Intial company prototype for the HRP-1 Type series. It was also designated PV-3 by the company.

An excellent description of the design and development of the aircraft can be found on the Smithsonian National Air and Space Museum web site,

"P-V Engineering Forum XHRP-X (PV-3)", R. D. Connor, Smithsonian National Air and Space Museum web page, Last accessed 04 November 2018


Data on design, manufacture and status

Latest or last design authority: Piasecki Helicopter Corporation
Originally designed by P-V Engineering Forum

Primary manufacturer: P-V Engineering Forum

Parent type: Piasecki PV-3/HRP-1

Aircraft status: No longer flying


Primary flight and mechanical characteristics

VTOL type: Helicopter

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

Crew required: 2

Crew seating: Other

Landing gear: Wheels (non-retractable)

Layout and Dimensions

Data on aircraft size

Overall Dimensions
Overall Height: 4.15 m 13.6 ft
Overall Length: 25.70 m 84.3 ft
Overall Width: 12.50 m 41.0 ft
Airframe Dimensions
Airframe Length: 14.41 m 47.3 ft
Airframe Width:  
Airframe Height: 4.15 m 13.6 ft
Landing Gear Dimensions
Landing Gear Base: 4.94 m 16.2 ft
Landing Gear Track: 3.05 m 10.0 ft
Cabin Dimensions
Cabin Internal Height:  
Cabin Internal Length:  
Cabin Internal Width:  

Weights and Performance

Data on aircraft weight and flight characteristics

Cruise Speed: 80 mph (128.748 km/h)

Max Gross Weight (ground):  
Max Gross Weight (airborne):  
Max Take-off Weight:  
Empty Weight:  
Useful Load:  
Empty Weight Fraction:  
Climb Performance
Max Rate of Climb: 5 m/s 950 fpm
Hover Performance
Hover Ceiling IGE:  
Hover Ceiling OGE:  
Max Level Flight Speed: 161 km/h 87 kts
Never Exceed Speed:  
Service Ceiling: 3,170 m 10,400 ft
Range and Endurance
Max Range:  
Max Endurance:  

Engine Details

Aircraft powerplant (lift and/or propulsion)

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

Number of engines: 1
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

Blades have NACA 0012 section

Main Rotor Characteristics
Diameter: 12.50 m 41.00 ft
RPM: 250.0 rpm 250.0 rpm
Direction of Rotation: Counter-rotating
Hub Type:
Main Rotor Blade Characteristics
Blade Construction:
Blade Chord: 0.335 m 1.10 ft
Blade Tip Geometry: Tapering chord in outer tip region
Blade Twist:  
Number of Blades: 3
Main Rotor Derived Characteristics
Disc Area: 122.66 m² 1320.3 ft²
Disc Loading:  
Solidity: 0.0511
Main Rotor Blade Derived Characteristics
Blade area per blade: 2.09 m² 22.5 ft²
Tip Speed: 163.58 m/s 536.7 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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