It had been recognised for some years before the outbreak of war in 1914 that the new wonder of the aeroplane constituted a threat which had never before been posed. Namely, the possibility that aircraft could fly across the Channel from Germany, the likely enemy, and inflict damage and casualties on areas which, until then, had been safe. In addition, although aircraft design was still in its infancy, and bomb loads were small, Zeppelins, of which Germany was known to possess at least ten, could deliver a big punch. And not only were docks, munitions factories and industrial areas at risk but the effect on civilians and their morale was a factor hitherto untested.
However, attempts to galvanise weapon development and production in the immediate pre-war period met with little success. In April 1914 there were just 26 guns in position to protect the whole of Britain from aerial attack. Most of these were field guns on improvised mountings to enable them to fire skywards, notably the one-pounder pom-pom, a quick-firing gun which had been designed by Sir Hiram Maxim in the 1880s and offered to the British Government. This offer had been turned down, but when the gun was subsequently used against British troops in the Boer war minds were changed and the gun was hastily adopted.
When the air offensive came, in 1915, it was indeed the Zeppelin which at first proved to present the biggest danger. Carrying a five-ton bomb load, it had a range which included not only the whole of the south and east coast from Dorset to Scotland, but also the industrial Midlands. Nor could much be done to stop them. With battles raging across the other side of the Channel, the great majority of the Royal Flying Corps machines had been sent to France to support the British Expeditionary Force. As a consequence, most of the aircraft left in Britain belonged, not to the RFC, but the Royal Naval Air Service and it was therefore decided to incorporate the remaining RFC machines into the naval unit. As a presage of events in a later conflict, this brought all home air defence, including anti-aircraft guns, under the responsibility of the First Lord of the Admiralty...........Mr Winston Churchill.
Meanwhile, to add heavier fire power to the lightweight one-pounder pom-poms more field artillery pieces had been adapted for use against aircraft. These included the 18-pounder, the French 75mm and the Royal Horse Artillery 13-pounder. However, it was the development of a purpose-designed AA gun, the 3inch 20cwt, which really added impact to the defences and took the principle and reality of ack-ack defence to a new level. In its 1916 form, this gun threw 16-pound shells into the air at a rate of 16-18 rounds per minute, with a ‘ceiling’ of 22,000 feet. So successful was this weapon that it was retained after the war as the standard AA gun and saw service throughout the early part of World War Two until replaced by the 3.7 inch.
By the end of 1916 there were 367 guns defending London, the Midlands, the East Coast, Dover and Harwich and the combined forces of AA gunnery and fighter interception had effectively overcome the threat of the airship as more and more were either shot down or crashed through mechanical failure.
This respite was, however, short-lived as a new aerial invader now appeared in the sky - the Gotha twin-engined heavy bomber. With the demise of the Zeppelin the German High Command had turned to aircraft in a dramatic way. On 25 May 1917 sixteen Gothas crossed the Essex coastline in formation. Each had a crew of three and, cruising at 80 miles per hour, could carry a bomb load of 1000lbs. While this was a far lighter load than the Zeppelin could carry, the Gotha’s small size, compared to the vast bulk of the airship, made it infinitely more difficult to hit by anti-aircraft fire, or for that matter, by attacking British aircraft. The bomb-carrying deficiency could be overcome by simply using more of them.
In the ensuing weeks and months many more Gotha attacks would cross Essex on their way to bomb London. Formations of twenty-plus became commonplace. Even forty was not unusual. Casualties far exceeded those that had been suffered from airships. The heaviest of these came on the night of 3 September 1917 when 130 naval ratings died as their barracks at Chatham was hit by two 100lb bombs.
The final throw of the German air offensive came with the development of the Giant, a multi-engined "flying fortress" bristling with machine-guns. This monster could carry a bomb load of 3000lbs, over a ton of high explosives. They first made their appearance in January 1918, their distinctive sound coming from 260HP Mercedes engines which both pushed and pulled the aircraft through the air. There were a number of raids by both Giants and Gothas between January and May 1918 but by this stage of the war both the aerial and ground-based defences had stiffened enormously since their early beginnings and air raids over Britain had become a much more hazardous undertaking. By June 1918 raids had ceased altogether, 469 anti-aircraft guns were in position throughout the country and squadrons of British fighter aircraft now patrolled the skies where Zeppelins once flew.
© Fred Nash, ECC