Developed in 1949, the K-225 is the same as the Kaman K-190 except for engine and performance.  CAA certificated, 11 were produced with the primary use of crop dusting.  In March 1950, three K-225s were delivered to the United States Navy and Coast Guard for evaluation.  Of those delivered, the K-225 performed the first loop by a helicopter.  The Navy took the K-225 into service, modifying it under the designation of HTK-1. This version used a reciprating engine.

Source:  Hirschberg, Michael. "The American Helicopter" (2000). Page 58.


Data on design, manufacture and status

Design authority: Kaman Aircraft Corporation

Primary manufacturer: Kaman Aircraft Corporation

Parent type: Kaman K-225

Aircraft status: No longer flying


Primary flight and mechanical characteristics

VTOL type: Helicopter

Lift configuration: Synchropter (x2)

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: 7.01 m 23.0 ft
Airframe Width:  
Airframe Height: 3.35 m 11.0 ft
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

Cruise Speed: 65 mph (105 km/h)

Max Gross Weight (ground): 1,225 kg 2,700 lb
Max Gross Weight (airborne):  
Max Take-off Weight: 1,225 kg 2,700 lb
Empty Weight: 816 kg 1,799 lb
Useful Load: 409 kg 901 lb
Empty Weight Fraction: 0.666
Climb Performance
Max Rate of Climb: 5 m/s 1,000 fpm
Hover Performance
Hover Ceiling IGE:  
Hover Ceiling OGE:  
Max Level Flight Speed:  
Never Exceed Speed:  
Service Ceiling: 3,658 m 12,001 ft
Range and Endurance
Max Range: 312 km 168 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: Lycoming O-435-A2 reciprocating
Manufacturer: Lycoming Engines
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 Characteristics
Diameter: 11.58 m 37.99 ft
Direction of Rotation: Counter-rotating
Hub Type:
Main Rotor Blade Characteristics
Blade Construction: Solid Wood
Blade Chord:  
Blade Tip Geometry:
Blade Twist:  
Number of Blades: 2
Main Rotor Derived Characteristics
Disc Area: 105.32 m² 1133.7 ft²
Disc Loading: 5.81 kg/m² 1.191 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
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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