1.
RPO ZR2
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Regular Production Option ZR2 is a special off-road/suspension package offered by General Motors primarily on their 4x4 Chevrolet S-10 S-Series line. It debuted in 1994 on the Chevrolet S-10 and the GMC Sonoma pickup trucks, in 1996 it was expanded to the two-door Chevrolet S-10 Blazer and later offered on the Chevrolet Tracker. The ZR2 package was gradually phased out with the S-Series pickup, however, it has made a comeback as an option on the 2017 Chevrolet Colorado. Third door was offered on extended cab models,1998 - Disc brakes are now standard on the front and rear wheels. Interior updated along with front grille and headlights,1999 - GM replaces the aluminum skid plates with composite skid plates. Last model year the ZR2 option was offered on a regular-cab pickup and this is the last year that the ZR2 is available on a pickup. A GMC Jimmy ZR2 surfaces in Canada, the Jimmy ZR2 was unavailable in the USA. 2004 - ZR2 available on Blazer and Tracker models, for the first time, the ZR2 is offered in 2WD. 2005 - This is the last year for the ZR2 Blazer, 2016- GM reintroduces the ZR2 option on the Chevrolet Colorado starting on 2017 models. The Zr2. com Archive, The best online resource for all things ZR2, zedR2. com, Does not exist Synergy Offroad, A ZR2-based off-road parts retailer. Diversified Creations, An off-road shop specializing in ZR2 aftermarket support, creator of the SFA ZR2 kit. OutfitterDesign LLC, A manufacturer of specialty ZR2-only off-road component, creator of the Patent-Pending One-Ton Idler Arm Adapter
2.
Short Brothers
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Short Brothers plc, usually referred to as Shorts or Short, is an aerospace company based in Belfast, Northern Ireland. Shorts was founded in 1908 in London, and was the first company in the world to make production aircraft and it was particularly notable for its flying boat designs manufactured into the 1950s. In 1943 Shorts was nationalised and later denationalised, and in 1948 moved from its base at Rochester. In the 1960s, Shorts mainly produced turboprop airliners, major components for aerospace primary manufacturers, in 1989 Shorts was bought by Bombardier, and is today the largest manufacturing concern in Northern Ireland. Prior to that merger, the capital share by the owner was, HM Government,69. 5% Rolls-Royce Ltd,15. 25%. The Short Brothers business started in 1897 when Eustace Short bought a coal gas filled balloon. In 1900 the two visited the 1900 Paris Exposition, where they saw the balloons of Édouard Surcouf. In 1902 Eustace and Oswald started offering balloons for sale and they manufactured the balloons at Hove, Sussex, in premises above the acoustic laboratory run by a third brother, Horace Short. Horace had invented an acoustic amplifier, and was working to perfect it with Thomas Edisons European agent, in 1905 they won a contract for three balloons for the British Indian Army. The quality of their work impressed Colonel Templer, superintendent of the Royal Balloon Factory, Rolls commissioned them to build him a large balloon to compete in the 1906 Gordon Bennett balloon race. More orders soon followed from members of the Aero Club of Great Britain. Oswald succeeded in persuading Horace to leave his job with Parsons, at the end of 1908 Horace started work on the two designs, and in early 1909 construction was started of McCleans aircraft, the Short No.1 biplane. In March 1909 it was exhibited, without its fabric covering, meanwhile, the brothers had obtained the British rights to build copies of the Wright design. In February 1909 Shorts started construction of a new workshop on unobstructed marshland at Leysdown and this had been acquired by the Aero Club for use as a flying ground, together with Mussell Manor, which became its clubhouse. Construction of a batch of six aircraft was started immediately. Short Brothers thus became the first aircraft manufacturing company in the world to undertake production of an aircraft design. In 1910 the business, together with the Royal Aero Club, moved to premises at Eastchurch. Here the Short-Dunne 5, designed by John W. Dunne, was built, in 1911 Shorts built one of the worlds first successful twin-engine aircraft, the Triple Twin
3.
Rigid airship
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Rigid airships are often commonly called Zeppelins, though this technically refers only to airships built by the Luftschifbau Zeppelin company. Rigid airships were produced and relatively successfully employed from the beginning of the 1900s to the end of the 1930s, Rigid airships consist of a structural framework usually covered in doped fabric containing a number of gasbags or cells containing a lifting gas. The noble gas helium was used by American airships in the 1920s and 30s and is used in all modern airships, similarly, by flying nose-down down-force can be generated, this may be done to prevent the airship rising above its pressure height. Typically airships start a flight with their gasbags inflated to about 95% capacity, by 1874 several people had conceived of a rigid dirigible. The Frenchman Joseph Spiess had patented a rigid airship design in 1873, Count Zeppelin had outlined his thoughts of a rigid airship in diary entries from 25 March 1874 through to 1890 when he resigned from the military. David Schwarz had thought about building an airship in the 1880s and had started design work in 1891. It was not until after Schwarzs death in 1897 that his airship, built with help from the industrialist Carl Berg. With Bergs aluminium, Zeppelin was able to start building his first airship in 1899, ferdinand von Zeppelin completed his first airship, the LZ1 in July 1900. Constructed in a shed on Lake Constance, it was 128.02 m long,11.73 m in diameter with a volume of 11,298 m3 and was powered by two 11 kW Daimler engines. The first flight, lasting 20 minutes, was made on 2 July, after repairs and modifications two further flights were made in October 1900. These experiments failed to attract any investors, and Count Zeppelin did not complete his design, LZ2. This made only a flight on 17 January 1906. After both engines failed it made a landing in the Allgäu mountains, where a storm subsequently damaged it beyond repair. A similar design, the LZ3 was soon completed and this performed well enough to interest the German Army, but they required an airship capable of flying for 24 hours. This was beyond the capability of LZ3, so a larger craft and this was 136 m long,12.95 m in diameter and powered by two Daimler engines delivering a total of 156 kW. LZ4 first flew on 20 June 1908, and on 1 July made a spectacular 12 hour cross-country flight during which it was flown over Switzerland to Zürich, the 24-hour trial was started on 4 August, but was interrupted by the failure of one of the engines. It was moored near Echterdingen in order to make repairs but a storm arose and it away from its moorings, was blown into some trees. The disaster took place in front of an estimated 40 to 50 thousand spectators, seven were operated by DELAG, the first airline in the world
4.
Royal Navy
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The Royal Navy is the United Kingdoms naval warfare force. Although warships were used by the English kings from the medieval period. The modern Royal Navy traces its origins to the early 16th century, from the middle decades of the 17th century and through the 18th century, the Royal Navy vied with the Dutch Navy and later with the French Navy for maritime supremacy. From the mid 18th century it was the worlds most powerful navy until surpassed by the United States Navy during the Second World War. The Royal Navy played a key part in establishing the British Empire as the world power during the 19th. Due to this historical prominence, it is common, even among non-Britons, following World War I, the Royal Navy was significantly reduced in size, although at the onset of the Second World War it was still the worlds largest. By the end of the war, however, the United States Navy had emerged as the worlds largest, during the Cold War, the Royal Navy transformed into a primarily anti-submarine force, hunting for Soviet submarines, mostly active in the GIUK gap. The Royal Navy is part of Her Majestys Naval Service, which includes the Royal Marines. The professional head of the Naval Service is the First Sea Lord, the Defence Council delegates management of the Naval Service to the Admiralty Board, chaired by the Secretary of State for Defence. The strength of the fleet of the Kingdom of England was an important element in the power in the 10th century. English naval power declined as a result of the Norman conquest. Medieval fleets, in England as elsewhere, were almost entirely composed of merchant ships enlisted into service in time of war. Englands naval organisation was haphazard and the mobilisation of fleets when war broke out was slow, early in the war French plans for an invasion of England failed when Edward III of England destroyed the French fleet in the Battle of Sluys in 1340. Major fighting was confined to French soil and Englands naval capabilities sufficed to transport armies and supplies safely to their continental destinations. Such raids halted finally only with the occupation of northern France by Henry V. Henry VII deserves a large share of credit in the establishment of a standing navy and he embarked on a program of building ships larger than heretofore. He also invested in dockyards, and commissioned the oldest surviving dry dock in 1495 at Portsmouth, a standing Navy Royal, with its own secretariat, dockyards and a permanent core of purpose-built warships, emerged during the reign of Henry VIII. Under Elizabeth I England became involved in a war with Spain, the new regimes introduction of Navigation Acts, providing that all merchant shipping to and from England or her colonies should be carried out by English ships, led to war with the Dutch Republic. In the early stages of this First Anglo-Dutch War, the superiority of the large, heavily armed English ships was offset by superior Dutch tactical organisation and the fighting was inconclusive
5.
World War I
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World War I, also known as the First World War, the Great War, or the War to End All Wars, was a global war originating in Europe that lasted from 28 July 1914 to 11 November 1918. More than 70 million military personnel, including 60 million Europeans, were mobilised in one of the largest wars in history and it was one of the deadliest conflicts in history, and paved the way for major political changes, including revolutions in many of the nations involved. The war drew in all the worlds great powers, assembled in two opposing alliances, the Allies versus the Central Powers of Germany and Austria-Hungary. These alliances were reorganised and expanded as more nations entered the war, Italy, Japan, the trigger for the war was the assassination of Archduke Franz Ferdinand of Austria, heir to the throne of Austria-Hungary, by Yugoslav nationalist Gavrilo Princip in Sarajevo on 28 June 1914. This set off a crisis when Austria-Hungary delivered an ultimatum to the Kingdom of Serbia. Within weeks, the powers were at war and the conflict soon spread around the world. On 25 July Russia began mobilisation and on 28 July, the Austro-Hungarians declared war on Serbia, Germany presented an ultimatum to Russia to demobilise, and when this was refused, declared war on Russia on 1 August. Germany then invaded neutral Belgium and Luxembourg before moving towards France, after the German march on Paris was halted, what became known as the Western Front settled into a battle of attrition, with a trench line that changed little until 1917. On the Eastern Front, the Russian army was successful against the Austro-Hungarians, in November 1914, the Ottoman Empire joined the Central Powers, opening fronts in the Caucasus, Mesopotamia and the Sinai. In 1915, Italy joined the Allies and Bulgaria joined the Central Powers, Romania joined the Allies in 1916, after a stunning German offensive along the Western Front in the spring of 1918, the Allies rallied and drove back the Germans in a series of successful offensives. By the end of the war or soon after, the German Empire, Russian Empire, Austro-Hungarian Empire, national borders were redrawn, with several independent nations restored or created, and Germanys colonies were parceled out among the victors. During the Paris Peace Conference of 1919, the Big Four imposed their terms in a series of treaties, the League of Nations was formed with the aim of preventing any repetition of such a conflict. This effort failed, and economic depression, renewed nationalism, weakened successor states, and feelings of humiliation eventually contributed to World War II. From the time of its start until the approach of World War II, at the time, it was also sometimes called the war to end war or the war to end all wars due to its then-unparalleled scale and devastation. In Canada, Macleans magazine in October 1914 wrote, Some wars name themselves, during the interwar period, the war was most often called the World War and the Great War in English-speaking countries. Will become the first world war in the sense of the word. These began in 1815, with the Holy Alliance between Prussia, Russia, and Austria, when Germany was united in 1871, Prussia became part of the new German nation. Soon after, in October 1873, German Chancellor Otto von Bismarck negotiated the League of the Three Emperors between the monarchs of Austria-Hungary, Russia and Germany
6.
North Sea
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The North Sea is a marginal sea of the Atlantic Ocean located between Great Britain, Scandinavia, Germany, the Netherlands, Belgium, and France. An epeiric sea on the European continental shelf, it connects to the ocean through the English Channel in the south and it is more than 970 kilometres long and 580 kilometres wide, with an area of around 570,000 square kilometres. The North Sea has long been the site of important European shipping lanes as well as a major fishery, the North Sea was the centre of the Vikings rise. Subsequently, the Hanseatic League, the Netherlands, and the British each sought to dominate the North Sea and thus the access to the markets, as Germanys only outlet to the ocean, the North Sea continued to be strategically important through both World Wars. The coast of the North Sea presents a diversity of geological and geographical features, in the north, deep fjords and sheer cliffs mark the Norwegian and Scottish coastlines, whereas in the south it consists primarily of sandy beaches and wide mudflats. Due to the population, heavy industrialization, and intense use of the sea and area surrounding it. 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. In the north it is bordered by the Shetland Islands, and connects with the Norwegian Sea, the North Sea is more than 970 kilometres long and 580 kilometres wide, with an area of 570,000 square kilometres and a volume of 54,000 cubic kilometres. Around the edges of the North Sea are sizeable islands and archipelagos, including Shetland, Orkney, the North Sea receives freshwater from a number of European continental watersheds, as well as the British Isles. A large part of the European drainage basin empties into the North Sea including water from the Baltic Sea, the largest and most important rivers flowing into the North Sea are the Elbe and the Rhine – Meuse watershed. Around 185 million people live in the catchment area of the rivers discharging into the North Sea encompassing some highly industrialized areas, for the most part, the sea lies on the European continental shelf with a mean depth of 90 metres. The only exception is the Norwegian trench, which extends parallel to the Norwegian shoreline from Oslo to a north of Bergen. It is between 20 and 30 kilometres wide and has a depth of 725 metres. The Dogger Bank, a vast moraine, or accumulation of unconsolidated glacial debris and this feature has produced the finest fishing location of the North Sea. The Long Forties and the Broad Fourteens are large areas with uniform depth in fathoms. These great banks and others make the North Sea particularly hazardous to navigate, the Devils Hole lies 200 miles east of Dundee, Scotland. The feature is a series of trenches between 20 and 30 kilometres long,1 and 2 kilometres wide and up to 230 metres deep. Other areas which are less deep are Cleaver Bank, Fisher Bank, the International Hydrographic Organization defines the limits of the North Sea as follows, On the Southwest
7.
Airship
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An airship or dirigible balloon is a type of aerostat or lighter-than-air aircraft that can navigate through the air under its own power. Aerostats gain their lift from large gas bags filled with a gas that is less dense than the surrounding air. In early dirigibles, the gas used was hydrogen, due to its high lifting capacity. Helium gas has almost the same lifting capacity and is not flammable, unlike hydrogen, significant amounts were first discovered in the United States and for a while helium was only used for airships by the United States. Most airships built since the 1960s have used helium, though some have used hot air, the envelope of an airship may form a single gas bag, or may contain a number of internal gas-filled cells. An airship also has engines, crew, and optionally also payload accommodation, the main types of airship are non-rigid, semi-rigid, and rigid. Non-rigid airships, often called blimps, rely on internal pressure to maintain the shape of the airship, semi-rigid airships maintain the envelope shape by internal pressure, but have some form of supporting structure, such as a fixed keel, attached to it. Rigid airships have a structural framework which maintains the shape and carries all structural loads. Rigid airships were first flown by Count Zeppelin and the vast majority of rigid airships built were manufactured by the firm he founded, as a result, rigid airships are called zeppelins. S. Navy helium-filled rigids, the USS Akron and USS Macon respectively, during the pioneer years of aeronautics, terms such as airship, air-ship, air ship and ship of the air meant any kind of navigable or dirigible flying machine. In 1919 Frederick Handley Page was reported as referring to ships of the air, in the 1930s, large intercontinental flying boats were also sometimes referred to as ships of the air or flying-ships. Nowadays the term airship is used only for powered, dirigible balloons, semirigid architecture is the more recent and the late appearance is caused by both advancements about deformable structures and exigiency of reducing weight and volume of the airships. They have a structure that ensure to keep the shape jointly with overpressure of the gas envelope. An aerostat is an aircraft which remain aloft using buoyancy or static lift, Airships are a type of aerostat. The term aerostat has also used to indicate a tethered or moored balloon as opposed to a free-floating balloon. A blimp is a non-rigid aerostat, in American usage it refers specifically to a non-rigid type of dirigible balloon or airship. In British usage it refers to any non-rigid aerostat, including balloons and other kite balloons, having a streamlined shape. The initials LZ, for Luftschiff Zeppelin, usually prefixed their crafts serial identifiers, streamlined Parsifal-shaped rigid airships are usually referred to as Zeppelin, because of the fame that this company has acquired due to the number of airships it produced
8.
Admiralty
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The new Admiralty Board meets only twice a year, and the day-to-day running of the Royal Navy is controlled by a Navy Board. It is common for the authorities now in charge of the Royal Navy to be referred to as simply The Admiralty. The title of Lord High Admiral of the United Kingdom was vested in the monarch from 1964 to 2011, the title was awarded to Philip, Duke of Edinburgh by Queen Elizabeth II on his 90th birthday. There also continues to be a Vice-Admiral of the United Kingdom, the office of Admiral of England was created around 1400 although there had already been Admirals of the Northern and Western Seas. In 1546, King Henry VIII established the Council of the Marine, later to become the Navy Board, operational control of the Royal Navy remained the responsibility of the Lord High Admiral, who was one of the nine Great Officers of State. In 1628, Charles I put the office of Lord High Admiral into commission, the office of Lord High Admiral passed a number of times in and out of commission until 1709 after which the office was almost permanently in commission. In 1831, the first Navy Board was abolished as a separate entity, in 1964, the Admiralty along with the War Office and the Air Ministry as separate departments of state were abolished, and re-emerged under one single new Ministry of Defence. Within the expanded Ministry of Defence are the new Admiralty Board which has a separate Navy Board responsible for the running of the Royal Navy. The Army Board and the Air Force Board, each headed by the Secretary of State for Defence, the Board of Admiralty consisted of a number of Lords Commissioners of the Admiralty. The Lords Commissioners were always a mixture of admirals, known as Naval Lords or Sea Lords and Civil Lords, the quorum of the Board was two commissioners and a secretary. The president of the Board was known as the First Lord of the Admiralty, after 1806, the First Lord of the Admiralty was always a civilian while the professional head of the navy came to be known as the First Sea Lord. The first real concerted effort to organise the Admiralty was started by Henry VIII. Between 1860 and 1908 there was no study of strategy and of staff work conducted within the naval service. All the navys talent flowed to the great technical universitys and it was perceived by officials within the Admiralty at this time that the running of war was quite a simple matter for any flag officer who required no formal training. The new War Staff had hardly found its feet and it struggled with the opposition to its existence by senior officers they were categorically opposed to a staff. The deficiencies of the system within this department of state could be seen in the conduct of the Dardanelles campaign, there was no mechanisms in place to answer the big strategic questions in 1914 a Trade Division was created. In 1916, Sir John Jellicoe came to the Admiralty, he organized the staff as following, Chief of War Staff, Operations, Intelligence, Signal Section, Mobilization, Trade. This for the first time gave the naval staff direct representation on the Board, the would direct all operations and movements of the fleet, while the would be responsible for mercantile movements and anti-submarine operations
9.
Armistice of 11 November 1918
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It went into effect at 11 a. m. Paris time on 11 November 1918, and marked a victory for the Allies, the Germans were responding to the policies proposed by U. S. President Woodrow Wilson in his Fourteen Points of January 1918. Although the armistice ended the fighting, it took six months of negotiations at the Paris Peace Conference to conclude the peace treaty. In addition, he recommended the acceptance of the demands of US president Woodrow Wilson including putting the Imperial Government on a democratic footing, hoping for more favorable peace terms. As he said to officers of his staff on 1 October, on 3 October, the liberal Prince Maximilian of Baden was appointed Chancellor of Germany, replacing Georg von Hertling in order to negotiate an armistice. In the subsequent two exchanges, Wilsons allusions failed to convey the idea that the Kaisers abdication was a condition for peace. The leading statesmen of the Reich were not yet ready to contemplate such a monstrous possibility, in late October, Ludendorff, in a sudden change of mind, declared the conditions of the Allies unacceptable. He now demanded to resume the war which he himself had declared lost only one month earlier, however the German soldiers were pressing to get home. It was scarcely possible to arouse their readiness for battle anew, the Imperial Government stayed on course and Ludendorff was replaced by Wilhelm Groener. On 5 November, the Allies agreed to take up negotiations for a truce, the latest note from Wilson was received in Berlin on 6 November. That same day, the led by Matthias Erzberger departed for France. For example, they assumed that the de-militarization suggested by Wilson would be limited to the Central Powers, there were also contradictions with their post-War plans that did not include a consistent implementation of the ideal of national self-determination. Also on 9 November, Max von Baden handed over the office of Chancellor to Friedrich Ebert, eberts SPD and Erzbergers Catholic Centre Party had enjoyed an uneasy relationship with the Imperial government since Bismarcks era in the 1870s and 1880s. They were well represented in the Imperial Reichstag, which had power over the government. Their prominence in the negotiations would cause the new Weimar Republic to lack legitimacy in right-wing. The Armistice was the result of a hurried and desperate process and they were then entrained and taken to the secret destination, aboard Ferdinand Fochs private train parked in a railway siding in the forest of Compiègne. Foch appeared only twice in the three days of negotiations, on the first day, to ask the German delegation what they wanted, the Germans were handed the list of Allied demands and given 72 hours to agree. The German delegation discussed the Allied terms not with Foch, but with other French, the Armistice amounted to complete German demilitarization, with few promises made by the Allies in return
10.
Kingston upon Hull
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Kingston upon Hull, usually abbreviated to Hull, is a city and unitary authority in the East Riding of Yorkshire, England. It lies upon the River Hull at its confluence with the Humber estuary,25 miles inland from the North Sea, the town of Hull was founded late in the 12th century. The monks of Meaux Abbey needed a port where the wool from their estates could be exported and they chose a place at the confluence of the rivers Hull and Humber to build a quay. The exact year the town was founded is not known but it was first mentioned in 1193, renamed Kings-town upon Hull by King Edward I in 1299, Hull has been a market town, military supply port, trading hub, fishing and whaling centre, and industrial metropolis. Hull was a theatre of battle in the English Civil Wars. Its 18th-century Member of Parliament, William Wilberforce, took a prominent part in the abolition of the trade in Britain. The city is unique in the UK in having had a municipally owned telephone system from 1902, sporting cream, not red, telephone boxes. After suffering heavy damage in the Second World War, Hull weathered a period of decline, gaining unfavourable results on measures of social deprivation, education. In the early 21st-century spending boom before the late 2000s recession the city saw large amounts of new retail, commercial, housing, tourist attractions include the historic Old Town and Museum Quarter, Hull Marina and The Deep, a city landmark. The redevelopment of one of Hulls main thoroughfares, Ferensway, included the opening of St Stephens Hull, spectator sports include Premier League football and Super League Rugby. The KCOM Stadium houses Hull City football club and Hull F. C. rugby club, Hull is also home to the English Premier Ice Hockey League Hull Pirates. The University of Hull was founded in 1927 and now more than 16,000 students. It is ranked among the best in the Yorkshire and the Humber region and located in the leafy Newland suburb, in 2013, it was announced that Hull would be the 2017 UK City of Culture. In 2015 it was announced that the Ferens Art Gallery will be hosting the annual art prize, The Turner Prize. The prize is held outside London every other year, Kingston upon Hull stands on the north bank of the Humber estuary at the mouth of its tributary, the River Hull. The valley of the River Hull has been inhabited since the early Neolithic period, the area was attractive to people because it gave access to a prosperous hinterland and navigable rivers but the site was poor, being remote, low-lying and with no fresh water. It was originally a part of the hamlet of Myton. The name is thought to either from a Scandinavian word Vik meaning inlet or from the Saxon Wic meaning dwelling place or refuge
11.
R101
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It was designed and built by an Air Ministry-appointed team and was effectively in competition with the government-funded but privately designed and built R100. When built it was the worlds largest flying craft at 731 ft in length, among the deceased passengers were Lord Thomson, the Air Minister who had initiated the programme, senior government officials, and almost all the dirigibles designers from the Royal Airship Works. The crash of R101 effectively ended British airship development, and was one of the worst airship accidents of the 1930s and this led to the nicknames the Socialist Airship and the Capitalist Airship. These called for airships of not less than five million cubic feet capacity, with the necessary allowance of about 20 tons for the service load consisting of a crew of approximately 40, stores and water ballast this meant a possible fuel and passenger load of 42 tons. Accommodation for 100 passengers and tankage for 57 hours flight was to be provided, in wartime, the airships would be expected to carry 200 troops or possibly five parasite fighter aircraft. Vickers design team was led by Barnes Wallis, who had experience of rigid airship design and later became famous for the geodetic framework of the Wellington bomber. Shute later admitted that many of his criticisms of the R101 team were unjustified, in fact, the extensive experimentation that was carried out delayed the start of production of R101 until early 1927. R100 was also delayed, and neither flew until late 1929, the whole airship programme was under the direction of the Director of Airship Development, Group Captain Peregrine Fellowes, with Colmore acting as his deputy. H. Scott, who had developed the design of the masts that were to be built. It had been nationalised in 1919 but after the loss of the R38 naval airship development was stopped and it had placed on a care. R101 was to be only after an extensive research and test programme was complete. This was carried out by the National Physical Laboratory, as part of this programme, the Air Ministry funded the costs of refurbishing and flying R33 in order to gather data about structural loads and the airflow around a large airship. This data was made available to Vickers, both airships had the same elongated tear-drop shape, unlike previous airship designs. This shape had been found to produce the amount of drag. Safety was a concern and this would have an important influence on the choice of engines. An early decision had made to construct the primary structure largely from stainless steel rather than lightweight alloys such as duralumin. Working to a design prepared with the help of data supplied by the NPL. This information was supplied to J. D. North and his team at Boulton and Paul
12.
USS Akron (ZRS-4)
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USS Akron was a helium-filled rigid airship of the U. S. Navy which operated between September 1931 and April 1933. She was the worlds first purpose-built flying aircraft carrier, carrying F9C Sparrowhawk fighter planes which could be launched and recovered while she was in flight, with an overall length of 785 ft, the Akron and her sister ship the Macon were among the largest flying objects ever built. The Akron was destroyed in a thunderstorm off the coast of New Jersey on the morning of 4 April 1933, killing 73 of the 76 crewmen and this accident involved the greatest loss of life in any airship crash. The airships skeleton was built of the new lightweight alloy duralumin 17-SRT, the frame introduced several novel features compared with traditional Zeppelin designs. Rather than being single-girder diamond trusses with radial wire bracing, the rings of the Akron were self-supporting deep frames. The inherent strength of these frames allowed Chief Designer, Dr Karl Arnstein, instead, the fins of the Akron were cantilevered, mounted entirely externally to the main structure. Each keel provided a walkway running almost the length of the ship. The main rings were spaced at 22.5 m and between each pair were three intermediate rings of lighter construction, in keeping with conventional practice, station numbers on the airship were measured in meters from zero at the rudder post, positive forward and negative aft. Thus the tip of the tail was at station -23.75, each ring frame formed a polygon with 36 corners and these were numbered from 1 to 18 port and starboard. Thus a position on the hull could be referred to, for example, while Germany, France and Britain used goldbeaters skin to gas-proof their gasbags, the Akron used Goodyear Tire and Rubbers rubberised cotton, heavier but much cheaper and more durable. Half the gas cells used an experimental cotton-based fabric impregnated with a gelatin-latex compound and this was more expensive than the rubberised cotton but lighter than goldbeaters skin. It was so successful all the gasbags of the Macon were made from it. There were 12 gas cells, numbered 0 to XI, using Roman numerals, while the air volume of the hull was 7,401,260 cu ft, the total volume of the gas cells at 100 percent fill was 6,850,000 cu ft. At a normal 95 percent fill with helium of standard purity, each engine turned a two-bladed,16 ft 4 in diameter, fixed pitch, wooden propeller via a driveshaft and bevel gearing which allowed the propeller to swivel from the vertical plane to the horizontal. With the engines ability to reverse, this allowed thrust to be applied forward, aft and it appears from photographs that the four propellers on each side were contra-rotating, each one turning the opposite way to the one ahead of it. Thus it would appear that the designers were aware that running the propellers in the air disturbed by the one ahead was not ideal and this was to prove problematical in service, inducing considerable vibration, especially noticeable in the emergency control position in the lower fin. By 1933, the Akron had two of her propellers replaced by advanced, ground-adjustable, three-bladed, metal propellers. These promised an increase and were adopted as standard for the Macon
