R38
Encyclopedia
The R38 class (also known as the A class) of rigid airship
s was designed for Britain's Royal Navy
during the final months of World War I
, intended for long-range patrol duties over the North Sea
. Four such airship
s were originally ordered by the Admiralty
, but orders for three of them (R39, R40 and R41) were cancelled after the armistice with Germany and work on the lead ship
of the class, R38, continued only after the United States Navy
had agreed to purchase her. At the time of her first flight in 1921, she was the world's largest airship. The American designation ZR-2 was already painted on the hull before its four completed test flights and in preparation for a final trial flight and delivery to Lakehurst. On 23 August 1921, ZR-2 was destroyed by a structural failure while in flight over the city of Hull
and crashed into the Humber estuary
, killing 44 out of the 49 crew aboard. This disaster resulted in more deaths than the more famous Hindenburg Disaster
that killed 35.
, followed by orders for three more ships to the same design. Construction of R38 commenced at Cardington, Bedfordshire
in February 1919. Certain modifications to the original design had to be made to allow the R38s to be built within the available construction shed
. As a result, two of the power cars were moved up to the sides of the structure to save height, the number of gas bags was reduced from 16 to 14 and there were fewer girder rings around the envelope.
Later in 1919, several airship orders were cancelled as a peacetime economy measure, including the three R38 class ships on which work had not yet commenced: R39, R40, and R41. In a further round of cutbacks, the cancellation of the unfinished R38 also appeared imminent, but before this was actually carried out, the project was offered to the United States in October.
The United States Navy
had decided that it wanted to add rigid airships to its fleet and originally intended to get some German Zeppelins as part of the wartime reparations but these were deliberately destroyed by their crews in 1919. An order was placed with the Zeppelin company for a new craft (to be paid for by the Germans) and to go with it they planned to build one in the United States. With the news that the R38 had been cancelled the possibility of buying it was investigated. An agreement was reached in October 1919 for purchase at $2,000,000 and work on the airship recommenced. Changes included a requirement for mast mooring gear, which added a ton to the bows which was then balanced by ballast at the rear. This modification along with the weight savings in the design made a craft that was weak longitudinally. The Germans had made lightweight high altitude Zeppelins towards the end of the war and part of one of these, the L 70, had been recovered from the North Sea after it was shot down in August 1918. However it was not realised that the manoeverability of these Zeppelins was deliberately restricted, especially in the rate and tightness of turn, due to the lightweight structure.
The R38 made its first flight on 23 June 1921 where it flew registered as R-38 but with US insignia ZR-2 painted on. It flew to RNAS Howden
where the full conversion to American livery was to be made. After some modifications to the rudder and elevators, a second test flight flew on 17 July to Howden for airworthiness and acceptance trials. Some testing of the re-balanced control surfaces was performed on this flight which resulted in severe pitching. When in the shed at Howden, examination of the structure revealed damage to several of the girders. These were replaced and others were strengthened but there were increasing doubts being expressed about the design including some by Air Commodore
E. M. Maitland
, the very experienced commander of the Howden base.
Following a spell of bad weather the airship was finally walked out on 23 August and in the early morning took off for her fourth flight which had an intended destination of RNAS Pulham
, Norfolk where she could be moored to a mast, a facility lacking at Howden. In the event mooring proved impossible because of low cloud and so the airship returned out to sea with the intention of running some high speed tests and then returning to Howden. The speed runs proved successful and as there was still daylight left it was decided to try some low altitude rudder tests to simulate the effects of the rough weather that could be expected on the Atlantic crossing. At 17:37, fifteen degrees of rudder was applied over the city of Hull
. Eye witnesses reported seeing creases down the envelope and then both ends drooped. This was followed by a fire in the bow and then a large explosion which broke windows over a large area. The airship had failed structurally and fell into the shallow waters of the Humber estuary. Sixteen of the 17 Americans and 28 of the 32 Britons in the crew were killed. The only American to survive was Rigger Norman C. Walker. The five who survived were in the tail section. A memorial was erected at Hull, Yorkshire
.
The Committee of Enquiry that was convened to investigate the disaster concluded that no allowance had been made for aerodynamic stresses
in the design and that while no loads had been placed on the structure during testing that would not have been met in normal use, the effects of the manoeuvres made had weakened the hull. No blame was attached to anyone, this was not part of the committee's remit.
Rigid airship
A rigid airship is a type of airship in which the envelope retained its shape by the use of an internal structural framework rather than by being forced into shape by the pressure of the lifting gas within the envelope as used in blimps and semi-rigid airships.Rigid airships were produced and...
s was designed for Britain's Royal Navy
Royal Navy
The Royal Navy is the naval warfare service branch of the British Armed Forces. Founded in the 16th century, it is the oldest service branch and is known as the Senior Service...
during the final months of World War I
World War I
World War I , which was predominantly called the World War or the Great War from its occurrence until 1939, and the First World War or World War I thereafter, was a major war centred in Europe that began on 28 July 1914 and lasted until 11 November 1918...
, intended for long-range patrol duties over the North Sea
North Sea
In the southwest, beyond the Straits of Dover, the North Sea becomes the English Channel connecting to the Atlantic Ocean. In the east, it connects to the Baltic Sea via the Skagerrak and Kattegat, narrow straits that separate Denmark from Norway and Sweden respectively...
. Four such airship
Airship
An airship or dirigible is a type of aerostat or "lighter-than-air aircraft" that can be steered and propelled through the air using rudders and propellers or other thrust mechanisms...
s were originally ordered by the Admiralty
Admiralty
The Admiralty was formerly the authority in the Kingdom of England, and later in the United Kingdom, responsible for the command of the Royal Navy...
, but orders for three of them (R39, R40 and R41) were cancelled after the armistice with Germany and work on the lead ship
Lead ship
The lead ship or class leader is the first of a series or class of ships all constructed according to the same general design. The term is applicable military ships and larger civilian craft.-Overview:...
of the class, R38, continued only after the United States Navy
United States Navy
The United States Navy is the naval warfare service branch of the United States Armed Forces and one of the seven uniformed services of the United States. The U.S. Navy is the largest in the world; its battle fleet tonnage is greater than that of the next 13 largest navies combined. The U.S...
had agreed to purchase her. At the time of her first flight in 1921, she was the world's largest airship. The American designation ZR-2 was already painted on the hull before its four completed test flights and in preparation for a final trial flight and delivery to Lakehurst. On 23 August 1921, ZR-2 was destroyed by a structural failure while in flight over the city of Hull
Kingston upon Hull
Kingston upon Hull , usually referred to as Hull, is a city and unitary authority area in the ceremonial county of the East Riding of Yorkshire, England. It stands on the River Hull at its junction with the Humber estuary, 25 miles inland from the North Sea. Hull has a resident population of...
and crashed into the Humber estuary
Humber
The Humber is a large tidal estuary on the east coast of Northern England. It is formed at Trent Falls, Faxfleet, by the confluence of the tidal River Ouse and the tidal River Trent. From here to the North Sea, it forms part of the boundary between the East Riding of Yorkshire on the north bank...
, killing 44 out of the 49 crew aboard. This disaster resulted in more deaths than the more famous Hindenburg Disaster
Hindenburg disaster
The Hindenburg disaster took place on Thursday, May 6, 1937, as the German passenger airship LZ 129 Hindenburg caught fire and was destroyed during its attempt to dock with its mooring mast at the Lakehurst Naval Air Station, which is located adjacent to the borough of Lakehurst, New Jersey...
that killed 35.
Design and development
The R38 class was designed in response to an Admiralty requirement of June 1918 for an airship capable of six days of patrol, at ranges of up to 300 miles from home base, and at altitudes of up to 22,000 ft. Apart from scouting duties, a heavy load of armament was specified, to allow airship to be used for escort duties for surface vessels. The contract for R38 was awarded to Short BrothersShort Brothers
Short Brothers plc is a British aerospace company, usually referred to simply as Shorts, that is now based in Belfast, Northern Ireland. Founded in 1908, Shorts was the first company in the world to make production aircraft and was a manufacturer of flying boats during the 1920s, 1930s, and 1940s...
, followed by orders for three more ships to the same design. Construction of R38 commenced at Cardington, Bedfordshire
Cardington, Bedfordshire
Cardington is a village and civil parish in the Borough of Bedford in Bedfordshire, EnglandPart of the ancient hundred of Wixamtree, the settlement is best known in connection with the Cardington airship works founded by Short Brothers during World War I, which later became an RAF training station...
in February 1919. Certain modifications to the original design had to be made to allow the R38s to be built within the available construction shed
Airship hangar
Airships are sheltered in airship hangars during construction and sometimes also for regular operation, particularly at bad weather conditions. Rigid airships always needed to be based in airship hangars because weathering was a serious risk.- History :...
. As a result, two of the power cars were moved up to the sides of the structure to save height, the number of gas bags was reduced from 16 to 14 and there were fewer girder rings around the envelope.
Later in 1919, several airship orders were cancelled as a peacetime economy measure, including the three R38 class ships on which work had not yet commenced: R39, R40, and R41. In a further round of cutbacks, the cancellation of the unfinished R38 also appeared imminent, but before this was actually carried out, the project was offered to the United States in October.
The United States Navy
United States Navy
The United States Navy is the naval warfare service branch of the United States Armed Forces and one of the seven uniformed services of the United States. The U.S. Navy is the largest in the world; its battle fleet tonnage is greater than that of the next 13 largest navies combined. The U.S...
had decided that it wanted to add rigid airships to its fleet and originally intended to get some German Zeppelins as part of the wartime reparations but these were deliberately destroyed by their crews in 1919. An order was placed with the Zeppelin company for a new craft (to be paid for by the Germans) and to go with it they planned to build one in the United States. With the news that the R38 had been cancelled the possibility of buying it was investigated. An agreement was reached in October 1919 for purchase at $2,000,000 and work on the airship recommenced. Changes included a requirement for mast mooring gear, which added a ton to the bows which was then balanced by ballast at the rear. This modification along with the weight savings in the design made a craft that was weak longitudinally. The Germans had made lightweight high altitude Zeppelins towards the end of the war and part of one of these, the L 70, had been recovered from the North Sea after it was shot down in August 1918. However it was not realised that the manoeverability of these Zeppelins was deliberately restricted, especially in the rate and tightness of turn, due to the lightweight structure.
Operational history
RNAS Howden
RNAS Howden was an airship station near the town of Howden south-west of York, UK. Opened on 26 June 1916 during the First World War, to cover the East Coast ports shipping from attacks by German U-boats. From 1916 to 1918 Howden was a Royal Naval Air Service establishment...
where the full conversion to American livery was to be made. After some modifications to the rudder and elevators, a second test flight flew on 17 July to Howden for airworthiness and acceptance trials. Some testing of the re-balanced control surfaces was performed on this flight which resulted in severe pitching. When in the shed at Howden, examination of the structure revealed damage to several of the girders. These were replaced and others were strengthened but there were increasing doubts being expressed about the design including some by Air Commodore
Air Commodore
Air commodore is an air-officer rank which originated in and continues to be used by the Royal Air Force...
E. M. Maitland
Edward Maitland (aviator)
Air Commodore Edward Maitland Maitland CMG DSO AFC FRGS was an early military aviator who served in the Air Battalion of the Royal Engineers, the Royal Flying Corps, the Royal Naval Air Service and the Royal Air Force....
, the very experienced commander of the Howden base.
Following a spell of bad weather the airship was finally walked out on 23 August and in the early morning took off for her fourth flight which had an intended destination of RNAS Pulham
RNAS Pulham
RNAS Pulham was an Royal Navy Air Service airship station, south of Norwich, UK. Though land was purchased by the Navy in 1912 the site was not operational until 1915...
, Norfolk where she could be moored to a mast, a facility lacking at Howden. In the event mooring proved impossible because of low cloud and so the airship returned out to sea with the intention of running some high speed tests and then returning to Howden. The speed runs proved successful and as there was still daylight left it was decided to try some low altitude rudder tests to simulate the effects of the rough weather that could be expected on the Atlantic crossing. At 17:37, fifteen degrees of rudder was applied over the city of Hull
Kingston upon Hull
Kingston upon Hull , usually referred to as Hull, is a city and unitary authority area in the ceremonial county of the East Riding of Yorkshire, England. It stands on the River Hull at its junction with the Humber estuary, 25 miles inland from the North Sea. Hull has a resident population of...
. Eye witnesses reported seeing creases down the envelope and then both ends drooped. This was followed by a fire in the bow and then a large explosion which broke windows over a large area. The airship had failed structurally and fell into the shallow waters of the Humber estuary. Sixteen of the 17 Americans and 28 of the 32 Britons in the crew were killed. The only American to survive was Rigger Norman C. Walker. The five who survived were in the tail section. A memorial was erected at Hull, Yorkshire
Yorkshire
Yorkshire is a historic county of northern England and the largest in the United Kingdom. Because of its great size in comparison to other English counties, functions have been increasingly undertaken over time by its subdivisions, which have also been subject to periodic reform...
.
Stress analysis
Stress analysis is an engineering discipline that determines the stress in materials and structures subjected to static or dynamic forces or loads. A stress analysis is required for the study and design of structures, e.g., tunnels, dams, mechanical parts, and structural frames among others, under...
in the design and that while no loads had been placed on the structure during testing that would not have been met in normal use, the effects of the manoeuvres made had weakened the hull. No blame was attached to anyone, this was not part of the committee's remit.