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Bell ARH-70 Arapaho

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ARH-70 Arapaho
An ARH-70 Arapaho
General information
TypeReconnaissance armed helicopter
ManufacturerBell Helicopter
StatusCanceled
Number builtFour (prototypes)
History
First flight20 July 2006
Developed fromBell 407

The Bell ARH-70 Arapaho[1][2] was an American four-bladed, single-engine, light military helicopter designed for the United States Army's Armed Reconnaissance Helicopter (ARH) program. With a crew of two and optimized for urban combat, the ARH-70 was slated to replace the Army's aging OH-58D Kiowa Warrior.

Excessive delays and growth in program costs forced its cancellation on 16 October 2008, when the Department of Defense failed to certify the program to Congress. The ARH-70 was touted as having been built with off-the-shelf technology, the airframe being based on the Bell 407 (and as such was related to the OH-58).

Development

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Background and Armed Reconnaissance Helicopter competition

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The RAH-66 Comanche helicopter program was canceled by the U.S. Army on 23 February 2004. The cancellation was a result of a six-month study which recommended canceling the program before the Comanche reached production, after 20 years and development costs of over US$6.9 billion. The study estimated that the Army would save US$14 billion with the cancellation, which could then be used to update and replace the aging airframes of the Army's helicopter fleet.[3] The study targeted the OH-58D Kiowa Warrior for replacement based on the age of the airframes, recent losses, and a lack of replacement airframes.

Army officials issued a request for proposals (RFP) for the replacement aircraft as the Armed Reconnaissance Helicopter (ARH) on 9 December 2004.[4] The Army's concept would use commercial off-the-shelf (COTS) technology, with the goal of an operational unit of 30 helicopters and eight trainers ready by September 2008.[5] Two companies submitted bids:[6]

A Bell 407 being used for early development of the ARH-70

The Army announced Bell as the winner of a contract for 368 helicopters on 29 July 2005. There was some confusion as Bell figures placed the contract value at US$2.2 billion while Army estimates were over US$3 billion, compared to its earlier estimate of US$2.36 billion.[10] The contract called for the development of prototypes and the delivery of preproduction aircraft to the Army for the Limited User Test (LUT), with the first unit equipped by the end of September 2008.[5][11]

Flight testing

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Unarmed training prototype in January 2008

Bell's ARH demonstrator, a modified Bell 407 (s/n 53343/N91796[12]), first flew on 3 June 2005.[13] In February 2006, the ARH demonstrator flew with a limited avionics and Mission Equipment Package (MEP), and in April Bell fitted and mounted the Honeywell HTS900-2 engine to the demonstrator airframe, followed by a series of ground runs.[14] The first flight was delayed, first in March and then in May, to allow Bell to configure the prototypes as preproduction aircraft. Bell and the Army both eventually agreed that this delay would be essential for maintaining the compressed timeline for development.[14] The ARH-70's maiden flight occurred on 20 July 2006, at Bell's XworX facility in Arlington, Texas.[5]

On 21 February 2007, during its first flight, prototype #4 (s/n 53906/N445HR) suffered a loss of engine power, due to fuel starvation, and made an autorotational landing at a nearby golf course. The aircraft was damaged beyond repair when it rolled over during the landing; the test pilots survived and were uninjured.[15][16][17]

Program cost increases and cancellation

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A month later, on 22 March 2007, the Army issued a "Stop Work" notice, giving Bell 30 days to present a plan to get the ARH program back on track. Previous estimates for the System Development Demonstration portion of the program had grown from $210 million to over $300 million.[18] Textron, Bell's parent company, notified investors that they could lose $2–4 million on each aircraft under the contract.[19] Bell appealed and received permission to continue development using company funds until the notice was resolved. On 18 May 2007, the Army approved continuation of the ARH program.[20]

The House Appropriations Committee's Defense panel drafted a bill for the 2008 Defense Budget which zeroed out funding for ARH-70 production, citing Bell's inability to enter production, but continued funding for research and development.[21] However, government officials began working on export policy to allow international sales of the ARH-70. Including the U.S. Army's expected total of 512 helicopters, orders were anticipated to total over 1,000.[22] The Army filed a Nunn-McCurdy cost and schedule breach on 9 July 2008, when new cost estimates showed a 40% cost increase above initial estimates. In August 2008, the Army requested that Bell cease recruitment for the ARH-70 program pending the outcome of the review.[23]

On 16 October 2008, the Army's Acquisition Executive Office for Aviation directed that the ARH contract be terminated completely for the convenience of the government.[24] The cancellation was the result of the United States Department of Defense (DOD) not certifying the US$6.2 billion ARH-70 program to Congress. John Young, the Undersecretary of Defense for Acquisition, Technology and Logistics, cited the reason as excessive costs of the program which had increased over 70 percent with an estimated per-unit cost of US$14.5 million, up from US$8.5 million.[25]

Although the ARH-70 was not procured by the USA, the Iraqi Air Force bought Bell 407 armed scouts in a similar configuration as the ARH starting in 2009.[26] There are 30 in service; 24 armed scouts, three gunships, and three trainers.[27]

Specifications (ARH-70)

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Data from Bell ARH-70,[28] Bell 407[29]'

General characteristics

  • Crew: two pilots
  • Capacity: six passengers and 1,868 lb (847 kg) useful load
  • Length: 34 ft 8 in (10.57 m)
  • Height: 11 ft 8 in (3.56 m)
  • Empty weight: 2,598 lb (1,178 kg)
  • Gross weight: 5,000 lb (2,268 kg)
  • Max takeoff weight: 5,000 lb (2,268 kg)
  • Powerplant: 1 × Honeywell HTS900-2 turboshaft, 970 shp (723 kW)
  • Main rotor diameter: 35 ft 0 in (10.67 m)
  • Main rotor area: 962 sq ft (89 m2)

Performance

  • Maximum speed: 140 kn (161 mph, 259 km/h)
  • Cruise speed: 113 kn (130 mph, 209 km/h)
  • Range: 162 nmi (186 mi, 300 km)
  • Service ceiling: 20,000 ft (6,096 m)

Armament

See also

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Related development

Aircraft of comparable role, configuration, and era

References

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  1. ^ "U.S. Army Happier With ARH-70A Program". Archived from the original on 5 November 2014. Retrieved 9 November 2010.
  2. ^ Aviation Modernization Program to Field Lakota, Modify Current Helos
  3. ^ Burlas, Joe. "Comanche project grounded" Archived 21 January 2009 at the Wayback Machine. Army News Service, 23 February 2004. Accessed on 17 October 2008.
  4. ^ "Armed Reconnaissance Helicopter (ARH)". Global Security. Accessed 1 October 2007.
  5. ^ a b c "ARH-70A First Flight!" Archived 17 July 2008 at the Wayback Machine. Bell Helicopter press release, 20 July 2006. Accessed 17 October 2008.
  6. ^ "Filling Comanche's Shoes" Archived 11 September 2016 at the Wayback Machine. Aviation Today
  7. ^ "Rotorcraft Report: Bell Beats Boeing, Aims for ARH Deliveries Next Year" Archived 28 September 2011 at the Wayback Machine. Rotor & Wing, September 2005. Accessed 17 October 2008.
  8. ^ Trimble, Stephen. "Bell and Boeing battle to win ARH". Flight International, 22 February 2005.
  9. ^ Warwick, Graham. "Bell launches Honeywell HTS900-powered 417 to rival Eurocopter Squirrel". Flight International, 27 February 2006.
  10. ^ "Bell defeats Boeing with 407 ARH". Flight International, 9 August 2005. Accessed 18 October 2008.
  11. ^ The Bell ARH-70A, Armed Reconnaissance Helicopter – Program Timeline Archived 9 May 2008 at the Wayback Machine. Bell Helicopter. Accessed 26 September 2010.
  12. ^ 407 airframe
  13. ^ "ARH debut". Flight International. 14 June 2005. Accessed 18 October 2008.
  14. ^ a b "Rotorcraft Report" Archived 28 September 2011 at the Wayback Machine. Rotor & Wing, April 2006. Accessed on 18 October 2008.
  15. ^ "NTSB Identification: DFW07CA066". factual report. National Transportation Safety Board. 29 May 2007. Accessed on 18 October 2008.
  16. ^ "ARH Crash: Foreign Objects Blocked Fuel Flow" Archived 28 September 2011 at the Wayback Machine. Rotor & Wing. Aviation Today. 29 March 2007. Accessed 17 October 2008.
  17. ^ "ARH Crash Probe Clears Engine, Cites Fuel Starvation" Archived 28 September 2011 at the Wayback Machine. Aviation Today, April 2008. Accessed 17 October 2008.
  18. ^ Warwick, Graham. "Work stops as soaring ARH cost alarms Army". Flight. 27 March 2007. Accessed on 28 June 2009.
  19. ^ "US Army orders Bell to stop work on ARH and come up with new plan". Flight International. Accessed 24 March 2007.
  20. ^ "Army to Continue with Bell Helicopter/Textron Inc. for Armed Reconnaissance Helicopter" Archived 13 June 2007 at the Wayback Machine. Army press release. United States Army. 18 May 2007.
  21. ^ United States House of Representatives. "Selected Cuts" Archived 8 August 2007 at the Wayback Machine. Summary: 2008 Defense Appropriations. United States House of Representatives, 2008. Accessed on 28 June 2009.
  22. ^ "Daily News: Army Requests Hundreds of ARH-70As" Archived 28 September 2011 at the Wayback Machine. Rotor & Wing magazine, 23 January 2008.
  23. ^ Bruno, Michael and Graham Warwick. "ARH Breaches Nunn-McCurdy Caps"[permanent dead link‍]. Aviation Week, 10 July 2008. Accessed 28 June 2009.
  24. ^ Army Press Service. "Armed Reconnaissance Helicopter program halted, need for capability remains". Army News. 17 October 2008. Accessed on 24 October 2008.
  25. ^ "Pentagon Cancels Armed Reconnaissance Helicopter"[dead link‍]. Defense News, 16 October 2008. Accessed 16 October 2008.
  26. ^ "Bell 407s Ordered for Iraq". Air International, April 2009, Vol 76, No. 4. p. 7.
  27. ^ "More For The Iraq Army Air Corps". Strategypage.com, January 29, 2013.
  28. ^ Bell ARH-70 page Archived 19 May 2007 at the Wayback Machine
  29. ^ Bell 407 specifications page Archived 2 March 2008 at the Wayback Machine
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