‘Gyroplane’ is an official term describing an aircraft that gets lift from a freely turning rotary wing (rotor blades) and which derives its thrust from an engine-driven propeller. Historically, this type of aircraft has been known as the autogyro and the gyrocopter. The early names and 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 manoeuvrable. With the engine in the rear, the gyroplane has unobstructed visibility.
A gyroplane can fly more slowly than aeroplanes 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.
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 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 aeroplanes. The ability of gyroplanes to fly faster than helicopters and slower than aeroplanes 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 some gyroplanes take off and land vertically without having to hover. Helicopters at low altitude out of ground effect avoid hovering whenever possible. To fix surveillance on one spot, proper procedure for all rotorcraft is to circle in a slow orbit.
ASRA has written this article to assist fixed wing pilots to understand the behaviour of gyroplanes in the circuit and so enhance the ability of all aircraft to avoid potential traffic conflicts.
CASA formally defines a gyroplane as a power-driven, heavier-than-air aircraft supported in flight by the reaction of the air on one or more rotors which rotate freely on substantially vertical axes”.
In common use, the terms "gyroplane", "gyrocopter" and "gyro" refer to the same aircraft.
Gyros have very different flying and performance characteristics to fixed wing aircraft.
Gyros have high drag so they are relatively slow with typical cruise speeds of between 50 and 60kts.
Gyros cannot safely be flown fast but can be flown very slowly and can safely execute a vertical descent to wash off altitude quickly.
Gyros cannot stall because the rotational speed of their rotors and hence their lift, is not dependent on forward speed.
Gyro rotors are unpowered so a gyro is in constant autorotation.
Gyros are highly manoeuvrable and can execute a 60 degree angle of bank at any time.
Gyros have a poor glide ratio, at best in the vicinity of 4:1 in ideal conditions and nil wind.
Gyros are able to safely handle wind strengths exceeding 35kts.
Gyros are often described as short take-off and landing aircraft. This is a misnomer; take-off distance is dependent on ambient conditions (like any other aircraft), particularly headwind strength, and the amount of pre-rotation applied by the pilot before the gyro starts its roll. Pre-rotation is applied via an electric motor or power take-off from the engine. Pre-rotators are always disengaged during the gyro's take-off roll and not used in flight.
Depending on wind strength, gyros will come to a halt within 2 body lengths of their touch down point. At this stage the gyro's rotors are still rotating near flying speed so a gyro pilot will pause with the stick fully back to allow the rotor speed to decay before exiting the runway. This pause is typically less than 30 seconds.
Under CASA CAO 95.12 & 12.1, gyros are classified as an ultralight with a maximum flying altitude of 500ft AGL unless the pilot holds a specific endorsement.
Gyros may also legally operate at a minimum altitude of 300ft AGL and even lower with the permission of the landowner.
A standard gyro circuit is executed at 500ft AGL. Other than these differences, gyros operate under the same CASA regulations as other ultralights.
Gyros fly their circuit legs close to the active runway for 2 reasons. First, to compensate for their poor glide ratio in case of engine failure. Second, to improve the likelihood of faster aircraft sighting the gyro in the circuit and thus enhancing CASA's current "see and avoid collision avoidance policy".
Gyro pilots are trained to wherever possible use idle power on approach to ensure recency in simulated engine out approaches. Consequently, gyros typically execute a short final with a steep approach angle. This technique can lead to potential traffic conflict with faster fixed wing aircraft that fail to compensate for the slower gyro ahead of them on final and fail to take appropriate avoidance manoeuvres, often landing over the top of the gyro or having to execute a last minute go-around when they finally sight the gyro ahead and below them.
In addition, fixed wing pilots waiting to take-off occasionally fail to look up as well as out and force a landing gyro to take last minute evasive action to avoid a possible collision due to a runway incursion.