Kaiser Bill’s Air Force: Gotha IV Strategic Bomber

Kaiser_Gotha_IV_frontThe model of  Gotha IV aircraft 604 that was exhibited at the Cheltenham GWR Modellers Exhibition in October 2007 is now on display at Jet Age Museum in Staverton .




 1917 was to be a year of change, with both Russia leaving the Great War and the United States of America joining the fray on the side of France and Britain.
But in March of that year, as the slaughter continued on the Western Front, it seemed that at least the skies over England were now safe. For eight consecutive months no Zeppelin had dared to cross the North Sea from Germany. Little did those who kept the home fires burning know of the Kaiser’s new secret aerial weapon.

With a wingspan of 78 feet, the Gotha IV heavy bomber dwarfed every other aeroplane, could reach speeds of 88 mph and had a ceiling of 16 000 feet, well above the reach of any Allied fighter. The twin engined Gotha IV even featured an early oxygen system, allowing the three man crew to fire any of three machine guns and generally function at such a high altitude. More importantly for its intended angrif (objective ) of England, the Gotha could carry a bomb load of over 2 200 lbs, ten times more than any other Great War fighting aircraft and was unique in being able to reach Britain from its continental bases.

The Gotha G I – first flown in July 1915 – was based on an underpowered seaplane design. Nevertheless, the German Imperial Air Service contracted series production to Gothaer Waggonfabrik, whose chief engineer – Hans Burkhard – simplified and refined the fabric-skinned bomber concept. Gothaer Waggonfabrik built about 20 G I aircraft – powered by two 150 hp Benz. Bz.III engines – in 1915.

The succeeding Gotha G.II – armed with two machine guns and first flown in March 1916 – was an entirely new Hans Burkhard design with the forward section of the fuselage skinned in plywood. The fuselage was mounted on the lower wing with two nacelles, each containing fuel and oil tanks beneath a geared eight-cylinder 220 hp Mercedes D.IV prime mover. Ten G.II entered service in autumn 1916, but were withdrawn in the spring of 1917 after repeated engine crankshaft failures.

The G.II was succeeded by the G.III, which featured a reinforced fuselage with an extra machine gun firing through a ventral trapdoor. The failed eight-cylinder Mercedes D.IV was replaced by the new six-cylinder 260 hp Mercedes D.IVa engine. Most of the 25 G.III aircraft produced operated in the Balkans but despite some strategic successes September 1917 saw all surviving aircraft relegated to training units.

Experience with the G.III showed that one rear gunner could not efficiently operate both the dorsal and ventral positions. Burkhard’s ultimate solution was the “Gotha tunnel,” a trough connecting an aperture in the upper decking with a large opening extending across the bottom of the rear fuselage. The Gotha tunnel allowed a gunner at the dorsal position to depress his gun into the aperture and fire through the fuselage at targets below and behind the bomber. A ventral machine gun could still be mounted as an extra deterrent to stalking enemy fighters.

Some sources have suggested that the design of the G IV was also influenced the German capture of a brand new Handley Page 0/400 bomber in early 1917. The G.IV fuselage was fully skinned in plywood and complaints of poor lateral control, particularly on landing, led to the addition of ailerons on the lower wing. A large section of the trailing edge of the 77 ft 9 in (23.70 m) upper wing was also removed to clear the pusher propellers.

In November 1916, Gothaer received a production order for 35 aircraft subsequently increased to 50 in February 1917. A further 80 aircraft were ordered from the Siemens-Schuckert Werke (SSW) and 100 from Luft-Verkehrs-Gesselschaft (LVG). Landing accidents constituted 75 percent of all operational losses, and one weakness of the Gotha I to IV series was that fuel tanks could rupture directly next to the hot engines.

The Gotha V was to solve this problem with central fuselage fuel tanks, and also featured shock landing gear and a biplane tail for added directional stability. However, the performance of Gotha Vs suffered from the use of unseasoned wood and poor quality fuel made necessary by Allied blockades.

The “England Geschwader” was formed with 36 Gotha bombers in March 1917  at St. Denis-Westrem and Gonterode on the coast of occupied Belgium with the aim of destroying the morale of the British civilian population.  However, British raids on these bases later forced a retreat to Mariakerke and Oostracker

Despite this, formations of G IV could certainly cover each other with defensive fire from their 7.92mm Parabellum machine guns in the way that lone Zeppelins could not. The G IV could also carry 1 100lb of bombs in under wing cradles, as well as six further bombs in a bay between the pilot and rear gunner.

At 5.00pm on 25 May 1917, 21 Gotha bombers crossed the Essex coast in line astern at 12 000 feet and flew unhindered up the Thames estuary. However, as a thick haze of smoke over London made accurate bombing impossible, the formation banked to port and headed for their secondary objective of Folkestone, the major supply port for the British armies in France.

The sky over Kent was clear and the holiday resort – despite the privations of total war – was thronged with visitors for the start of the annual Whitsun weekend. The Gothas approached from the landward side at 14 000 feet, spent ten minutes over the target and flew back out to sea, closing into a diamond formation so that the combined fire power of 63 machine guns could be brought to bear on any pursuing fighters.

None appeared, but back in Folkestone 60 bombs had left 95 people dead and 260 injured – more havoc than any Zeppelin had ever wrought. An eye witness described how “The whole street seemed to explode, with smoke and flames everywhere. Worst of all were the screams of the wounded and dying, and mothers frantically searching for their children.”

The Gothas of the “England Squadron” finally attacked London on their third attempt on 13 June 1917. On a beautiful clear day 20 Gothas reached Liverpool Street, dropping three bombs directly on the railway station and more on the Royal Mint and densely populated area nearby. 162 people were killed and 432 were injured before the German aircraft returned to base without loss. Of these, 18 were children from Upper North Street School in Poplar. They received the largest funeral that the East End had ever seen and are commemorated by a monument in a park near their school.

Similar attacks on London and the Channel ports continued throughout the summer of 1917 – one stray bomb killed 131 Naval ratings asleep in their barracks at Chatham – although improved defence systems forced the bombers to switch to night time raids.

Flying up the Thames in daylight, these aircraft had to carry less than their full bomb load to stay at a height over 10 000’ out of range of British fighters. However, although night raid could be made at lower altitudes, SE 5As and Sopwith Camels were able to inflict heavy losses on the insurgents by early 1918.

London in particular was protected by a ring of searchlights and anti-aircraft guns and fighter patrols by both the Royal Flying Corps and the Royal Naval Air Service. Like the novel deployment of barrage balloons with steel cables designed to cut through the wings of enemy aircraft, these were co-ordinated from a newly created facility in Horse Guards Parade.

However, by September 1917, the Luftstreitkrafte had developed an even more powerful bomber. Nicknamed the “Giant”, this four engined biplane had a wingspan of 138 feet, a crew of nine, six defensive machine guns, a gyro compass, a radio direction finder and an electrically released two ton bomb load. Ground radio stations also monitored each aircraft’s flight path so that for the first time in history an aircraft could fly blind in bad weather.

At this time the England Squadron had 92 operational Gothas and five Giants and night time raids continued into 1918. At one point, nearly half a million Londoners were camped out in the Underground.

The biggest aerial assault in history then began in May 1918 with 38 Gothas and 3 Giants. However, ten Gothas had to turn back before they had even reached the English coast and under intense attack only 16 Gothas arrived over London. Seven were shot down and the raid only caused minimal damage.

Despite this, in 22 raids on Britain Gotha IVs dropped 2 500 bombs with a combined weight of 83 tons and killed over 800 people for the loss of 43 Gothas and two Giants.

Had these raids begun earlier the outcome of the Great War might have been significantly different but with Germany and its allies being starved into submission by British naval blockades their main legacy was to prepare Britain for the next major aerial attack from the Continent in 1940.

The model of a Gotha IV aircraft that was exhibited at the Cheltenham GWR Modellers Exhibition in October 2007 is now on display at Jet Age Museum in Staverton . However, to place the Gotha series of twin engined biplanes in their historical context, this feature examines the German strategic bombing campaign that began with Zeppelin airshipsMore immediately though, in an era when even dachshunds were being kicked off pavements for being German, the name of Hans Burkhard’s twin engined bombers also influenced the decision of King George V to change his family name from Saxe-Coburg-Gotha to the Windsor that we know today.

All Gotha bomber aircraft were destroyed after World War One under the terms of the Treaty of Versailles.



1911 saw Handley-Page produce the twin engined O/100 heavy night bomber, the largest aircraft built in Britain and featuring folding biplane wings, an enclosed cabin with bullet-proof glass and armour protection, and engines mounted in armoured nacelles. Improvements to the O/100 resulted in the O/400, powered by twin 360hp Rolls-Royce Eagle VIII engines, of which more than 450 were built in the UK in 1918/19. Some of these made useful interim 10-seat civil transports after the Armistice and provided the basis for the twin-engined Hyderabad bomber that entered RAF service in the 1920s.Indeed, long-range bombing raids were made against Germany in response to the demands for retaliation after the Gotha raids on England. Twin engined Handley Page 0/100s (the so-called “Bloody Paralysers”, pictured left) were now available and from bases in France they and single engined DH4s and DH9s made raids on Germany in the winter of 1917-18 (weather permitting) and through to June 1918.
More ominously, in his report which led to the amalgamation of the Royal Flying Corps and Royal Naval Air Service into the Royal Air Force on 1 April 1918, General Jan Smuts wrote

“There is absolutely no limit to the scale of its future independent war use. And the day may not be far off when aerial operations with their devastation of enemy lands and destruction of industries and populous centres on a vast scale may become one of the principal operations of war, to which the older forms of military and naval operations may become secondary and subordinate.”

Furthermore, on 13 May 1918, the long range ground attack machines of the new RAF were organised into an “Independent Force” tasked with conducting a strategic bombing campaign against Germany without concern for land battles and initially independent of the Allied Supreme Commander.

Although this “Independent Force” would have to face wholly new challenges in terms of numbers of aircraft, accuracy of navigation, target planning and the overall effectiveness weighed against the cost – it took the war to German cities like Frankfurt, Cologne andMannheim for the last 5 months of the war.

The main targets were the chemical factories (producing poison gas), aeroplane factories, blast furnaces (easy to find) and railways. Operations were carried out both by day and by night against more and more effective air defence forces and had the war not ended when it did, plans were already made for a big Handley Page V/1500 4-engined bomber, capable of carrying thirty 250 lb bombs, to go into action against Berlin from bases in England.

As it was, the Handley Page 0/400s developed from the earlier 0/100 design and entering service in September 1918 could carry a 1 650lb bomb.

While the tonnage of bombs dropped appears relatively small – 550 tons in 239 raids -between 6 June and 10 November 1918 – the evidence collected after the war suggests that the extent of the disruption of the German war effort was out of all proportion to either the size of the bomber force or the material damage it caused. The air offensive had a considerable effect, particularly on the morale of the German people that was deeply shaken.

By 1918, Germany was a war-weary nation that was dispirited by huge losses on the battlefields and was near to starvation from the Allied naval blockade. Consequently, there was some loss of production of war materials from the factories of Germany. But the most significant effect of the raids was that large numbers of German forces were diverted into air defence units to counter the bombers at the time when the German war effort was under its severest strain both at home and on the battlefield.

Air_Sikorsky BolshoiHowever, perhaps the greatest technological impact of the race to develop strategic bombers during World War I came via one man – Igor Ivan Sikorsky.
On 13 May 1913 twenty four year old Sikorsky’s Bolshoi ( meaning “Great” in his native Russian and pictured above ) became the first four engined aeroplane to fly, the first to have a large enclosed passenger cabin and was the largest aeroplane in the World. Powered by four 100 bhp engines and weighing 9 000 lb, the Bolshoi made a 1 hour 54 minute flight with eight passengers aboard on 2 August 1913 and made 53 flights in all.

From this ground breaking passenger transport came an improved design – the Ilya Mouriametz, first flown on 10 December 1913 and introduced to 16 passengers on 25 February 1914. Named after a legendary Knight from medieval folklore, the 10 000 lb four engined machine featured electric light, wicker chairs, bathroom and bedroom and was built at the Russo-Baltic Carriage Factory in Riga.

With the coming of war, Sikorsky modified the 70′ long 102′ wingspan Ilya Mouriametz to become the World’s first purpose-designed bomber. It was initially powered by four German-made 100 bhp Argus engines although few of the aircraft put into production for the Russian Imperial forces were identical due both to continuous development and a shortage of powerplants. In fact some of the 73 Ilya Mouriametz built up to 1918 did not have four of the same type of engine!

Despite this, the Ilya Mouriametz could carry bombs of up to 1 200 lb and a crew of up to twelve, nine of these being defensive machine gunners, and still have a range of between 400 and 600 miles. Operations began on 12 February 1915 when an Ilya Mouriametz V Kievsky II variant dropped 600 lb of bombs on the German held railway station at Mlava, causing significant damage.

German aviators were reluctant to engage Ilya Mouriametz due to their strong defensive fire and turbulent wake and only one of the Russian bombers was lost to fighter defences – after shooting down three of the four Albatros fighters sent to attack it. Ilya Mouriametz squadrons also pioneered formation bombing raids, night bombing and photographic bomb-damage assessment.

However, Russian air forces fragmented following the Revolution of February 1917 and the last flight of an Ilya Mouriametz was in 1922, by which time Igor Sikorsky had emigrated to America.

In his adopted land, Sikorsky designed such notable large monoplane flying boats as the Martin 130 and Sikorsky S.42 of 1934 and the Boeing 314 Clipper of 1938 although his greatest contribution to flight was the first practical and mass produced helicopter – the R-44 of 1944. Born in 1889, Igor Ivan Sikorsky was to survive until 1972.

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