The RAF and Aircraft Design

Air Staff Operational Requirements 1923-1939

Colin S Sinnott

• Publisher: Routledge
• Year: 2014
• eBook ISBN: 9781135278816
• Topic: History
• Subtopic: Military & Maritime History
• Index: History

This work examines the evolution of the RAF's operational requirements for its home defence air force - for bombers to mount a deterrent counter offensive and for fighters to provide direct defence of Britain. It discusses the management processes, policies and decisions relevant to operational requirements on the basis of a detailed study of Air Ministry papers of the time. By tracing the development of operational requirements, the author exposes the thinking behind the RAF's quest for effective fighter and bomber aircraft. He describes the ideas and concepts of air warfare that were adopted in the 1920s, and shows how these evolved into the Air Staff's requirements for the aircraft which the RAF entered and fought in World War II.

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Introduction

When the Second World War started in September 1939 the RAF began hostilities with aircraft types which had been conceived, designed and developed many years earlier. They resulted from the RAF’s perception of the aircraft it would need to carry out its duty of home defence against air attack. To the RAF home defence did not mean just the interception and destruction of attacking aircraft, for it did not believe that such a defence could be effective. It believed that the most effective defence against air attack was an offensive against an enemy’s means to wage war — its industry and morale — and indeed the home defence force was first planned to have twice as many bombers as fighters.

This book is concerned with the translation of the RAF’s strategy for home defence into operational requirements, which is how the RAF stated its design aims for the fighters and bombers needed to carry out its strategy. By tracing the development of operational requirements in the 1920s and 1930s we expose the thinking behind the RAF’s quest for effective fighter and bomber aircraft. This leads to a new perspective on the origins of the design of many of the aircraft with which the RAF entered and fought the Second World War. We will see that commonly accepted descriptions of these origins are unsound, and that an authoritative account can be found in the Air Ministry’s papers of the time.

The treatment is historical. The aim is to consider Air Ministry policies and decisions in the context of their own time. The purpose is not to pass judgement from the standpoint of knowing what strategy or tactics proved to be effective, and those that did not. Nor is it to assess aircraft designs based on knowledge of those which later proved successful, and to blame the Air Ministry for not knowing what the best line of development would turn out to be. We will see that this approach puts the Air Ministry in a more favourable light than do studies based upon hindsight.

As the purpose is to trace the development of operational requirements through the interwar years, the layout of this book is basically chronological. However, it is important to view this development against the political, strategic and technological background of the period. A brief review of these topics from 1920–39 follows later in this chapter and in the next chapter, with particular attention to those aspects which influenced the RAF’s choice of operational requirements. I also depart from the strict chronological order of events to discuss fighter and bomber requirements separately over periods of a few years. This aids clarity and continuity and loses little. The reader will find that apart from the ever-present concern with relative speeds, there was little interplay between the RAF’s specification of fighter and bomber performance and armament.

In the Official History of the Design and Development of Weapons, Postan, Hay and Scott¹ explain how analyses and discussions of operational requirements were the starting point in the process of specification-tender-design-development-production through which aircraft evolved into operational use. They represented an assessment of future needs, and of the operational possibilities which might follow from the exploitation of new or developing technology. In the words of the Official History:

In the first place the tactical and strategic ideas of the Services had to be focussed [sic] on problems of aircraft or aircraft equipment. This meant considering and defining to what extent the quality of existing types met, or failed to meet, the requirements of the men who flew them and what further improvements in quality, i.e. speed, range, load etc., would be necessary. In the terminology of the RAF administration this function was described as ‘OR’ (Operational Requirements) and expressed the ‘user’ point of view in the narrower sense of the term.²

The second stage was design and development, and indeed that is the subject of the Official History. It says of the first stage:

The method in which the first of those functions, i.e. formulation of operational requirements, was fulfilled need not delay us long. The fact that it followed directly from the strategic notions of the Air Staff or from the tactical experience of the Royal Air Force made it an integral part of the Air Staff duties.³

We will see that in many respects the Air Staff’s views on these matters had their roots in the political situation of the early 1920s and the policies then adopted by the Air Ministry. That this is so for the doctrine of strategic bombing is well known. What is less well known is that the principles which governed the types of aircraft which were sought were also laid down at that time and that these persisted through to the 1930s.

In that decade the vital planning task of assessing future operational requirements had become particularly complex. There was no recent combat experience from which operational lessons might be learnt, and until late 1934 there was uncertainty as to the potential enemy. Most crucially, very rapid advances in aeronautical engineering were taking place. These offered new operational possibilities, but also new threats, with the ever-present risk of commitment to a level of technology which might have become outdated by the (unknown) time that hostilities arose. It was against that background that decisions were made which led to the majority of the home defence aircraft types that the RAF operated in the early years of the Second World War. Some of these types, albeit much modified, formed the backbone of the RAF throughout the war.

A study of the development of operational requirements highlights debates within the Air Ministry on the expected operational and tactical effectiveness of future aircraft. Although the Air Ministry was fully aware of the need to exploit the air-fighting potential of advances in aeronautical engineering and armament, we will see that this did not alter its belief in the effectiveness of bombers and bombing. In consequence, there was much concern with the problem of the direct defence of London against hostile bombing formations. This problem was not thought to have been solved even by the heavily-armed fighters developed in the 1930s. Fears that single-seat fighters would be ineffective in breaking up formations of bombers led to much effort being put into the search for a superior type of fighter.

It was the presumed ineffectiveness of direct defence which led the RAF to adopt the strategy of a counteroffensive to deter or mitigate air attacks on London. It planned to implement this through precision bombing in daylight. When Germany replaced France as the potential enemy, this brought a requirement for deep penetrations of hostile air space. It was the consequent need for high speed and heavy armament — not a change in bombing policy — which led to a move towards heavier bombers in the 1930s. Paradoxically, the heavy night bombers of 1941–45 were a product of designs to these day bomber requirements, since they included plans for very heavy bomb loads based upon overload operation using exotic schemes for assisted take-off. When these were not forthcoming, heavy bomb loads were achieved by building larger airfields. We will see that attainable fighter performance was also dictated by airfield size.

The issues outlined in the preceding paragraphs are largely ignored in the copious literature on the RAF’s aircraft of the Second World War. How has this come about?

It is likely that a prime source of omission and misrepresentations of Air Ministry aircraft development policy is the Official History from which the above quotations were taken. This was published before Air Ministry files were open to the public. We have seen that the authors of that history took the view that the formulation of operational requirements, ‘need not delay us long’. Unfortunately, they then proceeded to comment on the origins of RAF aircraft, largely it appears on the evidence of their discussions with the aircraft industry. Inevitably, this led to the attribution of most new ideas to industry, and the omission of...

Table of contents

• Cover
• Half Title
• Title Page
• Copyright Page
• Table of Contents
• List of Illustrations
• Series Editor’s Preface
• Acknowledgements
• List of Abbreviations
• 1 Introduction
• 2 Management and Technological Background
• 3 The Application of Policy, 1923–30
• 4 The Quest for Speed: From Bulldog to Spitfire
• 5 The Quest for Fighter Firepower
• 6 Bombers to Attack France
• 7 Bombers to Attack Germany
• 8 Before the Storm: Operational Requirements, 1937–39
• 9 RAF Policies Tested in War
• Appendix: Air Ministry Posts and Holders
• Bibliography
• Index