USMC utility transport helicopter developed in 1953. The original designation was HR2S-1 but this was changed to CH-37C in the redesignation of all US armed forces helicopters in 1962.


The assault transport helicopter could carry up to either 36 passengers, three jeeps or a single 105 mm antitank gun.  Sikorsky was experimenting with blades widths; the wider chord upgrade was used for this entry.




Data on design, manufacture and status


Primary flight and mechanical characteristics

VTOL type: Helicopter

Lift configuration: Single main rotor

Dedicated control device: Tail rotor

Crew required: 2

Crew seating: Side-by-side

Landing gear: Wheels (all retractable)

Layout and Dimensions

Data on aircraft size

Overall Dimensions
Overall Height: 6.71 m 22.0 ft
Overall Length: 26.82 m 88.0 ft
Overall Width: 21.95 m 72.0 ft
Airframe Dimensions
Airframe Length: 19.78 m 64.9 ft
Airframe Width: 8.33 m 27.3 ft
Airframe Height: 5.42 m 17.8 ft
Landing Gear Dimensions
Landing Gear Base: 11.25 m 36.9 ft
Landing Gear Track: 5.80 m 19.0 ft
Cabin Dimensions
Cabin Internal Height:  
Cabin Internal Length:  
Cabin Internal Width:  

Weights and Performance

Data on aircraft weight and flight characteristics

Cruise Speed: 115 mph (185.075 km/h)

Max Gross Weight (ground): 14,061 kg 31,000 lb
Max Gross Weight (airborne):  
Max Take-off Weight: 14,061 kg 31,000 lb
Empty Weight: 9,385 kg 20,690 lb
Useful Load: 4,677 kg 10,310 lb
Empty Weight Fraction: 0.667
Climb Performance
Max Rate of Climb: 9 m/s 1,705 fpm
Hover Performance
Hover Ceiling IGE:  
Hover Ceiling OGE:  
Max Level Flight Speed: 209 km/h 113 kts
Never Exceed Speed:  
Service Ceiling: 2,652 m 8,700 ft
Range and Endurance
Max Range: 322 km 174 nm
Max Endurance:  

Engine Details

Aircraft powerplant (lift and/or propulsion)

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

Number of engines: 2
Designation: P&W R-2800-54 reciprocating
Manufacturer: Pratt & Whitney
Normal Ratings
Max continuous:  
Take-off / rated:  
OEI Ratings
OEI contingency:  
OEI continuous:  
OEI 30-second:  
OEI intermediate:  

Primary Lift Device

Data on primary lift devices such as main rotors

Notes: Wide Chord blades; RPM is the maximum.

Main Rotor Characteristics
Diameter: 21.95 m 72.00 ft
RPM: 204.0 rpm 204.0 rpm
Direction of Rotation: Counterclockwise
Hub Type: Fully articulated
Main Rotor Blade Characteristics
Blade Construction: All-metal
Blade Chord: 0.601 m 1.97 ft
Blade Tip Geometry: Conventional
Blade Twist: -0.140 rad -8.000 deg
Number of Blades: 5
Main Rotor Derived Characteristics
Disc Area: 378.25 m² 4071.6 ft²
Disc Loading: 37.17 kg/m² 7.614 lb/ft²
Solidity: 0.0871
Main Rotor Blade Derived Characteristics
Blade area per blade: 6.59 m² 71.0 ft²
Tip Speed: 234.41 m/s 769.1 fps

Primary Control Device

Data on primary control devices such as tail rotors

Tail Rotor Characteristics
Diameter: 4.57 m 15.00 ft
Configuration: Pusher
Direction of Rotation: Top blade fwd
Tail Rotor Blade Characteristics
Number of Blades: 4
Blade Construction: All-metal
Blade Chord:  
Blade Twist:  
Tail Rotor Derived Characteristics
Disc Area: 16.42 m² 176.7 ft²
Tail Rotor Blade Derived Characteristics
Tip Speed:  
Blade Area (per blade):  

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