This aircraft apparently had 2 or more control rotors but it is not clear how they were configured and what their exact purpose was. The original configuration also included secondary rotors to cool the engine but these were deemed ineffective.

de Bothezat's patent for the machine is US Patent 1,573,228.


Data on design, manufacture and status

Design authority: George de Bothezat

Primary manufacturer: George de Bothezat

Parent type: No type defined

Aircraft status: No longer flying


Primary flight and mechanical characteristics

VTOL type: Helicopter

Lift configuration: Multi-rotor (x4)

Crew required: 1

Crew seating: Single seater

Landing gear: Wheels (non-retractable)

Layout and Dimensions

Data on aircraft size

Overall Dimensions
Overall Height:  
Overall Length:  
Overall Width:  
Airframe Dimensions
Airframe Length:  
Airframe Width:  
Airframe Height:  
Landing Gear Dimensions
Landing Gear Base:  
Landing Gear Track:  
Cabin Dimensions
Cabin Internal Height:  
Cabin Internal Length:  
Cabin Internal Width:  

Weights and Performance

Data on aircraft weight and flight characteristics

Max Gross Weight (ground): 1,678 kg 3,700 lb
Max Gross Weight (airborne):  
Max Take-off Weight: 1,678 kg 3,700 lb
Empty Weight: 1,544 kg 3,404 lb
Useful Load: 134 kg 296 lb
Empty Weight Fraction: 0.920
Climb Performance
Max Rate of Climb:  
Hover Performance
Hover Ceiling IGE:  
Hover Ceiling OGE:  
Max Level Flight Speed:  
Never Exceed Speed:  
Service Ceiling:  
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
Designation: Bentley BR2 reciprocating
Manufacturer: Bentley and Bentley
Normal Ratings
Max continuous:  
Take-off / rated: 164 kW 220 hp
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 solidity is calculated using the tip chord

Main Rotor Characteristics
Diameter: 8.08 m 26.50 ft
RPM: 90.0 rpm 90.0 rpm
Direction of Rotation: Not applicable
Hub Type:
Main Rotor Blade Characteristics
Blade Construction:
Blade Chord: 1.524 m 5.00 ft
Blade Tip Geometry: Conventional
Blade Twist:  
Number of Blades: 6
Main Rotor Derived Characteristics
Disc Area: 51.24 m² 551.6 ft²
Disc Loading: 8.19 kg/m² 1.677 lb/ft²
Solidity: 0.7207
Main Rotor Blade Derived Characteristics
Blade area per blade: 6.15 m² 66.3 ft²
Tip Speed: 38.06 m/s 124.9 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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