The prospect of aerial attack was not ignored on the outbreak of war and on Aug 12th the Home Secretary, under Section 1 of the Defence of the Realm Act, did empower naval or military authorities to order the extinction of all visible lighting during specified hours at any defended harbour. This authority was widened about a month later, giving the Home Secretary the authority to order the dimming or extinguishing of lighting in any specified area. In London a specific order was issued by the Home Secretary on Oct 1st which resulted in drastic “dimming” of the capital.
On April 8th 1915, the authority to issue instructions on lighting restrictions was transferred to the Home Office. This step was taken due to the confused situation that arose with the Home Office, War Office, Admiralty and various local military and naval authorities all being able to issue orders on lighting restrictions. This made sense, as all these authorities had been increasingly making demands on the civil power in the shape of the local police to enforce lighting restrictions.
After a raid on the Midlands counties on 31st January 1916, lighting restrictions were extended to the whole of the UK with the exception of six western counties. Many local authorities in these exempted counties however asked to be covered in the restriction schemes.
As the defence against Zeppelins improved, Germany began to suffer increasing losses and decided that there was no future in bombing the UK with by this means. The winter of 1916/17 provided a relief from air raids to the civilian population and as aircraft raids to date had been only minor “tip and run” affairs, lighting restrictions were eased.
The problem of providing air raid warnings for the civil population would take longer to implement. At first the distribution of warnings was entrusted to Chief Constables, who were to inform the Admiralty of any aircraft heard or seen within 60 miles of London. In 1915 the area was extended to include East Anglia, Northamptonshire, Oxfordshire, Hampshire and the Isle of Wight. In April 1915, the scheme was altered to allow more of an interchange of information between Chief Constables, the Admiralty, War Office, Scotland Yard and the Railways. This led to much overlapping of information and chaotic congestion of phone lines.
Following the Midlands raid of Jan 1916, the Cabinet had made an urgent request to Lord French to prepare a new warning scheme in light of an epidemic of false reports which had caused widespread stoppages in work. The new scheme came into operation on 25th May 1916.
The scheme was based on the division of England, Wales and southern Scotland into eight “warning controls” each under a “warning controller” who represented the Commander-in-Chief, Home Forces. The warning control areas were further divided into “warning districts”, largely corresponding to the telephone organisation of the country. The military authorities were now responsible for the initiating warnings, which were disseminated by civilian telephone operators.
The main source of information of enemy aircraft movements came from an elaborate system of observer posts, manned by Home Force troops until December 1917 when they were taken over by the police.
The observation system was fully integrated with all the defence units which covered the London Area and districts to the south and south-east of London. These units comprised of coastal and inland watching posts, gun stations, balloon aprons, aerodromes and emergency landing grounds, all integrated into the London Defence Area (known as “Lada”) under General Ashmore. Each unit effectively became an observation station, the whole aim being to provide a much quicker warning of enemy air activity to allow commanders to deploy their forces to intercept the enemy. The “Lada” scheme was not in full operation until September 1918, while the last German raid on London was on May 19th, but it was a robust scheme and many elements of it formed the arrangements made during WW2 for air raid warnings and defence.
However, at first the new system still was concerned only with operational needs and did not include any arrangements for warning the public. The controversy of public warnings came to a head in May 1917 when Germany began a series of raids with twin-engine bombers, known as Gothas. The raid on London on 13th June was the worst single attack of the war in terms of casualties, with 162 killed and 426 injured when 118 high explosive and incendiary bombs were dropped on the City. Pressure began to increase for public warnings and the provision of public shelters. There was also fear of the enemy deploying poison gas against the British public, such fear no doubt spread by troops on leave.
In July 1917, the Government finally gave into demands for public warnings in London. A scheme was put in place, under the Commissioner of Police, where warnings were distributed by maroons (sound bombs fired into the air) and policemen on foot, on bicycles or in cars carrying “Take Cover” placards, blowing whistles and sounding horns. At first the scheme was restricted to daylight hours only, but extended to night time in December but with strict time limits. It was not until March 1918 that authority was given to use maroons at any time of day or night.
The Gotha raids also increased the pressure on the Government to provide air raid shelters for the public. The daylight raids during the summer of 1917 had seen large numbers of people taking shelter in the Underground stations while the moonlight raids of September had caused a certain amount of panic amongst East End residents, with many “trekking” into the comparatively safer western districts of London.
The Commissioner of Police allowed Police Stations to be used as shelters and those in charge of other public buildings followed this example. In October 1917, powers were introduced to requisition premises to serve as shelters. Sandbags were issued at the national expense. However the Government still considered the provision of shelters in other areas of the country a matter for local authorities. A good deal of work was in fact carried out in areas outside of London in adapting places for shelters such as caves and mine workings.
Although the air raids on Britain during WW1 were small in comparison to that in WW2, the authorities concluded after the war that it was a justifiable strategy for Germany in terms of the resources that had been put in place to meet the air attacks, resources that could have been used elsewhere. It has been suggested that perhaps a great strategical mistake made by Germany was not to coordinate a large air offensive on Britain with the 1918 Spring Offensives; Britain was expecting such attacks on the scale of perhaps up to 500 aircraft, which would have consumed even more resources, which were vitally needed at the Front to stem the German offensives.