60 aircraft were lost over German-controlled territory, in Switzerland, or ditched at sea, with five crews rescued. Seven aircrew were killed aboard bombers safely returning to base, and 21 wounded.

The 60 aircraft lost on a single mission more than doubled the highest previous loss at that time. There were also 55-95 additional aircraft badly damaged. Of those damaged, many were stranded in and never repaired. Three P-47 Thunderbolts of the 56th Fighter Group and two RAF Spitfires were shot down attempting to protect the Schweinfurt force.

Spitfire pilots claimed 13 German fighters shot down and P-47 pilots claimed 19. Gunners on the bombers claimed 288 fighters shot down, but Luftwaffe records showed only 25-27 were lost.

In Regensburg all six main workshops of the Messerschmitt factory were destroyed or severely damaged, as were many supporting structures including the final assembly shop. In Schweinfurt the destruction was less severe but still extensive. The two largest factories, Kugelfischer & Company and Vereinigte Kugellager Fabrik I, suffered 80 direct hits. 35,000 m² (380,000 square feet) of buildings in the five factories were destroyed, and more than 100,000 m² (1,000,000 square feet) suffered fire damage. All the factories except Kugelfischer had extensive fire damage to machinery when incendiaries ignited the machine oil used in the manufacturing process.

Albert Speer reported an immediate 34 per cent loss of production, but both the production shortfall and the actual loss of bearings were made up for by extensive surpluses found throughout Germany in the aftermath of the raid. The industry's infrastructure, while vulnerable to a sustained campaign, was not vulnerable to destruction by a single raid. Speer indicated that the two major flaws made by the USAAF in the August strike were first in dividing their force instead of all striking the ball-bearing plants, and second, failing to follow up the first strike with repeated attacks.

203 civilians were also killed in the strike.

The Schweinfurt mission in particular foretold the failure of deep penetration raids of Germany without adequate long-range escort. The 1st Bomb Wing was over German-occupied territory for three hours and thirty minutes, of which two hours and ten minutes, including all of the time spent over Germany itself, saw no fighter support whatsoever. When the second attack on Schweinfurt came on October 14, the loss of more than 20% of the attacking force (60 out of 291 B-17s) resulted in the suspension of deep raids for five months.

This mission was enshrined in fiction as the 'Hambrucken raid' in Beirne Lay and Sy Bartlett's novel, Twelve O'Clock High. It provides a reasonably accurate view of the thinking behind the planners' intention and the decisions that led to the abandonment of the goal of launching a double strike in such a way that the second strike would meet no aerial opposition; and of the action in the air itself. The Schweinfurt portion of the mission also formed the framework for the novel The War Lover, by John Hersey. In the early 1990s, the raid was depicted for the first time in a video game, as a playable mission in Secret Weapons of the Luftwaffe.