View source for Safran Silvercrest

{{short description|French turbofan aircraft engine}}
<!-- This article is a part of [[Wikipedia:WikiProject Aircraft]]. Please see [[Wikipedia:WikiProject Aircraft/page content]] for recommended layout. -->
{|{{Infobox Aircraft Begin
 |name= Silvercrest 
 |image= File:Safran Silvercrest.png
 |caption= The engine on display at [[Paris Air Show]] 2013
}}
{{Infobox Aircraft Engine
 |type= [[Turbofan]]
 |national origin = [[France]]
 |manufacturer= [[Safran]] 
 |first run= September 2012<ref name=AIN31Oct2013>{{cite news |url= http://www.ainonline.com/aviation-news/nbaa-convention-news/2012-10-30/snecma-puts-silvercrest-engine-test |title= Snecma puts Silvercrest engine to test |publisher= Aviation International News |author= Thierry Dubois |date= 31 Oct 2013 |access-date= 2013-07-22 |archive-date= 2014-10-20 |archive-url= https://web.archive.org/web/20141020031443/http://www.ainonline.com/aviation-news/nbaa-convention-news/2012-10-30/snecma-puts-silvercrest-engine-test |url-status= dead }}</ref>
 |major applications= [[Cessna Citation Hemisphere]]
 |number built = 7 (as of Summer 2014)<ref>{{cite news |url= http://www.exvipaviationint.com/engines-special-report-snecma |title= Engines special report: Snecma |work= Executive & VIP Aviation International |date= Summer 2014}}</ref> 
 |program cost = {{USD}} 500–600 million (2008 information)<ref name="600 M dollars">{{cite news |url= http://www.usinenouvelle.com/article/snecma-va-investir-600-millions-de-dollars-dans-le-silvercrest.N22731 |title= Snecma va investir 600 millions de dollars dans le Silvercrest |work= L'usine nouvelle |date= 30 Jan 2008 |language= fr}}</ref>
 |unit cost = 
 |developed from = 
 |developed into = 
 |variants with their own articles = 
}}
|}

The '''Safran Silvercrest''' is a French [[turbofan]]  under development by [[Safran Aircraft Engines]].

==Development==

The engine was announced at the 2006 [[National Business Aviation Association]] convention.<ref>{{cite news |url= http://www.asdnews.com/news-9861/SILVERCREST:_a_new_name_in_propulsion_for_business_aviation.htm |title= SILVERCREST: a new name in propulsion for business aviation |publisher=[[SAFRAN]] |date= 17 Oct 2006 }}</ref>
Certification was originally slated for the end of 2010 or early 2011.<ref name=AIN5May2007>{{cite news |url= http://www.ainonline.com/aviation-news/ebace-convention-news/2007-05-04/snecma-silvercrest-core-engine-set-first-run |title= Snecma Silvercrest core engine set for first run |work= Aviation International News |author= Thierry Dubois |date= 5 May 2007}}</ref>
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 20,300&nbsp;rpm.<ref>{{cite news |url= http://www.ainonline.com/aviation-news/ebace-convention-news/2008-05-19/snecma-silvercrest-engine-completes-core-tests |title= Snecma Silvercrest engine completes core tests |work= Aviation International News |author= Thierry Dubois |date=20 May 2008}}</ref>

[[File:Dassault Falcon 5X model 2015.png|thumb|[[Falcon 5X]] Model at the 2015 Paris Air Show]]

The First Engine To Test started ground testing in September 2012.<ref name=AIN31Oct2013/><ref>{{cite web |url= http://www.ainonline.com/aviation-news/ebace-convention-news/2013-05-20/snecma-close-second-application-silvercrest |author= Ian Goold |title= Snecma Close To Second Application For Silvercrest |work= Aviation International News |date= 20 May 2013}}</ref>
In May 2013, in-flight tests were targeted for the fourth quarter of the year.<ref>{{cite news |title= Snecma eyes maiden Silvercrest sortie in fourth quarter |url= http://www.flightglobal.com/news/articles/ebace-snecma-eyes-maiden-silvercrest-sortie-in-fourth-quarter-386188/ |work= Flightglobal |author= Dominic Perry |date= 23 May 2013}}</ref>
They finally started in July 2014 on a [[Grumman Gulfstream II]] and should take place in [[Istres-Le Tubé Air Base]].<ref>{{cite news |url= http://www.ainonline.com/aviation-news/ainalerts/2014-07-15/snecma-begins-flight-testing-silvercrest-modified-gulfstream-ii |title=Snecma Begins Flight-testing Silvercrest on Modified Gulfstream II |work= Aviation International News |author=Thierry Dubois |date= 15 Jul 2014}}</ref>
In 2015, engine certification was rescheduled for late 2016.<ref>{{cite news |url= http://www.ainonline.com/aviation-news/business-aviation/2015-03-12/snecma-silvercrest-schedule-slips-2016 |title=Snecma Silvercrest Schedule Slips into 2016  |work= Aviation International News |date= 12 Mar 2015}}</ref>
In 2015, Safran passed €654 million of [[depreciation]] for [[Amortization (accounting)|amortization]] for the Silvercrest program.<ref>{{cite news |url=https://www.ainonline.com/aviation-news/business-aviation/2018-02-28/safran-mum-silvercrest-ramping-cfm-leaps|title=Snecma Mum on Silvercrest, Ramping Up on CFM Leaps |author= Guillaume Lecompte-Boinet |date= February 28, 2018 |work= AIN}}</ref>

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.<ref>{{cite news |url= https://www.flightglobal.com/news/articles/ebace-rivals-for-power-in-the-business-aviation-eng-437181/ |title= Rivals for power in the business aviation engine market |date= 19 May 2017 |work= Flight Global |author= Murdo Morrison }}</ref>
The {{cvt|11,450|lbf|kN}} Silvercrest 2D was to power the [[Dassault Falcon 5X]] and the {{cvt|12,000|lbf|kN}} 2C the [[Cessna Citation Hemisphere]], [[EASA]] certification was expected in spring 2018 and [[FAA]] certification in August 2018.<ref>{{cite news |url= http://www.ainonline.com/aviation-news/business-aviation/2017-06-26/safran-silvercrest-have-two-takeoff-thrust-ratings |title= Safran Silvercrest To Have Two Takeoff Thrust Ratings |author= Chad Trautvetter |date= June 26, 2017 |work= Aviation International News}}</ref>

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.<!--<ref name=Flight9oct2017/>-->
An axial-centrifugal high-pressure compressor is common below {{cvt|5,000|lbf|kN}} but rare for the {{cvt|10,000|-|12,000|lbf|kN}} range.<!--<ref name=Flight9oct2017/>-->
[[Textron Aviation]] declared that they were confident that these problems will be solved when it powers the Citation Hemisphere.<ref name=Flight9oct2017>{{cite news |url= https://www.flightglobal.com/news/articles/nbaa-dassault-discloses-new-delay-for-falcon-5x-441977/ |title= Dassault discloses new delay for Falcon 5X |date= 9 Oct 2017 |author= Stephen Trimble |work= Flightglobal}}</ref>
Until 2015, issues were mostly oil-fuel [[heat exchanger]] problems, [[structural frame|carcass]] distortion and [[Tip clearance|clearance]] control challenges of the high-pressure section.<ref>{{cite news |url= http://aviationweek.com/nbaa-2017/safran-engine-issues-cause-further-dassault-falcon-5x-delay |title= Safran Engine Issues Cause Further Dassault Falcon 5X Delay |date= Oct 10, 2017 |author= Guy Norris |work= Aviation Week Network}}</ref>

Optimizing the settings, the control laws and positioning of the variable stator vanes will recover a part of the losses, but not all.<!--<ref name=AvWeek11oct2017/>-->
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.<!--<ref name=AvWeek11oct2017/>-->
The problem is due to the axial part, not the centrifugal, and is not related to the overall compressor architecture.<ref name=AvWeek11oct2017>{{cite news |url= http://aviationweek.com/nbaa-2017/safran-mulls-silvercrest-fix-options |title= Safran Mulls Silvercrest Fix Options |date= Oct 11, 2017 |author= Guy Norris |work= Aviation Week Network}}</ref>
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.<ref>{{cite news |url= https://www.ainonline.com/aviation-news/business-aviation/2017-10-11/safran-planning-fix-silvercrest-compressor-issue |title= Safran Planning Fix for Silvercrest Compressor Issue |author= Matt Thurber |date= October 11, 2017 |work= AIN}}</ref>

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 {{cvt|5,500|nmi|km}} range for a 2022 introduction.<!--<ref name=Dassault13dec2017/>-->
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.<ref name=Dassault13dec2017>{{cite press release |url= https://www.dassaultfalcon.com/en/MediaCenter/Newsd/Pages/PR%202017/Falcon-5X.aspx/ |title= Dassault confirms termination for 5X |publisher= Dassault |date= 13 December 2017 |access-date= 14 December 2017 |archive-date= 14 December 2017 |archive-url= https://web.archive.org/web/20171214014545/https://www.dassaultfalcon.com/en/MediaCenter/Newsd/Pages/PR%202017/Falcon-5X.aspx/ |url-status= dead }}</ref>

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.<ref>{{cite news |url= https://www.flightglobal.com/news/articles/textron-aviation-still-committed-to-silvercrest-engi-444158/ |title= Textron Aviation still committed to Silvercrest engine for Hemisphere |date= 13 Dec 2017 |author= Stephen Trimble |work= Flightglobal}}</ref> However, in April 2018, they declared that they suspended the Hemisphere Program because of the ongoing problems with the Silvercrest engine.<ref name="suspendedTextron">{{cite news |url= https://www.ainonline.com/aviation-news/business-aviation/2018-04-18/textron-aviation-suspends-citation-hemisphere-program |title=Textron Aviation Suspends Citation Hemisphere Program |date= 2018-04-18 |publisher=[[Aviation International News]]|accessdate=2018-05-04}}</ref>

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.<ref>{{cite news |url= https://www.flightglobal.com/news/articles/ebace-silvercrest-compressor-redesign-underway-as-h-448945/ |title= Silvercrest compressor redesign underway as Hemisphere awaits decision |date= 28 May 2018 |author= Stephen Trimble |work= Flightglobal}}</ref>
The redesigned compressor will be tested in July 2019 to prove the engine operation.<ref>{{cite news |url= https://www.ainonline.com/aviation-news/business-aviation/2018-09-20/hemisphere-still-part-textron-aviations-future |title= Hemisphere Still Part of Textron Aviation's Future |author= Matt Thurber |date= September 20, 2018 |work= AIN}}</ref>
By October 2018, Safran had amassed over 9,000 test hours and 300 in flight.<ref>{{cite news |url= https://www.ainonline.com/aviation-news/business-aviation/2018-10-17/safran-silvercrest-fix-test-mid-2019 |title= Safran: Silvercrest Fix To Test in Mid-2019 |author= Mark Huber - |date= October 17, 2018 |work= [[Aviation International News]]}}</ref>
Safran needs a second customer to justify its investment, but is still optimistic for the engine's future.<ref>{{cite news |url= https://www.flightglobal.com/news/articles/safran-still-needs-additional-silvercrest-customers-452978/ |title= Safran still needs additional Silvercrest customers |date= 25 Oct 2018 |work= Flightglobal |author= Dominic Perry}}</ref>

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&D|R&T]] platform".<ref>{{cite news |url= https://www.flightglobal.com/news/articles/textron-suspends-cessna-hemisphere-programme-459720/ |title= Textron suspends Cessna Hemisphere programme |date= 17 July 2019 |author= Michael Gubisch |work= Flightglobal}}</ref>
For Safran, insufficient skills retention was causing the repetition of technical issues as design engineers retire.<ref>{{cite news |url= https://aviationweek.com/business-aviation/safran-back-square-one-business-aviation |title= Safran Back To Square One In Business Aviation |date= Jul 25, 2019 |author= Guy Norris and Thierry Dubois |work= Aviation Week & Space Technology}}</ref>

== Design ==
[[File:Safran Silvercrest, EBACE 2018, Le Grand-Saconnex (BL7C0444) (cropped).jpg|thumb|presented at [[EBACE]] 2018]]

It was originally designed as an {{cvt|8,500|-|10,500|lbf|kN}} thrust turbofan.<ref name=AIN30nov2006>{{cite news |title= Snecma develops new bizav engine |url= http://ainonline.com/aviation-news/singapore-air-show/2006-11-30/snecma-develops-new-bizav-engine |work= Aviation International News |author= Jeff Apter |date= 30 Nov 2006}}</ref>
It should power super mid-size to large cabin [[business jet]]s or 40 to 60-seat regional jets with a [[Maximum Takeoff Weight]] of {{cvt|45,000|to|60,000|lb|kg}}.<ref>{{cite news |url= http://www.asdnews.com/news-12295/Snecma_Announces_Silvercrest_Core_Demonstrator_First_Parts_Delivered_.htm |title= Snecma Announces Silvercrest Core demonstrator First Parts Delivered |publisher= [[SAFRAN]] |date= 22 May 2007}}</ref>
In 2016 the thrust range was quoted as {{cvt|10,000|-|12,000|lbf|kN}}.<ref name=AW2016nov>{{cite news |url= http://aviationweek.com/nbaa-2016/safran-reveals-revised-silvercrest-test-plan |title= Safran Reveals Revised Silvercrest Test Plan |date= November 1, 2016 |work= Aviation Week}}</ref>

The two-shaft engine architecture includes a {{cvt|42.5|in|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 compressor|centrifugal]] stage, driven by a single-stage turbine.<ref name=AIN31Oct2013/>
An axi-centrifugal compressor is unusual for an engine in this thrust range.<ref name=AW2016nov/>
[[Turbomeca]], which like Snecma is a part of the [[SAFRAN]] Group, participates in the design of the centrifugal compressor stage.<ref name=AIN5May2007/>

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".<ref name=AIN5May2007/><ref>{{cite news |url= http://www.ainonline.com/aviation-news/aviation-international-news/2007-04-30/snecma-silvercrest-core-run-later-year |title= Snecma Silvercrest core to run later this year |work= Aviation International News |author= Thierry Dubois |date=30 Apr 2007}}</ref>

==Applications==
;Silvercrest 2C
: [[Cessna Citation Hemisphere]], first flight 2019, with over {{cvt|12,000|lbf|kN}} of thrust.<ref>{{cite press release |url= http://txtav.com/en/newsroom/2016/10/cessna-selects-engine |title= Cessna selects engine, avionics and fly-by-wire suppliers for the latest in its large-cabin Citation business jet family |date= October 31, 2016 |publisher= Textron Aviation}}</ref> Textron announced the suspension of the program in April 2018.<ref name="suspendedTextron"/>

;Silvercrest SC-2D
: [[Dassault Falcon 5X]] ; {{cvt|11450|lbf|kN}}, both aircraft and official engine selection were simultaneously unveiled at the [[National Business Aviation Association]] annual convention on October 21, 2013, entry into service was delayed to 2020.<ref name="FlightGlobal">{{cite web|url=https://www.flightglobal.com/news/articles/dassault-confirms-two-year-delay-for-5x-421138/|title=Dassault confirms two-year delay for 5X|publisher=flightglobal.com |date=2016-01-29 |accessdate=2016-01-29}}</ref>  Dassault announced the cancellation of the 5X program on 13 December 2017.<ref name=Dassault13dec2017/> On 6 September 2018, [[Dassault Aviation]] and Safran ended with [[US$]]280 million in [[compensatory damages]] paid by Safran.<ref>{{cite press release |url= https://www.dassault-aviation.com/en/group/press/press-kits/signature-amicable-settlement-safran/ |title= Signature of an amicable settlement with Safran |date= 2018-09-06 |publisher= Dassault Aviation}}</ref>

==Specifications (2D)==
[[File:Snecma Silvercrest business jet engine PAS 2013 02.jpg|thumb|Side view]]
{{jetspecs
|<!-- If you do not understand how to use this template, please ask at [[Wikipedia talk:WikiProject Aircraft]] -->
<!-- Please include units where appropriate (main comes first, alt in parentheses). If data are missing, leave the parameter blank (do not delete it). For additional lines, end your alt units with )</li> and start a new, fully-formatted line with <li> -->
|ref=''Snecma.''<ref>{{cite web |url= http://www.safran-aircraft-engines.com/commercial-engines/business-jet/silvercrestr2d |title= Silvercrest 2D for the Dassault Aviation Falcon 5X |publisher= Safran Aircraft Engines}}</ref>
|type=axial and centrifugal flow, twin-shaft, bypass [[turbofan]] engine
|length=approx. {{convert|74|in|cm}}<ref name=AIN5May2007/>
|diameter= {{convert|42.5|in|cm}} Fan
|weight={{convert|{{#expr:11450/5round0}}|lb|kg|abbr=on}}<ref name=AIN20131022/>
|compressor= 4 low-pressure stages, 4 high-pressure blisks + 1 centrifugal stage
|combustion=
|turbine= 1 high-pressure, 4 low-pressure stages 
|fueltype=
|oilsystem=
|power=
|thrust={{convert|11,450|lbf|kN|abbr=on}}
|compression= 38.5 <ref>{{cite web |url= https://fenix.tecnico.ulisboa.pt/downloadFile/844820067124119/Thesis_JoaoFerro.pdf |title= New Aircraft Concepts for Improved Environmental and Energetic Efficiency |publisher= Técnico Lisboa |date= November 2014}}</ref>
|bypass=5.9:1
|aircon=
|turbinetemp=
|fuelcon=
|specfuelcon=
|power/weight=
|thrust/weight=5<ref name=AIN20131022>{{cite news |url= http://www.ainonline.com/aviation-news/business-aviation/2013-10-22/snecmas-silvercrest-power-new-falcon-jet |title= Snecma's Silvercrest To Power New Falcon Jet |date= October 22, 2013 |work= Aviation International News}}</ref>
}}

==See also==
{{aircontent
<!-- first, the related articles that do not fit the specific entries: -->
|see also=
<!-- designs which were developed into or from this aircraft or engine: -->
|related=
<!-- relevant lists that this aircraft appears in: -->
|lists=
*[[List of aircraft engines]]
<!-- For aircraft engine articles.  Engines that are of similar to this design: -->
|similar engines=
*[[General Electric Passport]]
*[[Pratt & Whitney Canada PW800]]
<!-- See [[WP:Air/PC]] for more explanation of these fields. -->
}}

==References==
{{Reflist|30em}}

==External links==
{{Commons category}}
* {{official website|http://www.safran-aircraft-engines.com/commercial-engines/business-jet/silvercrestr}}
* {{cite video |url= http://www.ainonline.com/aviation-news/video/safrans-move-business-aviation-back-track-silvercrest-engine |title= Safran's Move Into Business Aviation is Back on Track With Silvercrest Engine |date= November 9, 2016 |work= Aviation International News}}

{{Snecma aeroengines}}

[[Category:High-bypass turbofan engines]]
[[Category:2010s turbofan engines]]
[[Category:Snecma aircraft engines|Silvercrest]]