Intermeshing
in the intermeshing layout,
the rotors are mounted
side by side, literally like the
beaters on an electric mixer.
The rotor shafts are tilted
outward to provide head
clearance, and the rotor
hubs also have dihedral or
“coning” for added head and
ground clearance. This layout
was first practically employed
on the WW ii Flettner Fl 282,
but it was more widely employed in
charlie Kaman’s series of designs,
most notably the outstanding
HH- 43 Huskie. The Huskie bloodline
continues today in Kaman’s compact
heavy lifter, the K-Max.
Intermeshing
helis, like the Huskie, use standard
collective and cyclic for altitude,
pitch, and roll control. For yaw
control, the Kaman designs use a
combination of differential fore-aft
cyclic and differential collective. This
makes these helis particularly agile
in tight quarters, which makes the
K-Max a nearly ideal heavy lifter.
Charlie Kaman was a brilliant engineer and inventor (in addition to helicopters, he invented the Ovation composite guitar). The intermeshing rotor layout gave Kaman’s HH- 43 Huskie record-setting payload and altitude capability, and his “servo flap” innovation greatly reduced stresses in the rotor head. Kaman’s early Ka-225 design was re-engined to become the world’s first turbine-powered helicopter, an innovation that allowed the helicopter to truly come into its own. (Photo by Anatoliy Lukich/ 123RF.com)
Summary
twin-rotor helicopters offer some interesting challenges to the builder, but these unusual projects never fail to
attract a crowd at the flying field. also, if they’re properly engineered, they can fly quite well. So, why not build
something different?
