西科斯基 X2

Sirkosky X2
Sikorsky X2
概觀
類型實驗複合直升機
代號X-2
乘員2人
首飛2008年8月27日
退役2011年7月14日
生產塞考斯基飛機公司
產量1
現況已退役
主要用戶美國陸軍
衍生機型賽考斯基S-97襲擊者直升機[1]
SB-1傲視者直升機
技术数据
空重5,300lb(2,404kg)[2]
負載重量6,000lb(2,722kg)[3][4][5]
最大起飛重量5,300lb(2,404kg)[6][7]
發動機1具LHTEC英语LHTECT800-LHT-801英语LHTEC T800渦輪軸發動機
推力1,800shp(1,300kW)
性能數據
最大速度290mph(460km/h,250kn)[8]
最大航程35mi(56km,30nmi)

西科斯基 X2[9] (英語:Sirkosky X2)是一架由塞考斯基飛機公司研製的實驗性同軸旋翼高速復合直升機,2008年首飛,2011年正式退役。

發展

西科斯基開發X2的預算為5000萬美元,該設計整合幾個早期設計項目中累積的技術。S-69/XH-59A證明使用兩個噴氣發動機提供輔助推進的同軸直升機可以實現高速行駛,但同時機身振動過大和油耗過高。[10][11][12]Cypher UAV英语Sikorsky Cypher電傳飛行器讓斯科斯基對同軸飛行的控制有新的見解,RAH-66卡曼契直升機則累積複合葉片和先進傳動設計方面的專業知識。[13][14]

其他積累的技術包括減慢[15]「消旋」[16] 剛性旋翼相距兩英尺,受UH-60黑鷹直升機啟發的主動力反振動,[17] 以及在向前飛行時將大部分動力用於推進螺旋槳而不是葉片。[18]與直升機不同的是,高速所需的動力大於懸停動力,而飛行員單獨控制螺旋槳動力。

而在研發時,試飛和飛行模擬相同時進行,以改進測試程序。[19][20]電傳飛行系統由霍尼韋爾提供,旋翼由鹰之航集团(Eagle Aviation Technologies)提供,抗震技術由穆格公司英语Moog Inc.提供,螺旋槳由 Aero Composites 提供。[9]由於旋翼轂的阻力是葉片的10-20倍,[21]西科斯基打算測試旋翼轂整流罩以減少40%的阻力,[22]並在輪轂本身上測試飛行的整流罩,而不是旋翼轂之間的中央旋翼整流罩。[23]此後,西科斯基獲得了適用於中央輪轂整流罩的“豎管”(旋轉葉片軸之間的固定管)專利。[23][24]

2009年5月4日,西科斯基推出了X2的輕型武裝直升機版本,[25] 並於2014年10月推出了原型機。[26][27][28]

2014年6月,西科斯基/波音聯合提交基於X2基礎,而衍伸的未來垂直起降載具英语Future Vertical Lift(FVL)的SB-1傲視者直升機[26][27],並於10月獲得陸軍批准。[28]

歷史

X2於2008年8月27日在在紐約霍斯黑茲Schweizer Aircraft英语Schweizer Aircraft首飛。該飛行持續了30分鐘。[29] 該次飛行為一個四階段的飛行測試,並最終達到計劃的 250 節最高速度。[30]X2於2009年7月在其螺旋槳完全接合的情況下完成了飛行。[31]2010年5月下旬,西科斯基完成了測試的第三階段,X2在試飛中達到了181節。[32]

2010年7月26日,西科斯基宣布X2在佛羅里達州西棕櫚灘的飛行測試中超過225節(259英里/小時;417公里/小時),非正式地超過在1986年由改裝過的韋斯特蘭山貓直升機創造的國際航空聯盟旋翼飛機世界速度紀錄216節(249英里/小時;400公里/小時)。[33][34]

2010年9月15日,試飛員Kevin Bredenbeck以250節(290英里/小時;460公里/小時)的速度平飛,達到了西科斯基X2的設計目標,[35][36] 創造了非官方速度記錄一架直升機。[10][37]並且,-2在2˚至3˚的淺俯衝中達到了260節(300 英里/小時;480 公里/小時)的新紀錄速度,[38]僅低於西科斯基 S-69達到的303英里/小時。[39] X2的噪音也很小,據稱在200節時的噪音水平與普通直升機在100節時的噪音水平相同。 在200節以上,旋翼速度從446降低到360RPM[40][6],以保持葉尖速度低於0.9馬赫,旋翼盤略微抬頭,升阻比約為一架傳統的直升機,並在飛行測試期間也成功地進行了不干涉飛行。[41]

2011年7月14日,X2完成最後一次飛行,在23次試飛共計飛行22小時後正式退役。[42][43]X-2於 2016年10月捐贈給美国国家航空航天博物馆,並在弗吉尼亞州尚蒂利英语Chantilly, Virginia史蒂文·烏德沃爾哈齊中心展出。[2][44]

參考

  1. ^ "Award-Winning X2 Technology Demonstrator Takes its Final Flight - Program paved the way for upcoming S-97 Raider helicopter"页面存档备份,存于互联网档案馆), Sikorsky Aircraft Corp., 14 July 2011.
  2. ^ 2.0 2.1 Connor, Roger. Sikorsky X2 Helicopter Reaching New Speeds. National Air and Space Museum. 25 October 2016 [5 December 2016]. (原始内容存档于16 May 2020) (英语). Weight, empty: 2,404 kg (5,300 lb) 
  3. ^ Johnson, Wayne. Design and Performance of Lift-Offset Rotorcraft for Short-Haul Missions (PDF). NASA: 4. January 18–20, 2012 [2023-03-20]. (原始内容存档 (PDF)于2023-03-20). nominal gross weight of 5950 lb. 
  4. ^ Drew, James. ANALYSIS: Sikorsky seeks next leap in rotorcraft technology. Flight Global. 2016-02-19. (原始内容存档于30 August 2020) (英语). We started with [the] X2 technology demonstrator at about 6,000lbs (2.7t) gross weight. 
  5. ^ Walsh, D. High airspeed testing of the Sikorsky X2 Technology™ demonstrator. January 2011. 
  6. ^ 6.0 6.1 Jackson, Dave. "Coaxial - Sikorsky ~ X2 TD" Unicopter, 18 September 2010. Accessed: April 2014. Archived on 13 September 2013.
  7. ^ Tomkins, Richard. "Sikorsky powers on S-97 avionics" United Press International, 17 June 2014. Accessed: 19 June 2014. Archived on 18 June 2014.
  8. ^ Sikorsky X2 Technology™ Demonstrator Achieves 250-Knot Speed Milestone. [2023-03-20]. (原始内容存档于2023-03-20). 
  9. ^ 9.0 9.1 Sikorsky X2. Flug-Revue. [2007-06-25]. (原始内容存档于June 12, 2008). 
  10. ^ 10.0 10.1 Goodier, Rob. Inside Sikorsky's Speed-Record-Breaking Helicopter Technology. Popular Mechanics. September 20, 2010 [22 September 2010]. (原始内容存档于2011-06-29). 
  11. ^ Thomas Lawrence and David Jenney. The Fastest Helicopter on Earth. IEEE Spectrum. 31 Aug 2010 [1 August 2017]. (原始内容存档于30 January 2017). the helicopter vibrated so much at these higher speeds that its pilots struggled to control it .. The heavy and fuel-hungry jets pushed the aircraft to high speed 
  12. ^ XH-59A / X2 comparison页面存档备份,存于互联网档案馆IEEE
  13. ^ Sikorsky to Build and Test X2 Technology Demonstrator Helicopter 互联网档案馆存檔,存档日期July 14, 2008,.. Sikorsky
  14. ^ Trimble, Stephen. Sikorsky X2 sets unofficial helicopter speed record. FlightGlobal. Reed Business Information. 26 July 2010 [29 July 2010]. (原始内容存档于2010-07-30). 
  15. ^ First Flight Of Sikorsky X2 Demonstrator, 互联网档案馆存檔,存档日期March 7, 2012,. Aviation Week & Space Technology, 27 August 2008. Accessed: 9 March 2012. Archived on 7 March 2012.
  16. ^ Chandler, Jay. "Advanced rotor designs break conventional helicopter speed restrictions (page 1) 互联网档案馆存檔,存档日期July 18, 2013,." Page 2 互联网档案馆存檔,存档日期July 18, 2013,. Page 3 互联网档案馆存檔,存档日期2013-07-18.. ProPilotMag, September 2012. Accessed: 10 May 2014. Archive 1 Archive 2
  17. ^ X2 marks the spot for radical rotor designs页面存档备份,存于互联网档案馆), Flightglobal.com, 12 June 2007.
  18. ^ Fell, William. X2 From the Pilot's View. digitaledition.rotorandwing.com. April–May 2018. (原始内容存档于8 May 2019). 
  19. ^ Wilson, J.R. "Defense Interview: Mark Miller" Defense Media Network, 9 September 2011. Accessed: 4 October 2014. Archived on 2 November 2012.
  20. ^ "Sikorsky Innovations Introduces X2 Technology™ Light Tactical Helicopter Simulator页面存档备份,存于互联网档案馆)" Sikorsky PR
  21. ^ Harris, Franklin D. "Rotor Performance at High Advance Ratio: Theory versus Test 互联网档案馆存檔,存档日期2013-02-18." page 119 NASA/CR—2008–215370, October 2008. Accessed: 13 April 2014.
  22. ^ Croft, John. Sikorsky X2 breaks helicopter speed barrier. Flightglobal (Reed Business Information). 20 May 2010 [28 May 2015]. (原始内容存档于28 May 2015). 
  23. ^ 23.0 23.1 Dubois, Thierry. AgustaWestland. Aviation International News. 26 July 2011 [28 May 2015]. (原始内容存档于11 October 2014). 
  24. ^ US 20150125299  "Counter-rotating Rotor System With Stationary Standpipe" PDF页面存档备份,存于互联网档案馆
  25. ^ Trimble, Stephen. Sikorsky unveils mock-up X2 armed scout页面存档备份,存于互联网档案馆). Flightglobal.com, 4 May 2009.
  26. ^ 26.0 26.1 Majumdar, Dave. "Sikorsky and Boeing Team Submit New Army Helicopter Design" - News.USNI.org, 17 June 2014. Accessed: 19 June 2014. Archive
  27. ^ 27.0 27.1 Sikorsky and Boeing to pitch ‘X-2’-based design for US Army JMR TD effort页面存档备份,存于互联网档案馆) - Flightglobal.com, February 28, 2013
  28. ^ 28.0 28.1 U.S. Army Selects Bell and Sikorsky/Boeing to Build Prototypes for Next Generation Helicopter Program页面存档备份,存于互联网档案馆) - News.USNI.org, 3 October 2014
  29. ^ Trimble, Stephen. "Sikorsky's X2 speedster completes first flight". Flightglobal.com, 27 August 2008.
  30. ^ Trimble, Stephen. "Sikorsky high-speed X2 prototype starts flight-test phase"页面存档备份,存于互联网档案馆). Flight International, 2 September 2008.
  31. ^ Lynch, Kerry. "Sikorsky X2 Flies With Engaged Propeller"[失效連結] Aviation Week, 13 July 2009. Paywall
  32. ^ Croft, John. "Sikorsky completes third-phase X2 tests with 181kt flight"页面存档备份,存于互联网档案馆). Flight International, 27 May 2010.
  33. ^ "Rotorcraft Absolute: Speed over a straight 15/25 km course 互联网档案馆存檔,存档日期2013-12-03.". Fédération Aéronautique Internationale (FAI). Note search under E-1 Helicopters and "Speed over a straight 15/25 km course". Accessed: 26 April 2014.
  34. ^ "X2 Technology Demonstrator Achieves 225 Knots, Sets New Top Speed for Helicopter - Target Milestone of 250 Knots Looms in Q3 2010"页面存档备份,存于互联网档案馆). UTC.com, 15 June 2015.
  35. ^ Croft, John. Sikorsky X2 hits 250kt goal. Flight International. September 15, 2010 [2010-09-16]. (原始内容存档于2013-10-19). 
  36. ^ Varnon, Rob. Sikorsky's X2 chases world speed record. Connecticut Post. May 26, 2010 [2023-03-20]. (原始内容存档于2023-03-20). 
  37. ^ Sikorsky X2 Technology Demonstrator Achieves 250-Knot Speed Milestone. sikorsky.com. 15 September 2010 [23 September 2010]. (原始内容存档于14 October 2013). 
  38. ^ Finnegan, Joy editor-in-chief. Sikorsky Breaks 250 KTAS Record. Rotor & Wing. 1 October 2010 [6 October 2010]. (原始内容存档于2010-10-31). 
  39. ^ Robb, Raymond L. Hybrid Helicopters: Compounding the Quest for Speed[永久失效連結] p49, Vertiflite, Summer 2006. Quote: "Ultimately, the XH-59A achieved an incredible 303 mph"
  40. ^ Datta, Anubhav et al. Experimental Investigation and Fundamental Understanding of a Slowed UH-60A Rotor at High Advance Ratios页面存档备份,存于互联网档案馆, page 2. NASA, 2011. Accessed: April 2014.
  41. ^ D. Walsh, S. Weiner, K. Arifian, T. Lawrence, M. Wilson, T. Millott and R. Blackwell. "High Airspeed Testing of the Sikorsky X2 Technology Demonstrator[永久失效連結]" Sikorsky, May 4, 2011. Accessed: October 5, 2013.
  42. ^ Paur, Jason. Sikorsky's Record-Setting Helicopter Retires. WIRED. 15 July 2010 [15 July 2011]. (原始内容存档于2013-07-19). 
  43. ^ Sikorsky X2 rotorcraft prototype makes final flight after proving technology for S-97 scout/attack helicopter. www.militaryaerospace.com. 17 July 2011 [2023-03-20]. (原始内容存档于2021-02-04). 
  44. ^ Sikorsky X2 joins Smithsonian collection. Helicopter Association International. Helicopter Association International. 28 October 2016 [5 December 2016]. (原始内容存档于2016-12-20). 

外部連結

外部视频链接
Official Sikorsky X2 videos
video icon YouTube上的Sikorsky X2 technology, mitigating dissymmetry of lift and air compressibility near rotor blade tip
video icon YouTube上的Sikorsky X2 record flight in 2010
video icon YouTube上的Sikorsky X2 Collier Trophy, pilot and staff commentary

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This article needs to be updated. Please help update this article to reflect recent events or newly available information. (June 2024) Lower house of the Parliament of South Africa National Assembly Name in official languages Nasionale Vergadering (Afrikaans) iNdlu yesiBethamthetho seNarha (Southern Ndebele) iNdlu yoWiso-mthetho yeSizwe (Xhosa) iSishayamthetho sikaZwelonke (Zulu) liBandla laVelonkhe (Swazi) Seboka sa Maloko a Palamente (Northern Sotho) Ntlo ya Se...

2001 fire in Volendam, Netherlands Volendam New Year's fireRescue operations after the fireDate1 January 2001 (2001-01-01)LocationVolendam, NetherlandsCoordinates52°29′34.4″N 5°4′26.3″E / 52.492889°N 5.073972°E / 52.492889; 5.073972TypeFireDeaths14Non-fatal injuries241 The building in 2010 Monument for the victims of the New Year's fire on the Volendam dike, adjacent to the place where the fire happened Monument for the victims of the New Yea...

 

This article needs additional citations for verification. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed.Find sources: From Time to Time – The Singles Collection – news · newspapers · books · scholar · JSTOR (March 2007) (Learn how and when to remove this message) 1991 compilation album by Paul YoungFrom Time to Time – The Singles CollectionCompilation album by Pau...