Defeat of the Luftwaffe
The following article is drawn from our latest book The Bomber Offensive and discusses innovations in fighter tactics and technology that eventually brought about the defeat of the Luftwaffe. You can download the full book in PDF or on Amazon Kindle. The full book and accompanying interactive materials are also available to all our members as part of the larger European Air War online course. Click the button below to learn more about the full book and online course.
As the British struggled for control of the night sky, the USAAF was working hard to develop a solution to the survivability problem after the disaster of “Black Thursday” in October of 1943. With the failure of the self-defending bomber concept, the next option was to extend the range of fighter escort so that fighters could protect the bombers all the way to the target and back, even if the target was deep inside Germany. As mentioned earlier, fighters could extend their range by carrying external fuel tanks but early in the war, most tanks were not designed for combat and reduced a fighter’s combat performance.
What was needed was an external fuel tank that was pressurized so it would still feed the engine at high altitude where the bombers flew. In addition, the pilot should be able to jettison the tank(s) quickly and easily upon making contact with the enemy since the added weight and drag of the tank(s) would greatly reduce the aircraft’s combat performance. The pilot would ensure the engine drew fuel from the drop tank(s) first for as long as possible, saving the internal fuel for the return legs of the mission.
The design of drop tanks had been evolving slowly since around the time of the first Schweinfurt raid in August of 1943. The first tank fielded was the relatively small 75-gallon drop tank which only slightly improved the range of the P-47, the main USAAF fighter operating in Europe at the time. The following month in September of 1943 the British fielded the new 108-gallon tank, a brilliant design fashioned from specially treated paper. Not only were the paper tanks light and cheap, but jettisoned tanks would burst after hitting the ground, preventing the Germans from salvaging any remaining fuel. The P-47 was also later modified to be able to carry a tank (either 75-gallon or 108-gallon) under each wing, as opposed to only one on the centerline.
These sequential innovations slowly extended the range of USAAF escort fighters for the remainder of 1943. However, as evidenced by the disastrously high losses in October of 1943, the evolution and range of escort fighters was not progressing quickly enough to adequately protect the bomber force. The continued rise in casualties also suggested that maybe escort range was not the only factor that needed to evolve in order to change the balance of the competition.
It was not until January of 1944, right in the midst of the costly RAF campaign over Berlin, that the USAAF began to significantly change the survivability equation. During this time, General James “Jimmy” Doolittle replaced Ira C. Eaker as the commander of the 8th Air Force on 6 January 1944. While Doolittle’s arrival, leadership and reforms certainly contributed to the 8th’s improved performance, it would be unfair not to credit Eaker for doing an outstanding job building the organization into an effective fighting force.
Early in the war, when the USAAF Commander, Henry “Hap” Arnold had to choose someone to design and build America’s bomber force, perhaps the most complex task facing the fledgling air arm, Eaker was a logical choice. Eaker was a superb administrator and skilled pilot with an extensive technical knowledge of aviation and air combat. He commanded the 8th Air Force since its inception and shepherded it through the most difficult and complex phases of its growth and evolution. However, by the end of 1943 the Allied leadership, including Arnold, was growing frustrated with the 8th Air Force’s lack of results and mounting casualties. New leadership might reverse these disturbing trends.
Arnold chose James “Jimmy” Doolittle to replace Eaker as commander of the 8th Air Force. Doolittle was a bold and aggressive officer, world-renowned for personally leading a formation of sixteen B-25s on the daring 18 April 1942 Tokyo raid. Eaker would be transferred to command all Allied air forces in the Mediterranean theater. While technically a promotion, Eaker objected fervently to the change but to no avail. Arnold had made his decision.
Beginning in January 1944, under Doolittle’s command, the 8th Air Force would implement two key tactical innovations that would arguably make the most significant contribution to the future success of the Combined Bomber Offensive. The first of these changes was the implementation of “phased escort,” a concept that had been in development for months but was just now being implemented. The second was Doolittle’s bold but also controversial decision to abandon close escort tactics, a decision that potentially put bombers at even greater risk.
The phased escort concept had been in development for some time and the USAAF first began to implement the new tactics on 7 January 1944, the day after Doolittle took over. Given that he had only been in command for one day, Doolittle himself was not responsible for the planning or implementation of phased escort but the new procedure greatly complimented the innovations and changes Doolittle would introduce in the following months. In simple terms, phased escort involved having different groups of fighters escort a single bomber formation in successive “phases” which greatly increased the total range that the escorts could reach.
Prior to the switch to phased escort, fighters would rendezvous with the bombers before entering enemy territory and remain with the bombers for as long as possible until the fighters had to return to base because of low fuel. This approach was not fuel efficient for the fighters. First, it took time for the fighters to rendezvous with the bombers and in some cases the fighters had to wait for the bombers to arrive. This burned fuel. Second, because the most fuel-efficient cruising speed for fighters was faster than the bombers could fly, fighters had to slow down and/or fly in S-turns in order to keep pace with the bombers. This greatly reduced the fighters’ total range.
The phased escort would have one group of fighters escort the bombers for the first phase of the mission, but another group would fly to a second rendezvous point further along the mission route. This second group could achieve better fuel efficiency prior to joining the bombers by flying in a straight line and could thus achieve greater overall range. Employing multiple groups of fighters in this way, each one responsible for a different phase of the mission, proved to be one of the most effective survivability innovations of the European Air War.
The second innovation that was potentially even more decisive was Doolittle’s decision to abandon close escort tactics. Up until the time Doolittle took over, fighter aircraft were directed to stay close to the bomber formations to protect them. The fighters were not allowed to break formation in order to offensively pursue and shoot down enemy fighters. The logic behind this approach made sense given the rising and ultimately unsustainable losses the bombers were suffering. Therefore, the primary mission of 8th Air Force fighters was to protect the bombers and their crews in order to sustain the air offensive.
While it may have appeared logical on the surface, this essentially defensive approach gave the Luftwaffe the advantage in two key respects. First, it allowed the Germans to decide the time and place of battle and to refuse battle if the odds were not in their favor. If Luftwaffe fighters approached a bomber formation that was heavily defended by Allied fighters, they could simply turn away and pick a time or place where bombers were more vulnerable. Second, when the fighters did attack, they had plenty of time to get into the most advantageous formation and position for battle. Thus, while the defensive approach seemed to increase survivability for the bombers, it actually had the opposite effect in the long term since it did nothing to eliminate the source of the threat.
By cutting the American fighters loose, Doolittle allowed them to target and eliminate the threat at its source. U.S. fighters could aggressively pursue and destroy the enemy when he was most vulnerable. The primary objective was not to protect the friendly bombers but rather to destroy the enemy fighters so they could not survive to attack again on another day. While some bomber crews resented this change and felt it put them at greater risk, it was ultimately this transition from a defensive approach to an offensive approach that allowed the USAAF to attrit and destroy the Luftwaffe fighter force.
The concerns of the bomber crews were not unfounded since bomber loss rates persisted and in some cases even increased despite the introduction of the new escort technologies and tactics. In fact, the USAAF lost more aircraft in April of 1944 than any other month of the war. This was well after the introduction of long-range escorts. Therefore, the popular conception that the introduction of long-range fighters was decisive because it finally allowed escorts to protect bombers all the way to the target is ill-founded. The USAAF intensified attacks, and losses continued to mount on both sides of the battle. However, while the Allies could sustain these casualties the Luftwaffe could not.
Thus, aligned with Doolittle’s intent, the most critical contribution of the long-range escorts and new tactics was not was not protecting the bombers but rather shooting down more German fighters. On 20 February 1944, the USAAF and RAF kicked off “Big Week,” a coordinated string of bombing raids designed to draw the Luftwaffe into a massive and decisive air battle. Big Week and subsequent raids in the coming months achieved the desired effect. By May of 1944, the American fighters had almost completely swept the opposition from the skies and more than ever before, the Allies had found a solution to the bomber survivability problem.
In combination with these tactical evolutions and the improvement in drop tank technology, a third innovation greatly contributed to the USAAF success in improving bomber survivability, the deployment of the North American P-51 Mustang. The Mustang was one of the best fighters of the war but in particular, it had better range than any of its counterparts at the time. When combined with new drop tanks and phased escort, the Mustang allowed fighter escort to accompany bombers deeper into enemy territory than ever before. The introduction of the longer-range Mustang also fit nicely with the phased escort concept since the shorter-range fighters could cover the first phases of a mission and leave the deeper phase to the Mustangs.
Another characteristic of the Mustang that made a great contribution to Allied success was its low cost. One of the most widely accepted historical explanations for why the Allies won the air war in Europe relates their superior capability to produce aircraft and train pilots. U.S. industrial capacity expanded dramatically throughout the war, totally eclipsing the capabilities of all other belligerents. Thus, the Allies could sustain losses and replace them while the Germans could not and while the air battles of 1943-44 were costly to both sides, losses would prove far more crippling and irreversible for the Germans. The low cost of the Mustang contributed to this imbalance by further increasing the Allied ability to produce and deploy large numbers of fighters. Combined with the crippling attrition caused by Doolittle’s new offensive approach to fighter combat, this rapid production served to completely tip the scales in the Allies favor.
We hope you enjoyed this short article on the Defeat of the Luftwaffe. This article is drawn from our interactive online course on the European Air War and the companion book “The Bomber Offensive.” You can download the full book in PDF or on Amazon Kindle. Click the button below to learn more about the full book and online course.
