Boeing/Sikorsky RAH-66 Comanche

Type (Muster)
Scout/attack helicopter (Aufklärungs- und Kampfhubschrauber)

Country (Land)
USA

Manufacturer (Hersteller)
Boeing (Helicopters)
PO Box 16858
Philadelphia, Pennsylvania 19142
USA
Phone: 001-610/591-2700
Fax: 001-610/591-2701

Sikorsky Aircraft
6900 Main Street
Stratford, Connecticut 06497
USA
Phone: 001-203/386-4000
Fax: 001-203/386-7300

Joint Program Office established at Trumbull (Connecticut) in 1992

General (Allgemeine Angaben)
Crew (Besatzung): 2 in tandem

Armament (Bewaffnung): A Lockheed Martin three barrel 20 mm cannon with 320 to 500 rounds is fitted in an undernose turret.
The enclosed weapons bays on each side of the fuselage have a total of six hardpoints. These can take six Hellfire or 12 Stinger missiles or Hydra 70 rocket launchers or four tube lightweight rocket pods.
In an alternate configuration, stub wings can be fitted for an additional eight Hellfires or eight Stingers or 870 liter fuel tanks.

Power plant (Antrieb): 2 x LHTEC T800-LHT-801 turboshafts
Power (Leistung): 2 x 690 kW (925 shp) at 4000 ft, but transmission rated at 1532 kW (2054 shp). A boost to 1164 kW (1563 shp) with a transmission rated at 1639 kW is planned.

Dimensions (Abmessungen)
Fuselage length (Rumpflänge): 13,22 m
Length overall, rotor turning (Länge über drehenden Rotor): 14,28 m
Height (Höhe): 3,39 m
Max. fuselage width (Rumpfbreite): 2,04 m
Tailplane span (Spannweite des Höhenleitwerks): 2,82 m
Main rotor diameter (Hauptrotordurchmesser): 11,90 m
Fantail diameter (Heckrotordurchmesser): 1,37 m
Main rotor disk (Hauptrotorkreisfläche): 111,2 sq m

Weights (Massen)
Empty weight (Leermasse): 3940 kg
Max. useful load (max. Zuladung): 1284 kg at primary mission, 2296 kg at max. gross weight
Max. fuel (Max. Kraftstoff): 1415 litres plus four external tanks totalling 3407 litres
Max. take-off weight (Max. Startmasse): 4807 kg for normal mission, 5819 kg maximum or 7896 kg overload for self deployment

Performance (Flugleistungen)
Max. level speed (Höchstgeschwindigkeit): 324 km/h at 1220 m
Cruising speed (Marschgeschwindigkeit): 306 km/h
Vertical rate of climb (Steigrate): 6 m/s
180 deg hover turn to target (180-Grad-Drehung im Schwebeflug): 4,7 sec
Ferry range (Überführungsreichweite): 2335 km with external tanks
Endurance (Einsatzdauer): 2 h 30 min
Load factor (g-Limits): +3,5/-1 g

Costs (Kosten)
Estimated programme unit cost of 26 million US-Dollars at 1997 values.
Total expenditures for the Comanche programme is now stated as 34 billion US-Dollars, though the figures are difficult to track due to various programme restructurings. 2,24 billion were spent on development between 1993 and 1997.
The Engineering and Manufacturing Development (EMD) phase, due to start in the summer of 2000, is prized at 3,1 billion US-Dollars.

Customers (Kunden)
The US Army has stated a need for 1213 helicopters in its aviation modernization plan of April 2000. This could be changed however, depending of funding levels and force structure plans at the time production start needs to be decided in a few years.

Competitors (Konkurrenz)
Eurocopter Tiger
Bell AH-1W Super Cobra
Kamow Ka-50

Remarks (Bemerkungen)
The RAH-66 Comanche is billed as the "quarterback of the digital battlefield" of the future. It features a fully composite airframe , shaped and treated for minimum radar signature and very good infrared suppression of the engine exhaust. It carries its armament internally and has a retractable landing gear. Equipment will include the Longbow radar of the AH-64D Apache in a miniaturized version.

History (Geschichte)
First concepts for a Light Helicopter Experimental (LHX) were pursued by the US Army at the beginning of the 80s. A request for proposals was finally issued in June 1988. Both Boeing/Sikorsky ("First Team") and Bell/McDonnell Douglas ("Super Team") were issued demonstration/validation contracts.
On 5 April 1991, the Boeing/Sikorsky team was announced winner of the development contract, to build four (later reduced to two) YRAH-66 prototypes, a static test article and a propulsion system testbed. Critical design review completed in December 1993, by which time first parts for prototypes were under construction. Roll-out ceremonies were held on 25 May 1995 at Sikorsky's Stratford plant. Following transport to the Development Flight Test Center at West Palm Beach (Florida), the first flight took place on 4 January 1996. It lasted 36 minutes.
A transmission gear failure on the ground testbed delayed the second flight to 24 August 1996, and the pace of flight tests has remained slow, mainly due to very low funding profile. By September 1998, there were about 105 flight hours in the logbook. Forward speeds of 320 km/h had been reached, as well as rearward speeds st up to 70 kts, 75 kts to the left and 65 kts to the right.
The second helicopter was completed in 1998 and shown at the Farnborough Air Show in September of that year. It flew for the first time on 30 March 1999 at West Palm Beach. In 30 minutes, the helicopter performed basic manoeuvres, forward flight up to 80 knots, and climbed to about 500 feet. Test pilots were Reggie Murrell and John Armbrust from the US Army.
On April 23, 1999. both Comanche prototypes flew together for the first time. In August, Boeing and Sikorsky delivered a 3,1 billion proposal for the EMD phase (Engineering and Manufacturing Development). This was contingent on the successful completion of the Milestone II review by the Pentagon, demanding fulfillment of various performance and development criteria. The Defense Acquisition Board gave its green light on 4 April 2000, leading the way to EMD contract signature in the summer of 2000.
By May 2000, the first prototpye had completed 174 flights (201,5 hours), while prototype 2s tally was 24 flights (21,9 hours).
During EMD, five more Comanches will be built for testing. They will fly from the spring of 2004. In total 2900 hours are planned. Eight more RAH-66 will be delivered to the Army for operational test and evaluation in 2004/2005. A low-rate initial production decision could come in June 2005, so that first series deliveries are possible in December 2006. Full rate production of 72 Comanches a year is planned for 2010.

Last updated 10 May 2000

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