| Silvercrest | |
|---|---|
 | |
| The engine on display at Paris Air Show 2013 | |
| Type | Turbofan |
| National origin | France |
| Manufacturer | Safran |
| First run | September 2012 [1] |
| Major applications | Cessna Citation Hemisphere |
| Number built | 7 (as of Summer 2014) [2] |
The Safran Silvercrest is a French turbofan under development by Safran Aircraft Engines.
The engine was announced at the 2006 National Business Aviation Association convention. [3] Certification was originally slated for the end of 2010 or early 2011. [4] In early 2008 the high pressure spool and combustor have been run in a US$120 million core-demonstrator called SM-X, reaching the take-off speed of 20,300rpm. [5]
The First Engine To Test started ground testing in September 2012. [1] [6] In May 2013, in-flight tests were targeted for the fourth quarter of the year. [7] They finally started in July 2014 on a Grumman Gulfstream II and should take place in Istres-Le Tubé Air Base. [8] In 2015, engine certification was rescheduled for late 2016. [9] In 2015, Safran passed €654 million of depreciation for amortization for the Silvercrest program. [10]
In November 2016, issues were traced to airflow through the engine not as controlled as expected, a side-effect of the axial-centrifugal high-pressure compressor selection, controlling software was adapted to maintain a steady airflow and active clearance controls were added to the low pressure turbine ; in May 2017, altitude tests should begin soon in Russia for an early 2018 certification. [11] The 11,450 lbf (50.9 kN) Silvercrest 2D was to power the Dassault Falcon 5X and the 12,000 lbf (53 kN) 2C the Cessna Citation Hemisphere, EASA certification was expected in spring 2018 and FAA certification in August 2018. [12]
In October 2017, after Safran discovered high-pressure compressor response problems at high altitudes and low airspeeds on its flying testbed in San Antonio, Dassault announced the Falcon 5X introduction could be further delayed after 50 test flight hours, and do not rule out switching its engine supplier. An axial-centrifugal high-pressure compressor is common below 5,000 lbf (22 kN) but rare for the 10,000–12,000 lbf (44–53 kN) range. Textron Aviation declared that they were confident that these problems will be solved when it powers the Citation Hemisphere. [13] Until 2015, issues were mostly oil-fuel heat exchanger problems, carcass distortion and clearance control challenges of the high-pressure section. [14]
Optimizing the settings, the control laws and positioning of the variable stator vanes will recover a part of the losses, but not all. Flowpath will not be too modified and no stages or vanes will be added, the fixes selection will establish the length of the delay and the schedule will be revised before 2017 ends to recover all the surge margin and to operate as planned across the flight envelope. The problem is due to the axial part, not the centrifugal, and is not related to the overall compressor architecture. [15] At this time the test engines had logged 800 flights, and the one concerned had 90 hours, including 30 hours on the ground and 60 hours in the air. [16]
On 13 December 2017, Dassault abandoned the Silvercrest due to technical and schedule risks, ended the 5X development and launched a new Falcon with the same cross section, Pratt & Whitney Canada engines and a 5,500 nmi (10,200 km) range for a 2022 introduction. Compliant Silvercrest engines were originally planned for the end of 2013 but technical issues led Safran to postpone them to the end of 2017, leading to delay the 5X introduction from 2017 to 2020, and the high pressure compressor issues in the fall of 2017 delayed it further with performance shortfalls, preventing a 2020 service entry. [17]
In December 2017, Textron Aviation declared that the Silvercrest delays did not impact the Hemisphere programme with a first flight still planned in 2019 and an introduction after 2020 and Textron confirmed its selection for the Hemisphere after Dassault cancelled the 5X. [18] However, in April 2018, they declared that they suspended the Hemisphere Program because of the ongoing problems with the Silvercrest engine. [19]
In May 2018, Safran announced it had launched a high-pressure compressor redesign for a go-ahead decision by the middle of 2019, after testing, shelving the Hemisphere program if problems cannot be fixed. [20] The redesigned compressor will be tested in July 2019 to prove the engine operation. [21] By October 2018, Safran had amassed over 9,000 test hours and 300 in flight. [22] Safran needs a second customer to justify its investment, but is still optimistic for the engine's future. [23]
In July 2019, Textron suspended the Cessna Citation Hemisphere development as its turbofans did not meet objectives: the new high pressure compressor exceeded expectations during ground tests but further trials were necessary to "confirm engine improvements and complete overall engine performance and durability validation" and Safran would continue the effort as an "R&T platform". [24] For Safran, insufficient skills retention was causing the repetition of technical issues as design engineers retire. [25]
It was originally designed as an 8,500–10,500 lbf (38–47 kN) thrust turbofan. [26] It should power super mid-size to large cabin business jets or 40 to 60-seat regional jets with a Maximum Takeoff Weight of 45,000 to 60,000 lb (20,000 to 27,000 kg). [27] In 2016 the thrust range was quoted as 10,000–12,000 lbf (44–53 kN). [28]
The two-shaft engine architecture includes a 42.5 in (108 cm) fan with solid wide-chord swept blades, followed by 4 booster stages, all driven by a 4-stage low pressure turbine. The high pressure spool has 4 axial compressor stages and 1 centrifugal stage, driven by a single-stage turbine. [1] An axi-centrifugal compressor is unusual for an engine in this thrust range. [28] Turbomeca, which like Snecma is a part of the SAFRAN Group, participates in the design of the centrifugal compressor stage. [4]
Design in 2007 featured a smaller 40-inch fan, no booster, one more high-pressure compressor stage, one low-pressure turbine stage less and a lower 4.5 bypass ratio, a 27:1 overall pressure ratio and a core pressure ratio of "over 17". [4] [29]
Data fromSnecma. [33]
Comparable engines
Related lists
A business jet, private jet, or bizjet is a jet aircraft designed for transporting small groups of people, typically business executives and high-ranking associates. Business jets are generally designed for faster air travel and more personal comfort than commercial aircraft, and may be adapted for other roles, such as casualty evacuation or express parcel deliveries, and some are used by public bodies, government officials, VIPs, or even the military.
The Rolls-Royce BR700 is a family of turbofan engines for regional jets and corporate jets. It is manufactured in Dahlewitz, Germany, by Rolls-Royce Deutschland: this was initially a joint venture of BMW and Rolls-Royce plc established in 1990 to develop this engine. The BR710 first ran in 1995. The United States military designation for the BR725 variant is F130.
The PowerJet SaM146 is a turbofan engine produced by the PowerJet joint venture between Snecma (Safran) of France and NPO Saturn of Russia. Developing 68–80 kN (15,000–18,000 lbf) of thrust, the SaM146 is used on the Sukhoi Superjet 100.
The Snecma M88 is a French afterburning turbofan engine developed by Snecma for the Dassault Rafale fighter.
The SNECMA M53 is an afterburning turbofan engine developed for the Dassault Mirage 2000 fighter by Snecma. The engine is in service with different air forces, including the latest Mirage 2000-5 and 2000-9 multirole fighters.
The Williams FJ44 is a family of small, two-spool, turbofan engines produced by Williams International for the light business jet market. Until the recent boom in the very light jet market, the FJ44 was one of the smallest turbofans available for civilian applications. Although basically a Williams design, Rolls-Royce was brought into the project at an early stage to design, develop, and manufacture an air-cooled high-pressure (HP) turbine for the engine. The FJ44 first flew on July 12, 1988 on the Scaled Composites/Beechcraft Triumph aircraft.
The Pratt & Whitney Canada PW300 series is a family of turbofan jet engines developed by Pratt & Whitney Canada specifically for business jet applications.
The Garrett TFE731 is a family of geared turbofan engines commonly used on business jet aircraft. Garrett AiResearch originally designed and built the engine, which due to mergers was later produced by AlliedSignal and now Honeywell Aerospace.
The CFE CFE738 is a small turbofan engine aimed at the business/commuter jet market manufactured by the CFE Company, and is used on the Dassault Falcon 2000.
The Lycoming ALF 502/LF 507 is a geared turbofan engine produced by Lycoming Engines, AlliedSignal, and then Honeywell Aerospace. The U.S. military designation for the ALF 502 is YF102.
The Rolls-Royce RB282 is a new series of twin-spool turbofan engines under development by Rolls-Royce.
The Rolls-Royce/Snecma Olympus 593 was an Anglo-French turbojet with reheat, which powered the supersonic airliner Concorde. It was initially a joint project between Bristol Siddeley Engines Limited (BSEL) and Snecma, derived from the Bristol Siddeley Olympus 22R engine. Rolls-Royce Limited acquired BSEL in 1966 during development of the engine, making BSEL the Bristol Engine Division of Rolls-Royce.
The Honeywell HTF7000 is a turbofan engine produced by Honeywell Aerospace. Rated in the 6,540–7,624 lbf (29.09–33.91 kN) range, the HTF7000 is used on the Bombardier Challenger 300/350, Gulfstream G280, Embraer Legacy 500/450 and the Cessna Citation Longitude. Its architecture could be extended for a range of 8,000 to 10,000 lbf thrust.
The Pratt & Whitney Canada PW800 is a series of turbofan engines in the 10,000–20,000 lbf (44–89 kN) thrust class, manufactured by Pratt & Whitney Canada. Intended for the regional jet and business jet market, the gear-less PW800 shares a common core with the larger, geared PW1000G. The first variants were certified on February 15, 2015, to power the new Gulfstream G500/G600. After that it has been certified also for the Dassault Falcon 6X in 2021.
The General Electric Passport is a turbofan developed by GE Aerospace for large business jets. It was selected in 2010 to power the Bombardier Global 7500 and 8000, first run on June 24, 2013, and first flown in 2015. It was certified in April 2016 and powered the Global 7500 first flight on November 4, 2016, before its 2018 introduction. It produces 14,000 to 20,000 lbf of thrust, a range previously covered by the General Electric CF34. A smaller scaled CFM LEAP, it is a twin-spool axial engine with a 5.6:1 bypass ratio and a 45:1 overall pressure ratio and is noted for its large one-piece 52 in (130 cm) fan 18-blade titanium blisk.
The Cessna Citation Longitude is a business jet produced by Cessna, part of the Cessna Citation family. It remains the largest business jet by Cessna. Announced at the May 2012 EBACE, the Model 700 made its first flight on October 8, 2016, with certification obtained in September 2019. The aluminum airframe has the fuselage cross-section of the Citation Latitude, stretched by a seat row. Powered by Honeywell HTF7000 turbofans, it has a new ~28° swept wing and a T-tail for a 3,500 nmi (6,500 km) range.
The General Electric GE9X is a high-bypass turbofan developed by GE Aerospace exclusively for the Boeing 777X. It first ran on the ground in April 2016 and first flew on March 13, 2018; it powered the 777-9's maiden flight in early 2020. It received its Federal Aviation Administration (FAA) type certificate on September 25, 2020. Derived from the General Electric GE90 with a larger fan, advanced materials like ceramic matrix composites (CMCs), and higher bypass and compression ratios, it was designed to improve fuel efficiency by 10% compared to the GE90. It is rated at 110,000 lbf (490 kN) of thrust, which is 5,000 lbf less than the GE90 highest thrust variant, the GE90-115, rated at 115,000 lbf (510 kN).
The General Electric Catalyst is a turboprop engine by GE Aviation. It was announced on 16 November 2015 and will power the Beechcraft Denali, it first ran on December 22, 2017, and should be certified in 2024. The 850 to 1,600 hp engine aims for 20% better efficiency than its competition thanks to a 16:1 overall pressure ratio, variable stator vanes, cooled turbine blades, 3D printed parts and FADEC.
The Cessna Citation Hemisphere was a business jet project by Cessna. Announced in November 2015, it was then expected to fly in 2019 but its development was suspended in April 2018 due to a delay in the development of its Safran Silvercrest engines. It was designed for Mach 0.9 and would have a 4,500 nautical miles (8,300 km) range.
The Dassault Falcon 6X is a large, long-range business jet developed by Dassault Aviation in France. Its precursor, the Falcon 5X twinjet, was launched in 2013, rolled-out in 2015 and made its first flight on July 5, 2017, but its development was frozen as its Safran Silvercrest engine failed to meet performance objectives. In December 2017, the Falcon 6X was launched as a stretched version with PW812D turbofans, made its first flight on 10 March 2021, and entered service on 30 November 2023.
