| What
is a Gyroplane?
"Gyroplane"
is an official term designated by the Federal Aviation Administration
(FAA) describing an aircraft that gets lift from a freely turning
rotary wing, or rotor blades, and which derives its thrust from
an engine-driven propeller. Historically, this type of aircraft
has been known as the autogiro and the gyrocopter. These early names
and their variants were filed as trademarks.
Gyroplanes
derive lift from freely turning rotor blades tilted back to catch
the air. The rushing air spins the rotor as the aircraft is thrust
forward by an engine-driven propeller. Early gyroplanes were powered
by engines in a tractor (pulling) configuration and were relatively
heavy. Modern gyroplanes use a pusher propeller and are light and
maneuverable. With the engine in the rear, the gyroplane has unobstructed
visibility.
Gyroplane
- Helicopter Comparison
The Gyroplane
-
Thrust is produced by an engine-driven propeller
-
The unpowered, freely turning rotor is tilted back as the gyroplane
moves forward
-
Oncoming airflow through the rotor causes it to spin, producing
lift. This is called autorotation.
-
Always operates in autorotation, thus:
-
Cannot stall like fixed wing aircraft
-
Flies safely at low altitudes and low speeds, but cannot hover
-
No need for heavy main rotor transmission nor a tail rotor
The
Helicopter
-
The powered rotor produces both lift and thrust, and is tilted
forward
- Can hover,
but a powered rotor requires:
- Adequate
forward speed and/or altitude to maintain flight in case of
power failure
- A heavy
main transmission
- Tail rotor
to counteract the torque imposed on the aircraft
A
Gyroplane can fly more slowly than airplanes and will not stall.
They can fly faster than helicopters but cannot hover. Since the
rotor blades on the gyroplane are powered only by the air (autorotation),
much like a windmill, there is no need for a tail rotor for anti-torque.
The gyroplane is a stable flying platform. This is not so with helicopters,
which pull the air down through engine-powered rotor blades making
it possible to hover, but also making the aircraft very complicated
and expensive to fly. Due to their inherent simplicity, gyroplanes
are easier to operate and less expensive to maintain than helicopters.
Design
Simplicity
The simplicity of a gyroplane's design translates directly into
safety, higher performance, higher mission readiness, lower maintenance,
and more economical operation for its operator.
Gyroplanes in flight are always in autorotation. If power fails
in a gyroplane the autorotation continues, and the aircraft settles
softly to the ground from any altitude. The procedure to land after
a power failure is nearly the same procedure as a normal landing,
which requires no landing roll. Thus the gyroplane is a safer aircraft
for low and slow flight, as compared with both helicopters and airplanes.
The ability of gyroplanes to fly faster than helicopters and slower
than airplanes makes it something of a hybrid, having the good qualities
of the other two types of aircraft with little of the bad.
The single attraction of helicopters over gyroplanes is their ability
to hover, which is necessary in some situations such as rescue or
in sling load work. In air surveillance and point-to-point flying,
not being able to hover is not a disadvantage because many gyroplanes,
such as the Groen Brothers Hawks, take off and land vertically without
having to hover. Helicopters at low altitude out of ground effect
avoid hovering whenever possible. It is too dangerous. To fix surveillance
on one spot, proper procedure for all rotorcraft is to circle in
a slow orbit.
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