THE FORTY-FOURTH HARMON MEMORIAL LECTURE IN MILITARY HISTORY The Aircraft that Decided World War II: Aeronautical Engineering and Grand Strategy, 1933-1945, The American Dimension John F. Guilmartin, Jr. United States Air Force Academy 2001 The Aircraft that Decided World War II: Aeronautical Engineering and Grand Strategy, 1933-1945, The American Dimension John F. Guilmartin, Jr. The Ohio State University THE HARMON MEMORIAL LECTURES IN MILITARY HISTORY NUMBER FORTY-FOUR United States Air Force Academy Colorado 2001 THE HARMON LECTURES IN MILITARY HISTORY The oldest and most prestigious lecture series at the Air Force Academy, the Harmon Memorial Lectures in Military History originated with Lieutenant General Hubert R. Harmon, the Academy's first superintendent (1954-1956) and a serious student of military history. General Harmon believed that history should play a vital role in the new Air Force Academy curriculum. Meeting with the History Department on one occasion, he described General George S. Patton, Jr.'s visit to the West Point library before departing for the North African campaign. In a flurry of activity Patton and the librarians combed the West Point holdings for historical works that might be useful to him in the coming months. Impressed by Patton's regard for history and personally convinced of history's great value, General Harmon believed that cadets should study the subject during each of their four years at the Academy. General Harmon fell ill with cancer soon after launching the Air Force Academy at Lowry Air Force Base in Denver in 1954. He died in February 1957. He had completed a monumental task over the preceding decade as the chief planner for the new service academy and as its first superintendent. Because of his leadership and the tensions of the cold war, Congress strongly supported the development of a first-rate school and allotted generous appropriations to build and staff the institution. The Academy's leadership felt greatly indebted to General Harmon and sought to honor his accomplishments in some way. The Department of History considered launching a lecture series to commemorate his efforts, and in 1959 the Harmon Memorial Lecture Series in Military History was born. The Harmon Lecture series supports two goals: to encourage the interest in contemporary military history and to stimulate in cadets a lifelong interest in the study of the history of the military profession. The lectures are published and distributed to interested individuals and organizations throughout the world and many are used in courses at the Academy. In this way, we continue to honor the memory of General Harmon, who during his lifetime developed a keen interest in military history and greatly contributed to establishing the United States Air Force Academy. LIEUTENANT GENERAL HUBERT REILLY HARMON Lieutenant General Hubert R. Harmon was one of several distinguished Army officers to come from the Harmon family. His father graduated from the United States Military Academy in 1880 and later served as Commandant of Cadets at the Pennsylvania Military Academy. Two older brothers, Kenneth and Millard, were members of the West Point class of 1910 and 1912, respectively. The former served as Chief of the San Francisco Ordnance District during World War II; the latter reached flag rank and was lost over the Pacific during World War II while serving as Commander of the Pacific Area Army Air Forces. Hubert Harmon, born on April 3, 1882, in Chester, Pennsylvania, followed in their footsteps and graduated from the United States Military Academy in 1915. Dwight D. Eisenhower also graduated in this class, and nearly forty years later the two worked together to create the new United States Air Force Academy. Harmon left West Point with a commission in the Coast Artillery Corps, but he was able to enter the new Army air branch the following year. He won his pilot's wings in 1917 at the Army flying school in San Diego. After several training assignments, he went to France in September 1918 as a pursuit pilot. Between World Wars I and II, Harmon, who was a Major during most of this time, was among that small group of Army air officers who urged Americans to develop a modern, strong air arm. At the outbreak of World War II, Brigadier General Hubert Harmon was commanding the Gulf Coast Training Center at Randolph Field, Texas. In late 1942 he became a Major General and head of the 6th Air Force in the Caribbean. The following year General Harmon was appointed Deputy Commander for Air in the South Pacific under General Douglas MacArthur, and in January 1944 he assumed command of the 13th Air Force fighting in that theater. After the war General Harmon held several top positions with the Air Force and was promoted to Lieutenant General in 1948. In December 1949 the Air Force established the Office of Special Assistant for Air Force Academy Matters and appointed General Harmon its head. For more than four years Harmon directed all efforts at securing legislative approval for a U.S. Air Force Academy, planned its building and operation, and served on two commissions that finally selected Colorado Springs, Colorado, as the site for the new institution. On August 14, 1954, he was appointed first Superintendent of the Air Force Academy. Upon General Harmon's retirement on July 31, 1956, the Secretary of the Air Force presented him with his third Distinguished Service Medal for his work in planning and launching the new service academy and setting its high standards. In a moving, informal talk to the cadets before leaving the Academy, General Harmon told the young airmen that the most important requirements for success in their military careers are integrity and loyalty to subordinates and superiors. "Take your duties seriously, but not yourself," he told the cadets. General Harmon passed away on February 22, 1957, just a few months before his son Kendrick graduated from West Point. The general's ashes were interred at the Air Force Academy's cemetery on September 2, 1958. On May 31, 1959, the Academy's new administration building was named Harmon Hall in his memory. JOHN F. GUILMARTIN, JR. John F. Guilmartin, Jr., is professor of military history at Ohio State University, Columbus. He is also a Vietnam War veteran, having flown over 120 combat missions. He attended the United States Air Force Academy, earning a commission as a 2nd Lieutenant and graduating with a B.S. in 1962. He trained as a helicopter pilot at Stead AFB, Nevada, and went to Thailand in 1965 with the Aerospace Rescue and Recovery Service. He flew missions in Thailand, Laos and North Vietnam and was awarded two Silver Stars. In 1966 he returned to the United States and after a year as an instructor pilot at the Rescue Combat Crew Training School, received an AFTI assignment to Princeton University where he received his Master's and Doctorate degrees in 1969 and 1971, respectively. His first book, Gunpowder and Galleys, is derived from his dissertation. After receiving his Ph.D., Dr. Guilmartin returned to the Air Force Academy to teach history. In 1975 he volunteered for a second tour in Southeast Asia and participated in the evacuation of Saigon. His unit also flew in the operations involved in the Mayaguez incident; in 1995 he recorded their heroism in A Very Short War. Following the Vietnam War, Lt. Col. Guilmartin served in the Rescue Headquarters tactics shop from 1978-79. He then became the editor of the Air University Review, the professional journal of the U.S. Air Force, and retired from the service in 1983. He taught at Rice University and the Naval War College before coming to Ohio State. Professor Guilmartin is an authority on military history, maritime history, and the history of technology. He is an early modern Europeanist whose research focuses primarily on the sixteenth and seventeenth centuries. He also is interested in aerospace history and has written about the Vietnam War and the Gulf War. He has also written America in Vietnam: The Fifteen Year War in 1991, and Galleons and Galleys in 2002. The Aircraft that Decided World War II: Aeronautical Engineering and Grand Strategy, 1933-1945, The American Dimension The purpose of this essay is to connect, from an American perspective, two propositions: that air power was critical to the conduct and outcome of the Second World War, and that aircraft design contributed the crucial role in the process. There is nothing controversial about the first proposition. Historians and theoreticians may debate the decisiveness of strategic bombing, but few would deny the decisiveness of air power in the generic sense, if for no other reason because control of the air invariably provided an essential ingredient of victory in the battles and campaigns comprising World War II and whose cumulative effects of airpower determined its flow and eventual outcome. Indeed, the war’s only campaign of major strategic consequence won without benefit of air superiority was the US Navy’s submarine campaign against Japanese shipping, a fact that is in part testimony to Japanese weakness in the air.1 To underline air power’s importance, consider the battles and campaigns principally responsible for shaping the course of the conflict: the Battle of France, the Battle of Britain, the early German victories on the Eastern Front; the Japanese Centrifugal Offensive; Midway; Guadalcanal; Stalingrad; El Alamein; the Tunisian campaign; the Battle of the Atlantic; D-Day; the Normandy campaign, breakout and pursuit; the Destruction of Army Group Center; the New Guinea campaign; the Central Pacific campaign culminating in the Battle of the Philippine Sea and the seizure of the Marianas; the Battle of Leyte Gulf; and the bombing of Japan. In every case, victory was secured from the air, was dependent upon its control, or both.2 Extending our analysis to smaller engagements of strategic consequence yields a number of naval actions in which air power played a negligible role. Significantly, most were fought at night, testimony to the vulnerability of warships to daylight air attack even early in the war.3 Notable among them were a series of night surface engagements between Japanese and American forces during the Guadalcanal campaign.4 These engagements took place at night precisely because the Japanese Navy sought cover of darkness to negate US airpower. Note, too, that aerial reconnaissance (or the failure thereof) played a major role in most if not all of these engagements and that American superiority in the air was essential to Allied victory in the overall campaign.5 The other exceptions are partial and qualified. The Royal Navy was able to fight convoys through to Malta and Murmansk under heavy air assault and with little or no air cover, but at great cost. Indeed, Japanese successes in the Guadalcanal campaign aside, the only naval victory of consequence won by surface forces unaided by air and fought within range of enemy air fields was the 26 December 1943 Battle of North Cape in which the Royal Navy sunk the German battle cruiser Scharnhorst: confined to its Norwegian airfields by abominable weather, the Luftwaffe failed to intervene.6 We should also note that a number of the war's most important campaigns were fought entirely in the air, notably the Battle of Britain, the Combined Bomber Offensive, and the strategic bombing campaign of Japan. I would argue that all three were strategically decisive, an assertion that raises the question of strategic bombing’s effectiveness in World War II. I will address that question later, but first let me make a fundamental point: that war in the air is inherently different from other forms of warfare and that we do not truly understand it, even today, over a half century after VJ Day. A key problem is that we approach strategic bombing with the implicit assumption that air campaigns and battles can be judged using the vocabulary, criteria for success or failure, and analytical framework used to evaluate warfare on land and at sea. I contend that the appropriate criteria for judging strategic air campaigns, at least, are quite different and that in consequence the results of the debate so far are of dubious validity. As evidence of our incomplete understanding of the nature of aerial warfare, consider the general lack of consensus—or even awareness—of what constitutes an air campaign. To illustrate the point, consider the last major Axis campaign victory of World War II. When asked to name the campaign in question, most draw a momentary blank and then think of the Battle of the Bulge before recalling that it ended in German defeat. It was, in fact, the Battle of Berlin, the effort by Royal Air Force Bomber Command between November 1943 and March 1944 to destroy Berlin repeating Hamburg's destruction the previous summer.7 In the process, the British inflicted considerable damage on Germany to be sure, but the result was unequivocally a German victory: Bomber Command called off its offensive after an accumulative loss of nearly eleven hundred aircraft, almost all of them four-engine bombers.8 Indeed, the final battle of the campaign, the 30 March Nuremberg raid, was one of the largest air battles of the war, if not the largest,9 and a signal German victory. There is no denying the strategic importance of the British defeat in terms of expenditure of resources and in lives lost, a cost made all the more painful by the fact that the lives in question were those of a highly-trained and strategically important elite aircrews, yet it was not a typical battle or campaign. To expand on the point, consider the nature of the Combined Bomber Offensive. We ordinarily think of it as a campaign, but it was in fact something larger, for it contained within it operations that clearly qualify as campaigns in their own right: RAF Bomber Command’s area bombing of German cities; the United States Army Air Forces' Unescorted Daylight Strategic Bombardment Campaign of 1943; the 1944 campaign against German sources of oil and fuel production; and Big Week, the USAAF effort in February 1944 that forced the Luftwaffe fighter force to accept battle and, ultimately, defeat. The lesson is evident. Not only does the terminology that we have inherited from land and naval warfare fit war in the air poorly, it carries with it analytical baggage that distorts analysis. To further underline the inherent difference between war in the air and war on the surface, one can argue—and I do—that World War II in the air comprised a unitary global conflict in ways that the war on land and at sea did not. On land and at sea, the war can be usefully divided into theaters and fronts: the European Theater; the Eastern Front; and the Mediterranean, China-Burma-India, Southwest Pacific, and Central Pacific theaters, and so on. By and large, there was little movement of ground forces from one to another. With the partial exception of the Germans, who used interior lines to transfer their strategic reserves, once ground forces were committed to a theater or front they stayed there. The same general point applies to naval forces to an only slightly lesser degree. But what about air forces? Air forces were transferred from theater to theater with some frequency. The USAAF transferred much of its deployed force structure from Britain to North Africa in the autumn of 1942. The Germans shifted air units from front to front far more frequently than their ground reserves. The Japanese Army Air Force transferred much of its strength from the Home Islands and Manchuria to the Southwest Pacific in 1942-43. The manner in which air reserves were deployed in certain critical instances leads me to the conclusion that at least senior Allied leaders implicitly understood that the air war was indivisible by theater. Let me make the point by example. For the US Navy, the series of actions in May and June of 1942 that culminated in the Battle of Midway were the most critical of the war, a fact of which senior commanders were keenly aware well before the fact. As they were also keenly aware, fleet carriers were the critical operational asset. At the beginning of May 1942, the US Navy had five fleet carriers capable of flight operations: Lexington, Enterprise, Hornet, Yorktown and Wasp.10 Of these, Lexington was sunk at the Coral Sea and Enterprise, Hornet and Yorktown fought at Midway. Where was Wasp? More precisely, why was Wasp not at Midway? Because she was delivering Spitfires to Malta! Those responsible for sending Wasp to the Mediterranean clearly understood the global nature of air power, and it is worth noting that American forces began to establish ascendancy in the air in the Pacific shortly thereafter, at the same time the British were taking the Luftwaffe’s measure in North Africa and the Mediterranean. Returning to the definitional problem, the argument that strategic bombing failed in World War II is generally made by evaluating the results of individual campaigns in isolation. Most often cited are the USAAF efforts in the summer and autumn of 1943 to collapse the German war economy by unescorted daylight bombardment and RAF Bomber Command’s night area bombing of German cities. While it is true that neither succeeded in achieving its stated objectives, both forced major reallocations of German resources that might have been more profitably used elsewhere. Of far greater importance to the subsequent course of the war, both campaigns, and in particular the American effort, depleted vital German resources that could not be replaced within available time constraints, most critically skilled fighter pilots. Thus while they may not have been victories within the analytical framework borrowed from warfare on land and at sea, both had long term consequences that contributed powerfully not only to allied victory in the air, but to the defeat of Nazi Germany. So with an understanding that there is much that we do not understand about the nature of air warfare, let us turn to my second proposition, that aircraft design was a key variable in determining the strategic effect of airpower. This proposition, like my first one, is uncontroversial, although here the lack of controversy is mostly due to a lack of systematic examination of the problem. Almost by definition, well-designed aircraft have superior performance and should thus bestow to their possessors tactical, and therefore strategic, advantages, or so logic would dictate. But there is a danger in this assumption, for it easy to conclude that strategic advantage obtained in the air must have flowed from superior design and that is not always the case. In fact, the seemingly straightforward relationship between quality of design and tactical advantage on the one hand and strategic effect on the other turns out to be anything but. As a multitude of cases demonstrate superiority in numbers or employment tactics, acting together or independently, can do much to offset performance disadvantages. That part of the puzzle is generally understood. Not so well understood or systematically explored is the fact that design determines much more than performance in the narrow sense: speed, meneuverability, range, offensive capabilities, resistance to battle damage, and the other factors that influence tactical effectiveness. By predicting cost and ease of production, design sets limits on how many of a given design can be built with the fiscal and human resources available. In controlling reliability and ease of maintenance, design has a major influence on in-commission rates. In establishing handling characteristics, in simple terms how easy or difficult an aircraft is to fly, design exercises a powerful influence on operational wastage. Finally, the design must be suited for the particular circumstances under which the aircraft is to be employed, and here a single performance parameter may be critical. To cite an obvious example, a bomber which is a superior design in every other respect, but which lacks the range to reach its targets is strategically useless. We are not helped much in our inquiry by the secondary literature, for little attention has been paid in detail to the connection between aeronautical design, tactical operation and strategic impact. A great deal has been written about the impact of airpower on World War II by theater, campaign, and battle, but few general accounts pay much attention to aircraft performance, let alone design. Similarly, much has been written about the aircraft with which the war was fought, their design histories, what they were like to fly, and how successful they were in combat, much of it for a buff audience. But while capturing an enormous amount of valuable information, this literature rarely addresses strategic issues. As a result of this divide in the literature, attempts to relate aircraft design to strategic effect are rare and generally limited to a single campaign or battle. The Battle of Britain is well served in this regard, but is very much the exception to the rule.11 The intersection between aircraft design and strategic effect is an enormous topic, and in addressing it I confronted major problems. The key question was which aircraft to analyze, and it struck me that it might be useful to begin by ranking World War II aircraft according to their strategic importance. Such a rank-ordering would not only reduce the scope of the inquiry to manageable proportions, it would, or so I hoped, provide an analytical lens through which to selectively identify and evaluate those performance characteristics that were strategically most important. Having identified the critical performance parameters, I could then examine the design processes that produced them. In fact, this approach proved to be productive, yielding results that were often unexpected and counter-intuitive. That approach is not without its difficulties. Comparing the strategic importance of aircraft that performed different missions in different theaters at different times poses obvious problems. The fact that aviation technology changed enormously during the period of our concern further complicates matters. In addition, we must consider counterfactuals if the inquiry is to make sense. My rankings are thus indicative rather than definitive. Still, I am satisfied that the rank ordering reflects strategic reality. I could easily justify moving many of the aircraft on the list up or down several places , but I am confident that the ranking is an accurate—albeit inexact—measure of relative strategic importance. To establish the ranking, I approached aircraft that played a major operational role in the Second World War with two questions: • How did the aircraft in question strategically affect the conduct and outcome of the war? • How would the conduct and outcome of the war have changed if the aircraft in question had not been developed and produced? Neither question can be answered in any definitive sense. This is particularly true of the second question, which requires us to consider the responses of historical actors to events that did not, in fact, transpire. But while the answers may not be definitive, asking the