Angle of incidence (aerodynamics)
On fixed-wing aircraft, the angle of incidence is the angle between the chord line of the wing where the wing is mounted to the fuselage, a reference axis along the fuselage. The angle of incidence is fixed in the design of the aircraft, with rare exceptions, cannot be varied in flight; the term can be applied to horizontal surfaces in general for the angle they make relative the longitudinal axis of the fuselage. The figure to the right shows a side view of an airplane; the extended chord line of the wing root makes an angle with the longitudinal axis of the aircraft. Wings are mounted at a small positive angle of incidence, to allow the fuselage to have a low angle with the airflow in cruising flight. Angles of incidence of about 6° are common on most general aviation designs. Other terms for angle of incidence in this context are rigging angle and rigger's angle of incidence, it should not be confused with the angle of attack, the angle the wing chord presents to the airflow in flight. Note that some ambiguity in this terminology exists, as some engineering texts that focus on the study of airfoils and their medium may use either term when referring to angle of attack
Samuel Hoare, 1st Viscount Templewood
Samuel John Gurney Hoare, 1st Viscount Templewood, more known as Sir Samuel Hoare, was a senior British Conservative politician who served in various Cabinet posts in the Conservative and National governments of the 1920s and 1930s. He was Secretary of State for Air during most of the 1920s; as Secretary of State for India in the early 1930s, he authored the Government of India Act 1935, which granted provincial-level self government to India. He is most famous for serving as Foreign Secretary in 1935, when he authored the Hoare–Laval Pact with French Prime Minister Pierre Laval; this recognised the Italian conquest of Abyssinia and Hoare was forced to resign by the ensuing public outcry. In 1936 he returned to the Cabinet as First Lord of the Admiralty served as Home Secretary from 1937 to 1939 and was again Secretary of State for Air in 1940, he was seen as a leading "appeaser" and his removal from office was a condition of Labour's agreement to serve in a coalition government in May 1940.
He was British ambassador to Spain from 1940 to 1944. Hoare was born in London on 24 February 1880, the eldest son of Sir Samuel Hoare, 1st Baronet, a Conservative MP from a by-election in 1886 until 1906, to whose baronetcy he succeeded in 1915, his family were the Anglo-Irish branch of an old Quaker family, with a long history of involvement in banking. He was a descendant of Samuel Hoare, but the family had abandoned Quakerism in the mid eighteenth century and Hoare was brought up an Anglo-Catholic. Hoare was educated at Harrow School, where he was a classical scholar, New College, Oxford; as an undergraduate he was awarded a blue in rackets and was a member of the Gridiron and Bullingdon Clubs. He studied classics, taking a first in Mods in 1901, before switching to Modern History, graduating with a first class B. A. in 1903. He was awarded his M. A. in 1910. He became Honorary Fellow of New College. On 17 October 1909, he married youngest daughter of The 6th Earl Beauchamp, their marriage was childless.
It was, in the words of R. J. Q. Adams, “not at first a love match” but in time became “a devoted partnership”. Hoare inherited Sidestrand Hall in 1915, his London home was 18 Cadogan Gardens. Hoare was short built and a dapper dresser; as a youth he took up games to bolster his physique, including figure skating. He became a tournament-level tennis player, he was a poor speaker but a good writer. He was cold. In 1905 Hoare's father arranged for him to be secretary to the Colonial Secretary Alfred Lyttelton to gain political experience. Hoare stood unsuccessfully in the 1906 General Election for Parliament at Ipswich, but became a J. P. for the county of Norfolk that year. Hoare entered local politics in March 1907, when he was elected to the London County Council as a member of the Municipal Reform Party representing Brixton, he served as Chairman of the London Fire Brigade Committee. He served on the LCC until 1910. Hoare was elected to the House of Commons at the January 1910 general election as Member of Parliament for Chelsea.
In these early years he was a member of the Anti-Socialist Union. He showed little interest in the two largest issues of the day, House of Lords reform and Irish Home Rule, he joined the Unionist Social Reform Committee. He supported Female Suffrage and public education, he opposed Welsh disestablishment quite strongly. He encouraged colleagues to call him "Sam" at this time, to soften his detached image. Aged 34 at the time, Hoare joined the Army soon after the outbreak of the First World War, he was commissioned into the Norfolk Yeomanry as a temporary lieutenant on 17 October 1914. To his disappointment, he was only a recruiting officer, he was promoted to temporary captain on 24 April 1915. While acting as a recruiting officer he learnt Russian. In 1916, he was recruited by Mansfield Cumming to be the future MI6's liaison officer with the Russian Intelligence service in Petrograd, he soon became head of the British Intelligence Mission to the Russian General Staff with the temporary rank of lieutenant-colonel.
In that post, he reported to the British Government the death of Rasputin and apologised, because of the sensational nature of the event, for having written it in the style of the Daily Mail. In March 1917 he was posted to Rome. In Italy, he met and recruited the former socialist leader Benito Mussolini on behalf of the British overseas intelligence service, known as MI1. Newly published documents show that Britain’s intelligence service helped Mussolini to finance his first forays into Italian politics as a right-wing politician. Hoping to keep Italy on its side in 1917, during the First World War, British intelligence gave Mussolini aged 34 and editor of a right-wing newspaper, £100 a week to keep his propaganda flowing. For his services in the war Hoare was twice mentioned in despatches, appointed Commander of the Order of St Michael and St George in 1917, awarded the Orders of St Anne and St Stanislas of Russia, of St Maurice and St Lazarus of Italy. Hoare was re-elected to Parliament in 1918, but by 1922 he had become disillusioned with David Lloyd George after the Honours scandal and the Chanak Crisis.
He helped organise the backbench revolt at the Carlton Club meeting which brought down Lloyd George's coalition. In Bonar Law’s new Conservative government he w
Science Museum, London
The Science Museum is a major museum on Exhibition Road in South Kensington, London. It was founded in 1857 and today is one of the city's major tourist attractions, attracting 3.3 million visitors annually. Like other publicly funded national museums in the United Kingdom, the Science Museum does not charge visitors for admission. Temporary exhibitions, may incur an admission fee, it is part of the Science Museum Group, having merged with the Museum of Science and Industry in Manchester in 2012. A museum was founded in 1857 under Bennet Woodcroft from the collection of the Royal Society of Arts and surplus items from the Great Exhibition as part of the South Kensington Museum, together with what is now the Victoria and Albert Museum, it included a collection of machinery which became the Museum of Patents in 1858, the Patent Office Museum in 1863. This collection contained many of the most famous exhibits of. In 1883, the contents of the Patent Office Museum were transferred to the South Kensington Museum.
In 1885, the Science Collections were renamed the Science Museum and in 1893 a separate director was appointed. The Art Collections were renamed the Art Museum, which became the Victoria and Albert Museum; when Queen Victoria laid the foundation stone for the new building for the Art Museum, she stipulated that the museum be renamed after herself and her late husband. This was applied to the whole museum, but when that new building opened ten years the title was confined to the Art Collections and the Science Collections had to be divorced from it. On 26 June 1909 the Science Museum, as an independent entity, came into existence; the Science Museum's present quarters, designed by Sir Richard Allison, were opened to the public in stages over the period 1919–28. This building was known as the East Block, construction of which began in 1913 and temporarily halted by World War I; as the name suggests it was intended to be the first building of a much larger project, never realized. However, the Museum buildings were expanded over the following years.
The Science Museum now holds a collection of over 300,000 items, including such famous items as Stephenson's Rocket, Puffing Billy, the first jet engine, a reconstruction of Francis Crick and James Watson's model of DNA, some of the earliest remaining steam engines, a working example of Charles Babbage's Difference engine, the first prototype of the 10,000-year Clock of the Long Now, documentation of the first typewriter. It contains hundreds of interactive exhibits. A recent addition is the IMAX 3D Cinema showing science and nature documentaries, most of them in 3-D, the Wellcome Wing which focuses on digital technology. Entrance has been free since 1 December 2001; the museum houses some of the many objects collected by Henry Wellcome around a medical theme. The fourth floor exhibit is called "Glimpses of Medical History", with reconstructions and dioramas of the history of practised medicine; the fifth floor gallery is called "Science and the Art of Medicine", with exhibits of medical instruments and practices from ancient days and from many countries.
The collection is strong in clinical medicine and public health. The museum is a member of the London Museums of Medicine; the Science Museum has a dedicated library, until the 1960s was Britain's National Library for Science and Technology. It holds runs of periodicals, early books and manuscripts, is used by scholars worldwide, it was, for a number of years, run in conjunction with the Library of Imperial College, but in 2007 the Library was divided over two sites. Histories of science and biographies of scientists were kept at the Imperial College Library in London until February 2014 when the arrangement was terminated, the shelves were cleared and the books and journals shipped out, joining the rest of the collection, which includes original scientific works and archives, in Wroughton, Wiltshire; the Imperial College library catalogue search system now informs searchers that volumes held there are "Available at Science Museum Library Swindon Currently unavailable". A new Research Centre with library facilities is promised for late 2015 but is unlikely to have book stacks nearby.
The Science Museum's medical collections have a global coverage. Strengths include Clinical Medicine and Public Health; the new Wellcome Wing, with its focus on Bioscience, makes the Museum a leading world centre for the presentation of contemporary science to the public. Some 170,000 items which are not on current display are stored at Blythe House in West Kensington. Blythe House houses facilities including a conservation laboratory, a photographic studio, a quarantine area where newly arrived items are examined. In November 2003, the Science Museum opened the Dana Centre; the centre is an urban café annexed to the museum. It was designed by MJP Architects. In October 2007, the Science Museum cancelled a talk by the co-discoverer of the structure of DNA, James D. Watson, because he claimed that IQ test results showed blacks to have lower intelligence than whites; the decision was criticised by some scientists, including Richard Dawkins, as well as supported by other scientists, including Steven Rose.
Around 450,000 young people visit the Science Museum on educational trips or benefit from i
Elevons or tailerons are aircraft control surfaces that combine the functions of the elevator and the aileron, hence the name. They are used on tailless aircraft such as flying wings. An elevon, not part of the main wing, but instead is a separate tail surface, is a stabilator; the word "elevon" is a portmanteau of aileron. Elevons are installed on each side of the aircraft at the trailing edge of the wing; when moved in the same direction they will cause a pitching force to be applied to the airframe. When moved differentially, they will cause a rolling force to be applied; these forces may be applied by appropriate positioning of the elevons e.g. one wing's elevons down and the other wing's elevons down. An aircraft with elevons is controlled as though the pilot still has separate aileron and elevator surfaces at his disposal, controlled by the yoke or stick; the inputs of the two controls are mixed either mechanically or electronically to provide the appropriate position for each elevon. They were used on the Avro Vulcan, Northrop Grumman B-2 Spirit and the Space Shuttle Orbiter.
Several technology research and development efforts exist to integrate the functions of aircraft flight control systems such as ailerons, elevators and flaps into wings to perform the aerodynamic purpose with the advantages of less: mass, drag, inertia and radar cross section for stealth. However, the main drawback is that when the elevons move up in unison to raise the pitch of the aircraft, generating additional lift, they reduce the camber, or downward curvature of the wing. Camber is desirable when generating high levels of lift, so elevons reduce the maximum lift and efficiency of a wing; these may be used in 6th generation fighter aircraft. Two promising approaches are flexible wings, fluidics. In flexible wings, much or all of a wing surface can change shape in flight to deflect air flow; the X-53 Active Aeroelastic Wing is a NASA effort. The Adaptive Compliant Wing is a commercial effort. In fluidics, forces in vehicles occur via circulation control, in which larger more complex mechanical parts are replaced by smaller simpler fluidic systems where larger forces in fluids are diverted by smaller jets or flows of fluid intermittently, to change the direction of vehicles.
In this use, fluidics promises lower mass and low inertia and response times, simplicity. Aileron Flaperon Delta Wing Flying wing Spoileron Stabilator
For the types of transport aircraft called Andover used by the RAF, see Avro Andover and Hawker Siddeley Andover. For the current use of this site see Marlborough Lines. RAF Andover is a former Royal Flying Corps and Royal Air Force station located 2 miles west of Andover, Hampshire and 15.1 miles north east of Salisbury, England. The airfield has a notable place in history, being the site of both the first attempt to develop a viable long-range electronic navigation system, during the First World War, of the first British military helicopter unit and first European helicopter flying training school, during the Second World War. RAF Andover was used before and after the Second World War for a variety of other aeronautical research and flight testing; the RAF Staff College, Andover was founded here in 1922, the first college to train officers in the administrative and policy aspects of running an air force. RAF Andover saw action during the Second World War. Corporal Josephine Robins, one of only six members of the WAAF to win the Military Medal during the War, won her award for courage while rescuing people during an air-raid on the airfield in the Battle of Britain.
Three squadrons of the Royal Canadian Air Force were formed at RAF Andover. Before and during the Battle of Normandy, RAF Andover was used by the United States Army Air Forces Ninth Air Force as an operational tactical fighter airfield, it was known as USAAF Station 406, Pundit Code AV. The code AV was broadcast in morse code by a mobile red light beacon at night, during the latter part of the War; the code was painted on the airfield hangar nearest to the control tower, remained visible until the hangars were demolished in 2001. The site was redeveloped, in 2009 part of it became Marlborough Lines, home to the Headquarters of the British Army; the earliest known human activity on the site of Andover Airfield took place in the Bronze Age, according to archaeological evidence, which has uncovered significant Iron Age and activity, including both an Anglo-Saxon and medieval cemeteries. Military activity on the site is established with the construction during or shortly after 43 AD of the Portway Roman Road from Silchester to Old Sarum, which just north of the Airfield meets at East Anton Crossroads the Roman Road from Winchester to Mildenhall.
The Andover sections of these roads were constructed by the Legio II Augusta Roman Legion. The Royal Flying Corps opened a station near Andover in August 1917 during the First World War; the station was built by German prisoners of war, some of whom left their signatures in roof spaces of buildings on the station. It is close to the Armed Forces Chaplaincy Centre at Amport House and the Army Air Corps Centre at Middle Wallop. Plans for an RFC "Training Depot Station" on the airfield site had been made in 1912; the station motto was Vis et. This is appropriate as the station was built as a Training Depot for aircrews, who had completed basic flying training, to learn to fly the Handley Page Type O and Airco D. H. 9 bombers. The first unit to occupy the station was No. 2 School of Bomb Dropping. This unit took up residence. Amongst squadrons formed at Andover was 106 Squadron, formed on 30 September 1917, who were equipped with Royal Aircraft Factory R. E.8 reconnaissance aircraft for army co-operation duties, being posted to Ireland in May 1918.
From 24 December 1917 to 6 June 1918 Andover was host to a detachment of the 13th Aero Squadron of the Aviation Section, U. S. Signal Corps. In early 1918 experiments were conducted with Handley Page Type O bombers, based at Andover and Cranwell, fitted with Radio Direction-Finding equipment for night flying; the intention was to guide British bombers to and from Berlin, early results led to 550 sets of RDF equipment being ordered by the United States Army Air Service, but the First World War ended before any attempts could be made to use the system operationally. This was the first attempt to develop a viable long-range electronic navigation system, of a kind, today used worldwide. Between the wars, the airfield housed a number of RAF units, including from 1919 the RAF School of Navigation, as No. 2 School of Navigation and Bomb Dropping was retitled. The RAF Staff College was founded here on 1 April 1922, to provide staff training to selected officers, moved to the Bracknell in 1970; the formation of the Royal Air Forces Association followed a conversation in 1929 in the Sergeants’ Mess of RAF Andover.
RAF Andover continued to be used for a variety of aeronautical flight testing. As part of this, several experimental military aircraft made their first flights from the airfield. Amongst them were: the Westland Yeovil. Two experimental bomber squadrons were based at RAF Andover in the late 1920s and early 1930s, No. 12 Squadron RAF and No. 101 Squadron RAF. 12 Squadron was based at RAF Andover from operating Fairey Fawn light bombers. No. 13 Squadron was based here for five years between 1924 and 1929, operating Armstrong Whitworth Atlas aircraft. The Fairey Fox bombers of No. 12 Squadron was one of the two experimental bomber squadrons based on the station, these aircraft being faster than all other contemporary fighters and bombers. To this day, 12 Squadron's official unit motto'Leads the Field' and crest
In aeronautics, a spoiler is a device intended to intentionally reduce the lift component of an airfoil in a controlled way. Most spoilers are plates on the top surface of a wing that can be extended upward into the airflow to spoil it. By so doing, the spoiler creates a controlled stall over the portion of the wing behind it reducing the lift of that wing section. Spoilers differ from airbrakes in that airbrakes are designed to increase drag without affecting lift, while spoilers reduce lift as well as increasing drag. Spoilers fall into two categories: those that are deployed at controlled angles during flight to increase descent rate or control roll, those that are deployed on landing to reduce lift and increase drag. In modern fly-by-wire aircraft, the same set of control surfaces serve both functions. Spoilers are used by nearly every glider to control their rate of descent and thus achieve a controlled landing. An increased rate of descent can be achieved by lowering the nose of an aircraft, but this would result in increased speed.
Spoilers enable the approach to be made at a safe speed for landing. Airliners are always fitted with spoilers. Spoilers are used to increase descent rate without increasing speed, their use is limited, however, as the turbulent airflow that develops behind them causes noise and vibration, which may cause discomfort to passengers. Spoilers may be differentially operated for roll control instead of ailerons. On landing, the spoilers are nearly always deployed to help slow the aircraft; the increase in form drag created by the spoilers directly assists the braking effect. However, the real gain comes as the spoilers cause a dramatic loss of lift and hence the weight of the aircraft is transferred from the wings to the undercarriage, allowing the wheels to be mechanically braked with less tendency to skid. In air-cooled piston engine aircraft, spoilers may be needed to avoid shock cooling the engines. In a descent without spoilers, air speed is increased and the engine will be at low power, producing less heat than normal.
The engine may cool too resulting in stuck valves, cracked cylinders or other problems. Spoilers alleviate the situation by allowing the aircraft to descend at a desired rate while letting the engine run at a power setting that keeps it from cooling too quickly. Spoiler controls can be used for descent control; some aircraft use spoilers in combination with or in lieu of ailerons for roll control to reduce adverse yaw when rudder input is limited by higher speeds. For such spoilers the term spoileron has been coined. In the case of a spoileron, in order for it to be used as a control surface, it is raised on one wing only, thus decreasing lift and increasing drag, causing roll and yaw. Spoilerons avoid the problem of control reversal that affects ailerons. All modern jet airliners are fitted with inboard lift spoilers which are used together during descent to increase the rate of descent and control speed; some aircraft use lift spoilers on landing approach to control descent without changing the aircraft's attitude.
One jet airliner not fitted with lift spoilers was the Douglas DC-8 which used reverse thrust in flight on the two inboard engines to control descent speed. The Lockheed Tristar was fitted with a system called Direct Lift Control using the spoilers on landing approach to control descent. Airbus aircraft with fly-by-wire control utilise wide-span spoilers for descent control, gust alleviation, lift dumpers. On landing approach, the full width of spoilers can be seen controlling the aircraft's descent rate and bank. Lift dumpers are a special type of spoiler extending along much of the wing's length and designed to dump as much lift as possible on landing. Lift dumpers have only two positions and retracted. Lift dumpers have three main functions: putting most of the weight of the aircraft on the wheels for maximum braking effect, increasing form drag, preventing aircraft'bounce' on landing. Lift dumpers are always deployed automatically on touch down; the flight deck control has three positions: off and manual.
On landing approach'automatic' is selected and, at the moment of touchdown, lift dumpers are deployed in a fraction of a second, with flight control spoilers being raised automatically as additional lift dumpers. All modern jet aircraft are fitted with lift dumpers; the British Aerospace 146 is fitted with wide span spoilers to generate additional drag and make reverse thrust unnecessary. A number of accidents have been caused either by inadvertently deploying lift dumpers on landing approach, or forgetting to set them to'automatic'. Air Canada Flight 621 – Premature deployment of the spoilers at low altitude contributed to this crash in Toronto on 5 July 1970. United Airlines Flight 553 – Forgetting to deactivate the spoilers contributed to crash at Chicago Midway International Airport on 8 December 1972. Loftleiðir Icelandic Airlines Flight 509 – Deployment of lift dumpers while attempting to arm them 40 feet above the runway caused this accident at John F Kennedy International Airport on 23 June 1973.
American Airlines Flight 965 – Forgetting to deactivate the spoilers while climbing to avoid a mountain contributed to this crash on 20 December 1995. American Airlines Flight 1420 – Forgetting to deploy the s
A transatlantic flight is the flight of an aircraft across the Atlantic Ocean from Europe, Africa, or the Middle East to North America, Central America, or South America, or vice versa. Such flights have been made by fixed-wing aircraft, airships and other aircraft. Early aircraft engines did not have the reliability needed for the crossing, nor the power to lift the required fuel. There are difficulties navigating over featureless expanses of water for thousands of miles, the weather in the North Atlantic, is unpredictable. Since the middle of the 20th century, transatlantic flight has become routine, for commercial, military and other purposes. Experimental flights present challenges for transatlantic fliers; the idea of transatlantic flight came about with the advent of the balloon. The balloons of the period were inflated with coal gas, a moderate lifting medium compared to hydrogen or helium, but with enough lift to use the winds that would be known as the Jet Stream. In 1859, John Wise built an enormous aerostat named intending to cross the Atlantic.
The flight lasted less than a day, crash-landing in New York. Thaddeus S. C. Lowe prepared a massive balloon of 725,000 cubic feet called the City of New York to take off from Philadelphia in 1860, but was interrupted by the onset of the American Civil War in 1861; the possibility of transatlantic flight by aircraft emerged after the First World War, which had seen tremendous advances in aerial capabilities. In April 1913 the London newspaper The Daily Mail offered a prize of £10,000 to The competition was suspended with the outbreak of war in 1914 but reopened after Armistice was declared in 1918. Between 8 and 31 May 1919, the Curtiss seaplane NC-4 made a crossing of the Atlantic flying from the U. S. to Newfoundland to the Azores, on to mainland Portugal and the UK. The whole journey took 23 days, with six stops along the way. A trail of 53 "station ships" across the Atlantic gave the aircraft points to navigate by; this flight was not eligible for the Daily Mail prize since it took more than 72 consecutive hours and because more than one aircraft was used in the attempt.
With the war over, there were four teams competing to be the first non-stop across the Atlantic. They were Australian pilot Harry Hawker with observer Kenneth Mackenzie-Grieve in a single engine Sopwith Atlantic; each group had to make a rough field for the takeoff. Hawker and Mackenzie-Grieve made the first attempt on 18 May, but engine failure brought them down in the ocean where they were rescued. Raynham and Morgan made an attempt on 18 May but crashed on take off due to the high fuel load; the Handley Page team was in the final stages of testing its aircraft for the flight in June, but the Vickers group was ready earlier. During 14–15 June 1919, the British aviators Alcock and Brown made the first non-stop transatlantic flight. During the War, Alcock resolved to fly the Atlantic, after the war he approached the Vickers engineering and aviation firm at Weybridge, which had considered entering its Vickers Vimy IV twin-engined bomber in the competition but had not yet found a pilot. Alcock's enthusiasm impressed Vickers's team, he was appointed as its pilot.
Work began on converting the Vimy for the long flight, replacing its bomb racks with extra petrol tanks. Shortly afterwards Brown, unemployed, approached Vickers seeking a post and his knowledge of long distance navigation convinced them to take him on as Alcock's navigator. Vickers's team assembled its plane and at around 1:45 p.m. on 14 June, while the Handley Page team was conducting yet another test, the Vickers plane took off from Lester's Field, in St. John's, Newfoundland. Alcock and Brown flew the modified Vickers Vimy, powered by two Rolls-Royce Eagle 360 hp engines, it was not an easy flight, with unexpected fog, a snow storm causing the crewmen to crash into the sea. Their altitude varied between sea level and 12,000 feet and upon takeoff, they carried 865 imperial gallons of fuel, they made landfall in Galway at 8:40 a.m. on 15 June 1919, not far from their intended landing place, after less than sixteen hours of flying. The Secretary of State for Air, Winston Churchill, presented Alcock and Brown with the Daily Mail prize for the first crossing of the Atlantic Ocean in "less than 72 consecutive hours".
There was a small amount of mail carried on the flight making it the first transatlantic airmail flight. The two aviators were awarded the honour of Knight Commander of the Most Excellent Order of the British Empire one week by King George V at Windsor Castle; the first transatlantic flight by rigid airship, the first return transatlantic flight, was made just a couple of weeks after the transatlantic flight of Alcock and Brown, on 2 July 1919. Major George Herbert Scott of the Royal Air Force flew the airship R34 with his crew and passengers from RAF East Fortune, Scotland to Mineola, New York, covering a distance of about 3,000 miles in about four and a half days; the flight was intended as a testing ground for postwar commercial services by airship, it was the first flight to transport paying passengers. The R34 wasn't built as a passenger carrier, so extra accommodations was arranged by slinging hammocks in the keel walkway; the return journey to Pulham in Norfolk