[{"@context":"http:\/\/schema.org\/","@type":"BlogPosting","@id":"https:\/\/wiki.edu.vn\/en\/wiki24\/armstrong-siddeley-sapphire-wikipedia\/#BlogPosting","mainEntityOfPage":"https:\/\/wiki.edu.vn\/en\/wiki24\/armstrong-siddeley-sapphire-wikipedia\/","headline":"Armstrong Siddeley Sapphire – Wikipedia","name":"Armstrong Siddeley Sapphire – Wikipedia","description":"1940s British turbojet aircraft engine The Armstrong Siddeley Sapphire is a British turbojet engine that was produced by Armstrong Siddeley","datePublished":"2021-01-03","dateModified":"2021-01-03","author":{"@type":"Person","@id":"https:\/\/wiki.edu.vn\/en\/wiki24\/author\/lordneo\/#Person","name":"lordneo","url":"https:\/\/wiki.edu.vn\/en\/wiki24\/author\/lordneo\/","image":{"@type":"ImageObject","@id":"https:\/\/secure.gravatar.com\/avatar\/c9645c498c9701c88b89b8537773dd7c?s=96&d=mm&r=g","url":"https:\/\/secure.gravatar.com\/avatar\/c9645c498c9701c88b89b8537773dd7c?s=96&d=mm&r=g","height":96,"width":96}},"publisher":{"@type":"Organization","name":"Enzyklop\u00e4die","logo":{"@type":"ImageObject","@id":"https:\/\/wiki.edu.vn\/wiki4\/wp-content\/uploads\/2023\/08\/download.jpg","url":"https:\/\/wiki.edu.vn\/wiki4\/wp-content\/uploads\/2023\/08\/download.jpg","width":600,"height":60}},"image":{"@type":"ImageObject","@id":"https:\/\/wiki.edu.vn\/wiki4\/wp-content\/uploads\/2023\/08\/download.jpg","url":"https:\/\/wiki.edu.vn\/wiki4\/wp-content\/uploads\/2023\/08\/download.jpg","width":100,"height":100},"url":"https:\/\/wiki.edu.vn\/en\/wiki24\/armstrong-siddeley-sapphire-wikipedia\/","about":["Wiki"],"wordCount":3112,"articleBody":"1940s British turbojet aircraft engineThe Armstrong Siddeley Sapphire is a British turbojet engine that was produced by Armstrong Siddeley in the 1950s. It was the ultimate development of work that had started as the Metrovick F.2 in 1940, evolving into an advanced axial flow design with an annular combustion chamber that developed over 11,000\u00a0lbf (49\u00a0kN). It powered early versions of the Hawker Hunter and Handley Page Victor, and every Gloster Javelin. Production was also started under licence in the United States by Wright Aeronautical as the J65, powering a number of US designs. The Sapphire’s primary competitor was the Rolls-Royce Avon.Design and development[edit]Design evolution of the Sapphire started at Metropolitan-Vickers (Metrovick) in 1943 as an offshoot of the F.2 project. With the F.2 reaching flight quality at about 1,600\u00a0lbf (7,100\u00a0N), Metrovick turned to producing larger designs, both an enlarged F.2 known as the Beryl, as well as the much larger F.9 Sapphire. (The names were chosen after a decision to use gemstones for future engine names). The Beryl eventually developed 4,000\u00a0lbf (18\u00a0kN) thrust, but the only project to select it, the Saunders-Roe SR.A\/1, was cancelled. The Ministry of Supply (MoS) designated the F.9 as the MVSa.1.In 1948[1] Metrovick exited the jet engine industry.[2][3] Armstrong Siddeley, who already had a turbine development of their own, the ASX, took over the MVSa.1, now renamed ASSa.1.After a redesign it emerged as the ASSa.2. In December 1949 the ASSa.2 completed an acceptance test at 7,380\u00a0lbf (32,800\u00a0N). Its competitor, the Avon Ra.3 had a design thrust of 6,500\u00a0lbf (29,000\u00a0N) at that time.[4] A number of companies expressed interest in the Sapphire, and it was considered as either the main or backup powerplant for most British designs of the late ’40s and early ’50s.The ASSa.5 with 7,500\u00a0lbf (33,000\u00a0N) thrust was used only on the English Electric P.1A, prototype for the Lightning. A simple fixed-nozzle reheat was fitted to extend the performance boundary for stability and control testing from about Mach 1.1 to beyond Mach 1.5.[5] Future versions of the Lightning were powered by the Avon.The ASSa.6, 8,300\u00a0lbf (37,000\u00a0N), was used on the Gloster Javelin FAW Mk.1, Hawker Hunter F.Mk.2 and F.Mk.5, and the prototype Sud Ouest SO 4050 Vautour. The higher thrust ASSa.7 at 11,000\u00a0lbf (49\u00a0kN) was the first British engine to be rated above 10,000\u00a0lbf (44\u00a0kN) and it powered the Gloster Javelin FAW Mk.7, Handley Page Victor B.Mk.1 and a prototype Swiss fighter-bomber, the FFA P-16.The Sapphire compressor operated well, free from surging,[6] over its complete RPM range without the need for variable inlet guide vanes (VIGV) or bleed. However, early compressor stages suffered from fatigue due to rotating stall at low RPM and various fixes, such as lacing wire, were incorporated. Curtiss-Wright introduced variable ramps on the Wright J65 at the entry to the compressor[7] to prevent the stalling and blade excitation. Armstrong-Siddeley tested a similar solution on the Sapphire but incorporated blade changes instead to reduce the blade response to the stalling.[8]Caygill[9] states that one of the most serious problems encountered throughout the life of the Gloster Javelin was caused by “centre-line closure” on the Sapphire engine. Flying through thick cloud could cause the compressor case to shrink and rub the blades causing catastrophic engine failures and loss of the aircraft. “Centre-line closure” also caused a Sapphire failure on a Victor B.1.[10]An afterburner with limited boost was required for the Javelin’s ASSa.7, making it the ASSa.7LR. 12% boost was required at high altitudes to regain the bomber intercept performance that had been lost carrying the new de Havilland Firestreak missiles.[9] Afterburners with a low boost requirement were sometimes known as “wee-heat”.[9] Other low-boost reheats have included the “tailpipe augmentation”(TPA) on the F-86H (J73) with +10% at take-off[11] and “Bristol Simplified Reheat”(BSR), with about 16% boost at take-off, tested on Derwent V, Orenda, Olympus[12] and Orpheus engines.[13]Variants[edit]MVSa.1Ministry of Supply designation of the original Metropolitan-Vickers F.9 Sapphire, derived from the Metropolitan-Vickers F.2\/4 Beryl. Design work on this much larger engine started in 1943.ASSa.3Completed a 150-hour Service Type Test in November 1951 at a sea level rating of 7,500\u00a0lbf (33.36\u00a0kN) at an s.f.c. of 0.91ASSa.4[14]ASSa.5Early Armstrong Siddeley developed Sapphire engines.[14]ASSa.5RReheated engines fitted to the English Electric P.1A.ASSa.6Later engines developed for the Gloster Javelin FAW Mk.1, Hawker Hunter F.Mk.2, F.Mk.5 and the prototype Sud Ouest SO 4050 VautourASSa.7Rated at 11,000\u00a0lbf (49\u00a0kN), powering the Gloster Javelin FAW Mk.7, Handley Page Victor B.Mk.1 and the prototype FFA P-16.ASSa.7LREngines with a 12% augmentation reheat system for use above 20,000\u00a0ft (6,100\u00a0m), powering the Gloster Javelin FAW Mk.8.Wright J65Licence production in the United States by Wright AeronauticalASSa.8ASSa.9[14]ASSa.12Sapphire 101(ASSa.6)Sapphire 104(ASSa.12)Sapphire 202(ASSa.7)Engines on display[edit]An Armstrong Siddeley Sapphire is on static display at the Midland Air Museum, Coventry Airport, Warwickshire.Very few Armstrong Siddeley Sapphire engines exist, other known examples are preserved at the Jet Age Museum in Gloucester, England, and the Malta Aviation Museum at Ta’ Qali.Specifications (ASSa.7)[edit]Data from Jane’s.[15]General characteristicsType: TurbojetLength: 125.2\u00a0in (3,180\u00a0mm)Diameter: 37.55\u00a0in (954\u00a0mm)Dry weight: 3,050\u00a0lb (1,383\u00a0kg)ComponentsCompressor: 13-stage axial flowCombustors: Annular with 24 hockey-stick vaporisersTurbine: Two-stageFuel type: Aviation keroseneOil system: Flood feed, minimum oil pressure 12\u00a0psi (83\u00a0kPa), tank capacity 18\u00a0imp\u00a0pt (10\u00a0L)PerformanceSee also[edit]Related developmentComparable enginesRelated listsReferences[edit]Notes[edit]^ “armstrong siddeley | gloster javelin | 1956 | 0017 | Flight Archive”. www.flightglobal.com. Archived from the original on 19 November 2011. ^ Depending on the sources, Metrovick either left the engine business on their own to concentrate on steam turbines, or were forced from the market by the Ministry of Supply in order to reduce the number of companies they had to deal with.^ Gunston 1989, p.102. Note: “…the firm had decided in 1947, under Ministry pressure, to get out of aviation”^ “electric company | english electric | 1955 | 1780 | Flight Archive”. www.flightglobal.com. Archived from the original on 25 April 2016. ^ “Testing Years” Roland Beamont, Ian Allan Ltd. Londondon, ISBN\u00a00 7110 1072 2, p.93^ “armstrong siddeley | 1956 | 0018 | Flight Archive”. Archived from the original on 22 May 2013.^ “armstrong siddeley | 1956 | 0022 | Flight Archive”. Archived from the original on 24 April 2015.^ “1956 | 1599 | Flight Archive”. Archived from the original on 26 April 2016.^ a b c Javelin From The Cockpit, Peter Caygill, Pen & Sword Books Ltd., ISBN\u00a0978-1-84884-656-2^ The Handley Page Victor Volume 1, Roger R Brooks, Pen & Sword Aviation 2007, ISBN\u00a0978 1 84415 411 1, p.195^ “seven decades of progress” General Electric, Aero Publishers Inc. 1979, Fallbrook, ISBN\u00a00-8168-8355-6, p. 83^ “Olympus-the first forty years” Alan Baxter, Rolls-Royce Heritage Trust, 1990, ISBN\u00a09780951171097, p.26^ “1959 | 2122 | Flight Archive”. Archived from the original on 19 November 2011.^ a b c Taylor, John W.R. FRHistS. ARAeS (1955). Jane’s All the World’s Aircraft 1955-56. London: Sampson, Low, Marston & Co Ltd.^ Taylor, John W.R. FRHistS. ARAeS (1962). Jane’s All the World’s Aircraft 1962-63. London: Sampson, Low, Marston & Co Ltd.Bibliography[edit]Gunston, Bill. World Encyclopedia of Aero Engines. Cambridge, England. Patrick Stephens Limited, 1989. ISBN\u00a01-85260-163-9Kay, Anthony L. (2007). Turbojet History and Development 1930-1960. Vol.\u00a01 (1st\u00a0ed.). Ramsbury: The Crowood Press. ISBN\u00a0978-1-86126-912-6.External links[edit]"},{"@context":"http:\/\/schema.org\/","@type":"BreadcrumbList","itemListElement":[{"@type":"ListItem","position":1,"item":{"@id":"https:\/\/wiki.edu.vn\/en\/wiki24\/#breadcrumbitem","name":"Enzyklop\u00e4die"}},{"@type":"ListItem","position":2,"item":{"@id":"https:\/\/wiki.edu.vn\/en\/wiki24\/armstrong-siddeley-sapphire-wikipedia\/#breadcrumbitem","name":"Armstrong Siddeley Sapphire – Wikipedia"}}]}]