Kaman K-225

Kaman Corporation · United States · first flew 1947 · helicopter

The Kaman K-225 was one of the world's first successful intermeshing-rotor helicopters, featuring two rotors mounted on outward-canting masts that mesh together without collision. It pioneered the servo-flap rotor control system that became a Kaman hallmark.

Recognition (WEFT)

W — Wings	High-mounted, rotary
E — Engines	1 × piston, fuselage-mounted
F — Fuselage	12.19 m fuselage
T — Tail	No tailplane

WEFT is AircraftIQ's four-point recognition method — how it works.

Spot it by:

Intermeshing synchropter twin-rotor helicopter
No tail rotor — two rotors mesh in eggbeater configuration
Early Kaman design with servo-flap rotor control

The crossed intermeshing two-bladed rotors on angled masts are unmistakable — no other layout looks quite like it. The absence of a tail rotor and the open girder tailboom are additional identifying features.

Specifications

The Kaman K-225 has a length of 12.19 m (40 ft).
It has a wingspan of 12.5 m (41 ft).
Its maximum speed is 155 km/h (96 mph).
Typical crew: 2.

Figures are for the representative variant described above; marks differ. See how AircraftIQ sources figures.

History

First flying in 1947, the K-225 proved the viability of Kaman's synchropter concept and led directly to the HH-43 Huskie. In 1951 a K-225 became the first helicopter powered by a turbine engine, a landmark in rotorcraft history.

Variants

The K-190 was a smaller prototype predecessor; the K-225 was itself a development aircraft that led to the military HTK-1 trainer and subsequent Kaman designs.

Where you'll see it

The K-225 was primarily an experimental and development aircraft operated by Kaman; it was evaluated by the US Navy and contributed to the evolution of the HH-43 Huskie, which saw wide US military service.

Related aircraft

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