A longitudinal tandem rotor helicopter developed for the U.S. Navy as an Anti-submarine Warfare (ASW) hunter-killer.  The aircraft is equipped with folding rotors for storage and transportation.


Data on design, manufacture and status

Design authority: Bell Aircraft Corporation

Primary manufacturer: Bell Aircraft Corporation

Parent type: No type defined

Aircraft status: No longer flying


Primary flight and mechanical characteristics

VTOL type: Helicopter

Lift configuration: Tandem (Fore/aft) (x2)

Crew required: 4

Crew seating: Tandem

Landing gear: Wheels (non-retractable)

Layout and Dimensions

Data on aircraft size

Overall Dimensions
Overall Height: 4.42 m 14.5 ft
Overall Length: 27.14 m 89.0 ft
Overall Width: 15.70 m 51.5 ft
Airframe Dimensions
Airframe Length: 12.19 m 40.0 ft
Airframe Width: 3.57 m 11.7 ft
Airframe Height: 4.42 m 14.5 ft
Landing Gear Dimensions
Landing Gear Base: 4.71 m 15.5 ft
Landing Gear Track: 3.37 m 11.0 ft
Cabin Dimensions
Cabin Internal Height:  
Cabin Internal Length:  
Cabin Internal Width:  

Weights and Performance

Data on aircraft weight and flight characteristics

Cruise Speed: 100 mph (160.934 km/h)

Max Gross Weight (ground): 7,620 kg 16,800 lb
Max Gross Weight (airborne):  
Max Take-off Weight: 7,620 kg 16,800 lb
Empty Weight: 5,648 kg 12,451 lb
Useful Load: 1,973 kg 4,349 lb
Empty Weight Fraction: 0.741
Climb Performance
Max Rate of Climb: 8 m/s 1,475 fpm
Hover Performance
Hover Ceiling IGE:  
Hover Ceiling OGE: 3,018 m 9,900 ft
Max Level Flight Speed:  
Never Exceed Speed: 185 km/h 100 kts
Service Ceiling: 4,389 m 14,400 ft
Range and Endurance
Max Range: 556 km 300 nm
Max Endurance: 3 hrs 3 hrs

Engine Details

Aircraft powerplant (lift and/or propulsion)

Provided powerplant data is for uninstalled, sea level, static operations.

Number of engines: 1
Designation: P&W R-2800-50 reciprocating
Manufacturer: Pratt & Whitney
Normal Ratings
Max continuous:  
Take-off / rated: 1417 kW 1899 hp
OEI Ratings
OEI contingency:  
OEI continuous:  
OEI 30-second:  
OEI intermediate:  

Primary Lift Device

Data on primary lift devices such as main rotors

Airfoil sections: NACA 001815 at root, NACA 00099 at tip Fwd rotor rotates clockwise (viewed from top), aft rotor anti-clockwise

Main Rotor Characteristics
Diameter: 15.70 m 51.50 ft
RPM: 289.3 rpm 289.3 rpm
Direction of Rotation: Counter-rotating
Hub Type: Teetering with flapping stops
Main Rotor Blade Characteristics
Blade Construction: Laminated wood with fiberglass cloth covering and stainless steel erosion strip on leading edge
Blade Chord: 0.686 m 2.25 ft
Blade Tip Geometry: Conventional
Blade Twist: -0.105 rad -6.000 deg
Number of Blades: 2
Main Rotor Derived Characteristics
Disc Area: 193.52 m² 2083.1 ft²
Disc Loading: 19.69 kg/m² 4.033 lb/ft²
Solidity: 0.0556
Main Rotor Blade Derived Characteristics
Blade area per blade: 5.38 m² 57.9 ft²
Tip Speed: 237.74 m/s 780.0 fps

Primary Control Device

Data on primary control devices such as tail rotors

Tail Rotor Characteristics
Configuration: Unknown
Direction of Rotation: Unknown
Tail Rotor Blade Characteristics
Number of Blades:  
Blade Construction: N/A
Blade Chord:  
Blade Twist:  
Tail Rotor Derived Characteristics
Disc Area:  
Tail Rotor Blade Derived Characteristics
Tip Speed:  
Blade Area (per blade):  

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Related Public Resources

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