Strategic bombing during World War I

German airship Schütte Lanz SL2 bombing Warsaw in 1914

The introduction of strategic bombing during World War I (29 July 1914 – 11 November 1918) was led by Britain and France for the Entente and Germany for the Central Powers. All the major powers eventually engaged in such bombing, and the capital city of each major belligerent was struck, save Rome. Plans for a multi-national air force to strike at Germany, however, never materialised. Strategic bombing is the species of aerial bombing that targets the enemy's civilian and industrial infrastructure, its will or ability to fight, and in general is implemented to further a country's overall strategy. The aerial bombing of cities—or "terror bombing"—intended to destroy the enemy's morale was introduced by the Germans in the opening days of the war.

The lessons of strategic bombing were essential to the development of dedicated bomber aircraft, like the light bomber and heavy bomber, during World War I. Initially bombs were dropped by hand and aimed by the naked eye, but by the end of the war crude bombsights had been invented. The advent of air raid warnings, sirens and shelters can be dated to World War I, as can the design of dedicated anti-aircraft artillery and the role of interceptor aircraft. Many of the advocates of strategic bombing during the interwar period, such as Italy's Giulio Douhet, America's Billy Mitchell, and Britain's Hugh Trenchard, had commanded aircraft during World War I. The improvements in aircraft technology during and after the war convinced many that "the bomber will always get through", which affected planning for strategic bombing in World War II.

Germany

Main article: German strategic bombing during World War I

The first strategic bombing in history was also the first instance of bombs being dropped on a city from the air. On 6 August 1914 a German Zeppelin, a type of rigid airship, bombed the Belgian city of Liège. In Britain, fear of the Zeppelin as a weapon of war preceded its actual use as one, as even before the World War the British public was gripped by "zeppelinitis". Within months of the war' start, Germany had formed the Ostend Carrier Pigeon Detachment, in fact an airship unit intended for the bombing of English port cities. Flying out of ports in northern France or Belgium, the Germans had tailwinds going to Britain and having dispensed their payload were lighter coming back.

During the First Battle of the Marne, a German pilot flying aerial reconnaissance missions over Paris in his Taube regularly dropped bombs on the city. The first drop consisted of five small, hand-lobbed bombs and a note demanding the immediate surrender of Paris and the French nation. Before the stabilisation of the Western Front, the German Taubes dropped fifty bombs on Paris, slightly damaging Notre Dame Cathedral.

The first extended campaigns of strategic bombing were undertaken against England by the German Empire's fleet of Zeppelins, which were the only aircraft capable of such sustained activities so far from their bases. These bombings were approved on 7 January 1915 by Kaiser Wilhelm II, who forbade attacks on London, fearing that his relatives in the British royal family might be injured. (These restrictions were lifted in May, after British attacks on German cities.) The first attacks on England came on 9 January around Yarmouth and King's Lynn. The Zeppelin proved too costly compared to airplanes, too large and slow a target, too cumbersome, its hydrogen gas too flammable, and too susceptible to bad weather, anti-aircraft fire (below 5,000 feet) and interceptors armed with incendiary bullets (up to 10,000 feet) for the Imperial German Army (Reichsheer), which abandoned its use in 1916. The Imperial German Navy (Kaiserliche Marine) continued to use the Zeppelin through the war. In all, fifty-one raids on Great Britain were committed, the last by the Navy in May 1918. The "year of greatest intensity" of the strategic bombing of England was 1916. Germany employed 125 airships during the war, lost more than half and sustained a 40% attrition rate of their crews, the highest of any unit.

In May 1917 the German began replacing Zeppelins with G-planes and R-planes for raiding Britain. Large aircraft with multiple engines capable of 80–100 miles per hour at upwards of 14,000 feet and over a ton of ordnance, with range enough to cross the English Channel, R-planes flew twenty-seven missions, seventeen at night and eighteen against London, between 25 May 1917 and 20 May 1918. The targets of these raids were industrial and port facilities and buildings of the defence ministry, but few of the bombs made their targets, most hitting schools, hospitals, homes, hotels and private businesses and killing civilians. Although the German strategic bombing campaign against Britain was the most extensive of the war, it was largely ineffective. Only 300 tons of bombs were dropped, resulting in £2 million of damage, 1,400 dead and 4,800 injured. In the autumn of 1917, however, over 300,000 Londoners had taken shelter from the R-planes, and industrial production had taken a hit as a result.

Britain

The Royal Naval Air Service (RNAS) undertook the first Entente strategic bombing campaign on 22 September 1914, repeating it on 8 October, when it bombed the production line and hangars of the Zeppelin facilities in Cologne and Düsseldorf. The airplanes carried twenty-pound bombs, and at least one airship was destroyed. On 21 November, the RNAS flew across Lake Constance to bomb the Zeppelin factories in Friedrichshafen and Ludwigshafen. On 25 December the Cuxhaven Raid became the first attack by sea-based airplanes on a strategic target.

According to the history of strategic bombing Lee Kennett, when William Weir, the President of the Air Council in 1918, told Hugh Trenchard that it was not necessary to worry about accuracy during strategic bombing raids, the general replied that "all the pilots drop their eggs into the centre of town generally." After the formation of the Royal Air Force on 1 April 1918, the British Prime Minister David Lloyd George promised to repay Germany for its air raids "with compound interest". On 19 July, the first carrier-based air raid in history, the Tondern raid, was launched against a German Zeppelin yard.

On 6 June 1918 the British formed the Independent Force under Major General Hugh Trenchard to engage in long-range bombings deep in German territory at industrial targets. Although some missions were undertaken with De Havilland DH9s and Handley Page 0/400s, the war ended before Britain's four-engined Handley Page V/1500 bomber, designed to drop 7,500 lbs on Berlin, entered service. Ultimately, retaliatory bombings on German cities brought on German retaliation against, not British, but mostly French cities, which evoked sharp disagreement between British and French leadership concerning the strategy of such bombing and allocation of resources away from the Western Front. Still, the British dropped 660 tons of bombs on Germany, more than twice what Germany had managed to loose on England.

France

German airship bombing Calais on the night of 21–22 February 1915

France formed the first strategic bombing unit in history, the Group de Bombardment No. 1 (GB1), in September 1914. The French were reluctant to bomb targets on their own soil, even if occupied by the Germans, and were more wary of German retaliation than the British, given the easy reach for German bombers of French cities. Nevertheless, GB1 raided far behind the front, concentrating on the German supply network and troop concentrations, a strategy designed to directly aid the French Army on the front. The French favoured light bombers, often redesigning reconnaissance craft for that purpose. The Breguet 14 of 1917 remained in production until 1926.

On 4 December 1914 French pilots carried out the first Entente bombing of a city when they dropped propeller-guided bombs on Freiburg im Breisgau. In 1916 a French Nieuport flew over Berlin and dropped leaflets assuring the people that while they could have been bombs, "Paris did not make war on women and children". He was forced to land sixty miles short of Russia, his intended destination.

Italy

The Kingdom of Italy had conducted the first aerial (tactical) bombing campaign in history on 1 November 1911 during the Italo-Turkish War, when Giulio Gavotti dropped bombs by hand on Turkish positions in the Libyan desert. Two dirigibles and nine fixed-wing aircraft were sent by Italy to Libya during that conflict. During World War I, like France, Italy did not wish to bomb centres of civilian population, behind enemy lines during World War I, because many of the obvious targets had a high number of Italian residents or were in territories Italy had plans to annex after the war, per the Treaty of London (1915). Like Russia, Italy possessed heavy bombers before its entry into the war. Giovanni Battista Caproni had developed the multi-engine Caproni Ca.1 in 1914.

In August 1915, the Ca.1s were placed in the 21° Squadriglia of the Corpo Aeronautico Militare. In October–November 1915, the Ca.1s attacked Austo-Hungarian railroads and supply depots.

Russia

The Russian Empire possessed the only heavy bomber in the first year of the war, and it outdistanced all the others. Designed for reconnaissance and bombing, the Sikorsky Ilya Muromets (IM) could carry 1,100 lbs of bombs and up to sixteen personnel and a dog, and go for up to five hours or 300 miles. In August 1914 the Russians grouped their four Sikorskys in a unit designed for strategic bombing and based them near Warsaw in December. Cities were not the main targets on the Eastern Front, rather those were supply depots, troop concentrations and transportation networks, especially railway yards and stations. By March 1918, when Russia left the war, around seventy Ilya Muromets had been constructed and they had flown over 350 bombing or reconnaissance missions along the entire Eastern Front.

Austria–Hungary

Strategic bombing by Austria–Hungary was limited, mostly confined to Italian targets on the Adriatic. Nonetheless, Austro-Hungarian pilots based out of Pula flew forty-two bombing missions over Venice after the Italian Front had been advanced to within a few miles. The Chiesa degli Scalzi, near the Ferrovia train station, was damaged, including two ceiling frescoes by Giovanni Battista Tiepolo. A particularly severe raid was carried out on 27 February 1918, hitting central Venice and sending many Venetians to take refuge in Giudecca and the Lido. A letter from Ralph Curtis to Isabella Stewart Gardner written in September 1915 explains how the Venetians instituted blackout during the bombings:

The mosquitos from Pula come buzzing over nearly every fine night, and drop bombs for half an hour or so. . . . Venice is like a lovely prima donna in deep mourning. All the gilded angels where sack-cloth painted dirty grey. Anything that shines is covered. At night all is as black as in the dark ages. "Serrenos" call out "all is well" every half hour. But when danger is signalled the elec[tric] light is cut off, sirens blow, cannon firebombs explode and the whole city shakes on its piles. All the hotels but the Danieli's are hospitals.

The Venetian writer Alvise Zorzi attributes "the final rupture of the continuity of Venetian customs and culture" to the Austro-Hungarian bombing campaign.

Bibliography

• Lee Kennett. The First Air War, 191418. New York: Free Press, 1991.
• Lee Kennett. A History of Strategic Bombing. New York: Scribner, 1982.