Misplaced Pages

#224775

61-453: Based on the unbuilt Tupolev ANT-36 (DB-1) single-engined bomber, the ANT-37 was a twin-engined monoplane of stressed skin , dural construction, fitted with a high-aspect-ratio wing and tailwheel landing gear, the main units retracting into the engine nacelles. Powered by 800 hp (597 kW) Gnome-Rhône 14K radial engines, the prototype first flew on 16 June 1935. The program suffered

122-421: A Warren or Pratt truss ; in either case, adding discrete diagonal members results in full frame structures in which the skin contributes very little or nothing to the structural rigidity. In a stressed-skin design, the skin or outer covering is bonded or pinned to the frame, adding structural rigidity by serving as the triangulating member which resists distortion of the rectangular structure. The skin provides

183-468: A beam without distress. In the parliamentary process, Stephenson was naturally challenged as to the feasibility of his tubular bridge, but succeeded in convincing sceptical members, and the Chester and Holyhead Railway Act 1845 ( 8 & 9 Vict. c. xxxiii) received royal assent on 30 June 1845. After some experimentation, rectangular tubes (as opposed to circular or elliptical) were decided on, and

244-485: A circular- or egg-shaped cross-section. Experiments with scale models led Fairbairn to suggest a hollow rectangular beam instead, with longitudinal stringers on top and bottom fixed firmly to structural coverings: "two longitudinal plates, divided by vertical plates so as to form squares, calculated to resist the crushing strain in the first instance, and the lower parts [...], also longitudinal plates, well-connected with riveted joints, and of considerable thickness to resist

305-500: A competitor. A significant financial issue was the government mail contract, and there was unsavoury horse trading with senior government representatives. Just before passage of the authorising bill, the directors responded to a government suggestion to operate the railway by atmospheric traction . Robert Stephenson investigated and advised against it, and the idea was dropped. Work started on 1 May 1845. The North Wales Mineral Railway had obtained parliamentary authority to build

366-399: A composite structure. The weakness of cast iron in tension was well understood, and the ties were present to overcome that difficulty. The main beams were formed of three units bolted together end-to-end, and trussed by the wrought iron ties. The track was supported by oak decking timbers laid on the bottom flange of the main beams. On 24 May 1847, one of the spans failed as a passenger train

427-671: A line from a junction with the C&;HR line at Saltney , near Chester, to Ruabon . By late 1846, the NWMR line was ready; the company had amalgamated with the Shrewsbury, Oswestry and Chester Railway to form the Shrewsbury and Chester Railway . Relying on the C&HR for final access to Chester, it requested that company to make the short section into Chester available, and on 4 November 1846 S&CR operation started. The Chester station

488-537: A number of locations south of the C&HR main line, and the C&HR and the LNWR encouraged the building of branch lines to serve them. Llandudno was an early centre of leisure and holiday travel, and in the last decades of the nineteenth century, that traffic became increasingly important. In the twentieth century, the North Wales coast became a popular holiday destination, reached largely by rail travel. In 1970,

549-536: A one-sixth scale model was tested to destruction. This gave Stephenson confidence in the concept, and auxiliary support chains earlier thought necessary were dispensed with. The erection would be performed by hydraulic jacks. A bridge over the River Dee near Chester was already in use. As it was in the section of route used by the Shrewsbury and Chester Railway, trains had been using it since November 1846. It used cast iron beams supported by wrought iron ties in

610-489: A railway network was taking shape. A number of schemes to reach a North Wales port were put forward; the Menai would be crossed using Telford's Menai (road) bridge, hauling coaches and wagons across by ropes. When there was talk of a second, railway, bridge, the poor state of the money market frightened off promoters. In January 1840, the commissioners were still considering the matter, and were given strong advice that Holyhead

671-699: A setback when the prototype crashed the following month, after the tail splintered into pieces during flight. A re-designed second prototype was built, designated as the DB-2D , in an attempt to overcome the design problems encountered during flight testing, particularly with the tail unit. It was decided not to order the type into production, the Ilyushin DB-3 being selected for Soviet Air Force service instead. Despite this, three aircraft were built, designated ANT-37bis (or DB-2B ), for research and record breaking purposes. These three aircraft would survive into

SECTION 10

#1732781132225

732-410: A significant portion of the overall structural rigidity by taking the in-plane shear stress; however, the skin provides very little resistance to out-of-plane loads. These types of structures may also be called semi-monocoque to distinguish them from monocoque designs. There is some overlap between monocoque, semi-monocoque (stressed skin), and rigid frame structures, depending on the proportion of

793-431: A time when actual operation was dependent on the goodwill of the LNWR, and the C&HR forbore to complete the agreement. The Chester and Holyhead Railway Act 1858 ( 21 & 22 Vict. c. cxxx) of 23 July 1858 allowed the financial support of the C&HR by the LNWR and enabled contractual arrangements, but did not require them. Activation of these clauses would allow running powers for competing companies, and

854-517: Is a rigid construction in which the skin or covering takes a portion of the structural load, intermediate between monocoque , in which the skin assumes all or most of the load, and a rigid frame, which has a non-loaded covering. Typically, the main frame has a rectangular structure and is triangulated by the covering; a stressed skin structure has localized compression -taking elements (rectangular frame) and distributed tension -taking elements (skin). A simple framework box with four discrete members

915-540: Is lighter than a full frame structure and not as complex to design as a full monocoque. William Fairbairn documented the development of the Britannia and Conwy tubular bridges for the Chester and Holyhead Railway in 1849; in it, Fairbairn describes how Robert Stephenson enlisted his aid to revise Stephenson's original concepts, which would route rail traffic inside riveted steel tubes, supported by chains, with

976-432: Is not inherently rigid as it will distort from being square under relatively light loads; however, adding one or more diagonal element(s) that take either tension or compression makes it rigid, because the box cannot deviate from right angles without also altering the diagonals. Sometimes the diagonal elements are flexible like wires, which are used to provide tension, or the elements can be rigid to resist compression, as with

1037-454: The Conway and Llanrwst Railway was authorised on 23 July 1860, and opened to the public on 17 June 1863. In 1868, with the growth of tourism, the line was extended to Betws-y-Coed At this time, the slate industry was expanding massively above Betws-y-Coed, at Blaenau Ffestiniog . Although other railway connections existed there, the LNWR decided to extend the branch to reach it. The result was

1098-484: The Irish Sea was difficult because of the poor harbour facilities on both sides, and the road approach to the harbour at Holyhead , Wales was long and difficult. In 1815 Thomas Telford was commissioned to build an improved road between London and Holyhead, and also between Lancashire and Holyhead. The A5 road as it existed in the 1950s shares much of the heritage of Telford's London to Holyhead route. Telford's road

1159-582: The Liverpool and Manchester Railway ) transforming the land journey time on the British side. The Post Office, and the Admiralty , responsible at that time for operating the packet boats, transferred the main part of the traffic to Liverpool. A number of railway schemes were proposed to reach a harbour, many of them with major practical disadvantages. Late in 1836 a commission was appointed to determine

1220-661: The 1940s. The first of the three DB-2B aircraft was given the name Rodina ("Motherland"), and, flown by an all female crew ( Valentina Grizodubova , Polina Osipenko , and Marina Raskova ) between 24 and 25 September 1938, it was used to establish a distance record of 5,908 km (3,671 mi) before ending in an emergency landing. This set a world's record for distance flown by a woman crew. Data from General characteristics Performance Aircraft of comparable role, configuration, and era Related lists Stressed skin In mechanical engineering , stressed skin

1281-735: The Bettws Extension Railway; this involved a long tunnel bored through hard rock at considerable expense, which opened in 1879. After some false starts, a branch railway into Anglesey was authorised: the Anglesey Central Railway was authorised by the Anglesey Central Railway Act 1863 ( 26 & 27 Vict. c. cxxviii) on 13 July 1863. They had approached the LNWR to work their line, but had been rebuffed. A passenger service started from Gaerwen to Llangefni on 12 March 1865, worked by

SECTION 20

#1732781132225

1342-701: The Britannia Tubular Bridge suffered a serious fire, and the line was closed at that point until 1972 when a new structure at the same site was brought into use. The container traffic at Holyhead has ceased, and passenger connections to the Irish ferries are much reduced, but the entire original main line is still in use for passenger traffic, together with the Llandudno branch and the Conwy Valley line to Blaenau Ffestiniog . In 1800 Acts of

1403-414: The C&HR in turn being worked by the LNWR. Freight and passenger traffic between Bangor and Port Dinorwic commenced on 1 March and 10 March 1852 respectively. On 20 August 1853, a branch to Llandudno was authorised by an act of Parliament. At one time Llandudno, or rather Ormes Bay, had been considered as the departure harbour for Dublin, but as stated Holyhead had overtaken that. Tourism would, it

1464-508: The LNWR declined to enter into that, leaving the C&HR still in suspense. The C&HR decided to apply for powers to merge with any other company whatever, and this finally forced the LNWR's hand into full amalgamation. This took effect on 1 January 1859. (The C&HR Company remained in existence until it was dissolved by the London and North-western Railway (Additional Powers) Act 1879 ( 42 & 43 Vict. c. cxlii) of 21 July 1879.) In

1525-462: The LNWR guaranteed 4% on the debentures. However the lease needed parliamentary authorisation, and the GWR made it clear it would demand running powers, which frightened the LNWR off. Now Samuel Peto joined the board and personally funded debenture payments that the C&HR was otherwise unable to meet. He was elected Chairman on 12 February 1851. Peto's impeccable record resulted in renewed confidence in

1586-469: The Menai Bridge were both completed in 1826. As part of the same project, Holyhead Harbour was substantially improved in 1821, and subsequently extended and further improved in 1831 and 1847. Although other routes to Ireland were used (Liverpool in particular), Holyhead was now the obvious, and easiest, port of access. On the Irish side, Howth Harbour, north of Dublin had been used, but increasingly

1647-438: The Menai. The geographical route was now clear enough, but the concept of the bridge design was not. Such a large span lent itself to the idea of a suspension bridge , and Stephenson considered whether the deck of such a structure could be stiffened so as to carry the concentrated loads of a railway train, but decided against it. Any arched design was objected to by the supposed restriction on navigation it might impose. Stephenson

1708-497: The United Kingdom and Irish parliaments determined the union of the two countries; this took effect on 1 January 1801. Prior to that time, the countries had been in personal union, having a shared sovereign but independent governments. There had long been a necessity for convenient communication between London and Dublin , and the union gave further emphasis to the need, specifically for government mails. The sea crossing of

1769-606: The best route, and Charles Blacker Vignoles became the Engineer to the commission. The preliminary findings of the commission were ambiguous and did not result in a clear proposal for a railway. Domestic railways progressed, however, and in September and October 1840 the Chester and Birkenhead Railway and the Chester and Crewe Railway respectively opened. They connected to the Grand Junction Railway, and

1830-399: The company were promised £100,000 by the LNWR, which was desperately needed, but the LNWR realised they had no powers to make such a loan. Bradshaw's Guide for March 1850 shows a brisk passenger service on the line: passengers could leave Kingstown at 19:30 Dublin time (19:55 GMT) and Holyhead at 01:35 by mail train; the time between Llanfair and Bangor was 35 minutes, although the traveller

1891-433: The company's steamers were using it, but the company were forbidden from operating them. This seemed to be put right in the 1848 session, when an act of Parliament of 22 July 1848 authorised the use of steamboats, and also the increased capital to the extent of £250,000. The company had originally intended to operate its trains itself, but on reflection a working arrangement with the LNWR seemed better, and agreement on this

Tupolev ANT-37 - Misplaced Pages Continue

1952-652: The early 1920s. Dr.-Ing Adolf Rohrbach is credited with coining the term "stressed skin" in 1923. By 1940, duralumin sheets had replaced wood and nearly all new designs used monocoque construction. The adoption of stressed-skin construction resulted in improved aircraft speed and range, accomplished by reduced drag through smoother surfaces, elimination of external bracing, and providing internal space for retractable landing gear. Examples include nearly all modern all-metal airplanes , as well as some railway vehicles, buses and motorhomes . The London Transport AEC Routemaster incorporated internal panels riveted to

2013-582: The end of 1846, the company tried to start negotiation with the government and were curtly rebuffed. Moreover, the City of Dublin Steam Packet Company and other private operators objected to the powers to run steamships sought by the company in the 1847 parliamentary session. The situation was exceedingly paradoxical, because the government was financing improvements to the Holyhead harbour, and to

2074-480: The first half of the nineteenth century, Mold was an important commercial centre, with considerable mineral deposits. Businesspeople there sought a railway connection, and the Mold Railway was incorporated on 9 July 1847. It was to run from a junction near Saltney to Mold, with a branch line to Ffrith . The main line of the Mold Railway opened on 14 August 1849; it was worked by the LNWR. In 1852, responsibility

2135-480: The four main tubes by 7 January 1850. On 5 March 1850, Stephenson drove a test train through the completed single-track span of the bridge, and on 18 March 1850 public passenger trains started running. The Chester and Holyhead main line was connected throughout. At a half-yearly shareholders' meeting in March 1850, it was stated that the bridge had cost £674,000, three times Stephenson's estimate. From April 1850 work

2196-426: The frames which took most of the structure's shear load. Automobile unibodies are a form of stressed skin as well, as are some framed buildings which lack diagonal bracing. Chester and Holyhead Railway The Chester and Holyhead Railway was an early railway company conceived to improve transmission of Government dispatches between London and Ireland, as well as ordinary railway objectives. Its construction

2257-513: The line westward from there. The inspectors were informed that the line would be worked by the London and North Western Railway. (By Act of 16 July 1846 the London and Birmingham Railway, the Grand Junction Railway and the Manchester and Birmingham Railway merged to form the London and North Western Railway .) In the 1845 session of Parliament, the company deposited plans for the crossing of

2318-434: The matter to a head. The C&HR would be worked as part of the LNWR system, paying the C&HR shareholders 1% above its own working expenses rate after an initial period. The arrangement was to start on 1 July 1856. Full acquisition of the C&HR was now inevitable, but the C&HR needed to negotiate renewal of the steamer service and the mail contract. The contract would have onerous obligations and heavy penalties at

2379-407: The money markets, and preference shares were suddenly oversubscribed. Nevertheless, it was only in the half-year ending 31 December 1854 that the company made a net profit, and this allowed a small dividend on the first preference shares only. The financial position of the company was one of continuing indebtedness, in fact dependency on the LNWR, and the LNWR decided that the time had come to bring

2440-463: The site from 12 February 1848. On 6 March, the tubes were floated into position ready for raising. By 18 April, Stephenson was able to drive a demonstration train over the bridge. Public traffic over the bridge started on 1 May 1848. The line from Llanfair to Holyhead was opened to public traffic on 1 August 1848. As the Menai crossing was not yet ready, passengers and goods were conveyed across by coach and carts respectively. The Holyhead station

2501-498: The small harbour at Dún Laoghaire south of the city was used; it had been renamed Kingstown in 1821 in honour of a visit by King George IV . The stagecoach transit from London to Holyhead had been 45 hours, and was now cut to 36 hours, and by 1832 to 28 hours. However, in 1838 there was through railway connection from London to Liverpool (over the London and Birmingham Railway , the Grand Junction Railway , and

Tupolev ANT-37 - Misplaced Pages Continue

2562-435: The structural rigidity contributed by the skin. In a monocoque design, the skin assumes all or most of the stress and the structure has fewer discrete framing elements, sometimes including only longitudinal or lateral members. In contrast, a rigid frame structure derives only a minor portion of the overall stiffness from the skin, and the discrete framing elements provide the majority. This stressed skin method of construction

2623-511: The tensile strain in the second". This has been credited as the first instance of stressed skin design, also known as sandwich or double hull . The first aircraft from the early 1900s were constructed with full frames consisting of wood or steel tube frame members, covered with varnished fabric or plywood, although some companies began developing monocoque structures which were built by bending and laminating thin layers of tulipwood . Oswald Short patented an all-metal, stressed-skin wing in

2684-505: The tie bars, transferring nearly all the load to the cast beams alone. A painter had been working on a girder which cracked before the accident, and he actually measured a very large deflection of five and a half inches at the centre of the span when a train was passing. While the parliamentary attention had been on the Menai crossing, the Conwy bridge (at the time spelt Conway) was to be erected first. Stephenson took up temporary residence at

2745-495: The working of the line by an act of Parliament of 1863, and the company was amalgamated with the LNWR by an act of Parliament of 15 July 1867. After the absorption of the Chester and Holyhead Railway by the LNWR in 1859, more branches connecting the line were built: In the mid-nineteenth-century, Llanrwst was an important market town, and a branch to it from the main line had been contemplated for some time. The LNWR promoted

2806-449: Was authorised by the Vale of Clwyd Railway Act 1856 ( 19 & 20 Vict. c. xlv) on 23 June 1856. It was to run from a junction with the C&HR at Foryd Junction, not far from Rhyl, to Denbigh . It opened using a temporary station at Denbigh on 22 September 1858. For the time being the C&HR, shortly to be taken over by the LNWR, allowed access to their Rhyl station. The LNWR took over

2867-454: Was beginning to think of a bridge structure in the form of a straight tube; the unusual depth of the beam would give sufficient bending strength. John Laird , a shipbuilder and C&HR board member, told Stephenson of the case of the launch of a steamship, the Prince of Wales. The launch went astray, and the ship ended up supported on ground at bow and stern, over a length of 180 feet, acting as

2928-652: Was completed from Shrewsbury to Bangor in 1819, and across Anglesey in 1828, including the Stanley Embankment from Anglesey to Holy Island . The London route avoided Conway , crossing the River Conwy at Betws-y-Coed , but the Lancashire route required to cross the river, and both routes needed to cross the Menai Strait . Telford built bridges for these crossings. The Conwy Bridge and

2989-427: Was crossing at 30 miles per hour (48 km/h). Six people were killed. The engine successfully crossed the bridge, but the progressive failure led to the bridge collapsing under the tender and following coaches. The probable cause is nowadays considered to be fatigue tension fracture of the beams, provoked by asymmetric loading by the deck timbers, a stress-raising feature in the profile of the beams, and relaxation of

3050-534: Was hugely expensive, chiefly due to the cost of building the Britannia Tubular Bridge over the Menai Strait . The company had relied on Government support in facilitating the ferry service, and this proved to be uncertain. The company opened its main line throughout in 1850. It relied on the co-operation of other railways to reach London, and in 1859 it was absorbed by the London and North Western Railway . There were extensive mineral deposits at

3111-508: Was more than a mile from the pier, and the line was extended to reach it much later, in 1851. At this period the Company found itself considerably overstretched financially, at a time when the money market was unfavourable to the raising of additional funds. The problem was severe, but was overcome when the London and North Western Railway agreed to take preference shares and contractors were paid in company debentures . The Menai bridge

SECTION 50

#1732781132225

3172-402: Was not informed that this was by road vehicle; the onward journey arrived at Chester at 04:40 and arrival in London was at 13:00. Three other services traversed the whole line, one on Sundays, and two to London and two only on the line respectively on Sundays. The LNWR offered at length an advance of £250,000 to finish the works and lease the railway. The arrangement was to last seven years, and

3233-570: Was opened, although not quite finished, on 1 August 1848. The works on the line were always expected to be difficult, and progress was slow. In 1848, it was decided to open from Chester to Bangor. Captain Wynne of the Board of Trade visited for the required inspection for passenger opening, on 19 and 20 April 1848. He inspected the line as far as the Conway, his colleague Captain J. L. A. Simmons inspected

3294-528: Was reached in August 1847. The government once again dealt harshly with the company over the mail contract, requiring them to take over the Admiralty steamers (even though they knew the company had ordered their own). A sequence of threatened withdrawals of co-operation followed; at the same time the C&HR's financial position deteriorated steeply, and the board seemed to be at loggerheads. In August 1849,

3355-427: Was started on the structure for the second track. The final lift of the last main tube took place on 16 August 1850. On 19 October 1850, trains started using the second track in the bridge, and the full public operation started on 21 August. The directors had always assumed that they would be awarded the mail contract on the opening of the line, and that this would include operating the mail packet boat service. Towards

3416-412: Was the only suitable North Wales harbour, and that a line there from Chester was the best option. Nonetheless, the matter was still not settled, and railway use of the Menai road bridge was still being considered. The prevarication, and suggestions of other routes, continued; but in the 1844 session of Parliament a Chester and Holyhead Railway was proposed. On 4 July 1844 it obtained royal assent. The line

3477-472: Was thought, support the branch. Originally it was intended to join the main line at Conway, facing Holyhead, but it was realised that the available space there prevented that, and the point of junction was placed east of the Conwy river, at what became Llandudno Junction . The branch opened on 1 October 1858. It was worked by the LNWR, and leased to that company in 1862, and vested in the LNWR by an act of Parliament of 28 July 1873. The Vale of Clwyd Railway

3538-462: Was to be 85 miles long; authorised capital was £2.1 million. The approval excluded the crossing of the Menai while allowing the main sections to be started. The London and Birmingham Railway was permitted to subscribe £1 million of the authorised capital. After some hesitation, the L&;BR took up the subscription, apparently motivated by the nascent South Wales Railway , which it feared might be

3599-540: Was to be joint with the Shrewsbury and Chester Railway and the other railways: the Chester and Birkenhead Railway (opened 30 September 1841), the Chester and Crewe Railway (opened 1 October 1840 and already absorbed into the Grand Junction Railway). The station design was modified to be a joint station to accommodate all the traffic. Authorisation of construction of the station was by the Shrewsbury and Chester Railway Act 1847 , of 9 July. The station

3660-452: Was to have two main spans each with twin tubes (for double track), and the tubes were to be 406 feet in length. The central pier was to be 221 feet high. Work started at the site in July 1847, and by November 1848 fabrication of the main tubes was substantially completed. From 19 June 1849 the tubes for one line of track were floated into position and raised by jacks; the process was completed for

3721-522: Was transferred to the C&HR and the LNWR. The line was extended to the Admiralty Pier at Holyhead on 20 May 1851, and a new general station was opened on 14 September 1851. The Bangor and Carnarvon Railway was incorporated by the Bangor and Caernarvon Railway Act 1851 ( 14 & 15 Vict. c. xxi) on 20 May 1851. The line was leased to the Chester and Holyhead Railway from the time of opening,

SECTION 60

#1732781132225
#224775