State of Preparedness at the Outbreak of War
The industrial achievement of the rearmament programme should be judged by the state of preparedness which the country achieved. How much better prepared for war was the country in September 1939 than a year earlier and how much better was it able to engage in military operations in the spring of 1940 than it had been at the outbreak of war.
The supply of armaments at the outbreak of war, compared with the supply in October 1938, had improved beyond all possible dispute. Whether the improvement was sufficient to fulfil its strategic objective depends on the definition of the objective. If the sole strategic aim was to make Britain better able to withstand attack from the air then production in the year following Munich went some of the way towards achieving it.
The output of aircraft was rising. Even more importantly from the point of view of air defence, the number of modern fast fighters among the aircraft coming into production increased even more dramatically. The monthly output of Hurricanes rose from 26 in October 1938 to 44 in September 1939 and of Spitfires from 13 to 32 in the same period. The number of squadrons equipped with new aircraft had grown correspondingly.
|October 1938||September 1939|
The land defences against the bomber showed even better results. The monthly output of anti-aircraft guns increased from 56 in September 1938 to a monthly average of 85 in the last months of 1939. This rate was sufficient to increase the number of AA guns in service by a factor of four compared with October 1938. At the same time, their combined strength at the outbreak of war was only 1,650 anti-aircraft guns or about 50% of previously defined requirements.
Even more important achievement was the completion in 1939 of the most important line in anti-aircraft defence, the home chain of radar stations. This chain had been developed from scratch in the space of less than four years. In December 1935 Treasury approval had been given to the provision of five radar stations covering the Thames estuary, and in August 1937 the Treasury had sanctioned the construction of a home chain of twenty stations covering the east and south-east coasts. During the Munich crisis the Thames estuary was in continuous operation, and by the outbreak of war the country was guarded by a chain of eighteen permanent stations stretching from the Orkneys to the Isle of Wight. Much more remained to be done to complete it to the final specification, and still more was to be added to the programme after the fall of France, but radar had become an established weapon of war.
Thus by September 1939 Britain’s defences against air attack were substantially increased. On the other hand, if the strategic objective was ‘to catch up with Hitler’, then the achievement is more doubtful. The general impression is that the margin between German and British air forces had narrowed, while at the same time German superiority in land armaments increased.
On the whole, it appears very probable that in September 1939 the Luftwaffe was not as superior in the air as it had been a year earlier. Its first-line strength had grown from 2,847 in August 1938 to 3,609 in September 1939 whereas the British first-line metropolitan strength in mobilisable squadrons was 1,854 in September 1938 and 1,978 in September 1939. The German and the British figures are, of course, not entirely comparable for the definition of first-line aircraft in the two Services differed, e.g. the British figures contained ‘immediate’ reserves which the German apparently did not. To some extent, even the British figures at the two dates cannot easily be related, for in the meantime the composition of the total reserves had changed, and by the end of September 1939 the British first line was backed by 2,200 aircraft in reserve, a higher proportion than in 1938.
The general impression which these figures leave, however, was that judged by number of first-line aircraft unrelated to reserves and quality the German strength had grown somewhat faster than the British. The main advantage that Britain had gained during the period was not, however, that of numbers but that of quality. It has already been shown that from September 1938 to September 1939 more recent types of aircraft, above all Spitfires and Hurricanes, were coming into use in greater numbers. The total number of squadrons equipped with modern fighters increased during this period from 6 to 26, and the percentage of fighters in the overall production increased. It is here, in the modernisation of the fighter force, that the most important achievement of rearmament between Munich and the outbreak of war will be found.
The rate of success of RAF rearmament programme can be judged not only in hindsight of the well-documented victory in of the Battle of Britain, but also by comparison of relative improvements in British and German armies. Here, the results were highly unfavourable to the British effort. According to the estimates of the War Office, the strength of the German Army in the autumn of 1938 amounted to some 51 divisions more or less fully equipped and of a total field army of 690,000. These figures must be compared with the 106 divisions fully equipped and a total field force of 2,820,000 which Germany possessed at the time of the invasion of Poland.
Britain, on the other hand, in October 1938 was able to put into the field only 2 (two) fully-armed divisions. In September 1939 it disposed of sufficient equipment for about 5 divisions more or less adequately equipped. The final balance was therefore that of 106 versus 5. Comparison of these numbers with the effects of RAF rearmament adds much to the explanation of the contrast between the defeat of British Expeditionary Force in France and the subsequent victory in the Battle of Britain.