Developed in 1943.  The helicopter can be modified from two-passenger capacity to four for the U.S. Coast Guard by replacing the fuel tanks with external ones.  Designated HOS-1 in the US Navy.


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: 1-2

Crew seating: Side-by-side

Landing gear: Wheels (non-retractable)

Layout and Dimensions

Data on aircraft size

Overall Dimensions
Overall Height: 3.53 m 11.6 ft
Overall Length: 14.61 m 47.9 ft
Overall Width: 11.58 m 38.0 ft
Airframe Dimensions
Airframe Length: 10.34 m 33.9 ft
Airframe Width:  
Airframe Height: 3.53 m 11.6 ft
Landing Gear Dimensions
Landing Gear Base: 3.12 m 10.3 ft
Landing Gear Track: 2.74 m 9.0 ft
Cabin Dimensions
Cabin Internal Height:  
Cabin Internal Length:  
Cabin Internal Width:  

Weights and Performance

Data on aircraft weight and flight characteristics

Cruise Speed: 75 mph (120.701 km/h)

Max Gross Weight (ground): 1,406 kg 3,100 lb
Max Gross Weight (airborne):  
Max Take-off Weight: 1,406 kg 3,100 lb
Empty Weight: 914 kg 2,016 lb
Useful Load: 492 kg 1,084 lb
Empty Weight Fraction: 0.650
Climb Performance
Max Rate of Climb: 4 m/s 801 fpm
Hover Performance
Hover Ceiling IGE:  
Hover Ceiling OGE:  
Max Level Flight Speed: 153 km/h 83 kts
Never Exceed Speed: 185 km/h 100 kts
Service Ceiling: 3,048 m 10,000 ft
Range and Endurance
Max Range: 644 km 348 nm
Max Endurance:  

Engine Details

Aircraft powerplant (lift and/or propulsion)

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

Number of engines: 1
Designation: Franklin O-405-9 reciprocating
Manufacturer: Franklin Engine Company
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

Main Rotor Characteristics
Diameter: 11.58 m 38.00 ft
Direction of Rotation: Counterclockwise
Hub Type: Fully articulated
Main Rotor Blade Characteristics
Blade Construction:
Blade Chord:  
Blade Tip Geometry:
Blade Twist:  
Number of Blades: 3
Main Rotor Derived Characteristics
Disc Area: 105.36 m² 1134.2 ft²
Disc Loading: 13.35 kg/m² 2.733 lb/ft²
Main Rotor Blade Derived Characteristics
Blade area per blade:  
Tip Speed:  

Primary Control Device

Data on primary control devices such as tail rotors

Tail Rotor Characteristics
Diameter: 2.50 m 8.21 ft
Configuration: Tractor
Direction of Rotation: Top blade aft
Tail Rotor Blade Characteristics
Number of Blades: 3
Blade Construction:  
Blade Chord:  
Blade Twist:  
Tail Rotor Derived Characteristics
Disc Area: 4.92 m² 52.9 ft²
Tail Rotor Blade Derived Characteristics
Tip Speed:  
Blade Area (per blade):  

Related VFS Resources

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Related Public Resources

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