Flying the SparrowHawk

A gyroplane looks like a cross between an airplane and a helicopter. First developed in the 1920s, the gyroplane is one of the oldest forms of aviation technology. However, gyroplanes are not very common in the general aviation world, perhaps because of a reputation for being difficult or dangerous to fly.

It’s an undeserved reputation, says Randy Coplen, president and CEO of Seattle-based GBA Gyroplanes of Seattle, a distributor for the Groen Brothers Aviation Co.’s SparrowHawk gyroplane kit.

“Between 1920 and 1960 the accident rate of gyroplanes as compared to other general aviation airplanes was about the same,” he says. “Then from about 1960 to 2000 the accident rate for gyroplanes substantially increased because of poorly built aircraft, bad designs and little or no flight training.  People began adding bigger engines in the early 1960s, which created high centerline thrust. This would give the aircraft a tendency to pitch over. They also would build gyroplanes from designs they found in ‘Popular Science’ or ‘Mechanix Illustrated’ and would attempt to fly the experimental gyroplanes even though they had never flown anything before. They’d put them together using parts from the hardware store and try to take off from their driveways and then there would be accidents. It gave gyroplanes in general a bad reputation. Gyroplanes like the SparrowHawk are inherently safe if designed well, built well and people are taught to fly them.”

Gyroplanes are usually less expensive to operate than helicopters or fixed wing aircraft, according to Coplen. Unlike fixed wing machines that require several hundred feet of horizontal space for landing if the engine loses power, a gyroplane lands safely in a distance of 50 feet or less, at the speed of a parachute.

SPORT PILOT ELIGIBLE?

The SparrowHawk can fall into the Experimental Light Sport Aircraft (E-LSA) category. With most E-LSAs, an aspiring pilot must build his or her own aircraft. However, Groen Brothers Aviation has authorization from the FAA to sell fully assembled SparrowHawks. The manufacturer ships the kits to its Arizona dealership, which does the assembly.

“But if the customer wants to build it, we offer builders’ assist in Seattle,” Coplen says. “It takes the average builder between 300 and 500 hours to build a SparrowHawk. Working with us they can cut that time substantially and still meet the 51% rule. We also will provide final inspection by our certified aviation mechanic and fly the first five hours of test flying to make sure all the bugs are worked out. David Overman works as the test pilot for that program.”

Overman is also a gyroplane instructor. He provides SparrowHawk buyers at least 20 hours of training as part of the builder assist purchase package. 

According to Overman, becoming a gyroplane pilot — much less a gyroplane instructor — is a Catch 22 situation because, most of the time, experimental aircraft cannot be used in commercial operations such as flight instruction.

“With the exceptions of the Air and Space 18A and the McCulloch J2, all other gyroplanes are experimental aircraft,” he explains. “In order to use an experimental aircraft in a commercial business you need a special exemption from the FAA. That exemption is what we are permitted to operate under in Seattle.” He credits the lobbying efforts of the Popular Rotorcraft Association for persuading the FAA to grant the exemption.

“When there were no gyroplane instructors, people trained themselves to fly,” he says. “Many bought simple kits and had their spouses or friends pull them behind the family car until they felt comfortable enough to put the engine on and really fly. The lucky ones survived, but many others did not.”

According to the Popular Rotorcraft Association, Overman is the only certificated gyroplane instructor in Washington State. He became interested in gyroplanes as a teenager after reading an article about them in “Popular Mechanics.” He also holds pilot certificates for helicopters and fixed wing aircraft, so he was in a perfect position to answer questions about the potential pitfalls of a 900-something-hour fixed wing pilot transitioning into a gyroplane.

FLYING THE GYROPLANE

We met at Auburn Municipal Airport (S50) south of Seattle. Overman warned me to dress warmly, since the doors were off the gyroplane we’d be flying. That’s one of the nice things about this aircraft, he noted, but while it’s great for warm climates, photo sessions, hunting and surveillance work, it’s not very conducive to flight training in Seattle in early spring. I was glad I had brought gloves and had dressed in layers.

My rotorcraft experience comes from my TV days. I remembered that you’re supposed to rest your control arm on your leg to avoid over-controlling, and that the collective is for controlling the rotor blade pitch and the cyclic is roughly the gyroplane equivalent of an airplane’s control stick.

Overman did the preflight, checking the rotor blades for dings and cracks. As he checked the fuel level, he mentioned that the gyroplane burns auto gas.

I noticed a piece of orange yarn taped to the middle of the outside of the windscreen. That’s the yaw string, he explained. It’s used to gauge the direction of the relative wind.

Inside the cockpit I recognized the rudder pedals and noted that there is not much panel real estate in the SparrowHawk. The flight instruments are displayed on a small glass screen set between the two seats. When you choose your instrument package you have the option of selecting an airspeed indicator that uses either knots or miles per hour. This one used mph.

The cockpit measures 44 inches wide, which is considerably wider than most fixed wing training aircraft I have been in with the exception of a Duchess. It provides a comfortable teaching and learning environment.

We climbed aboard, made sure everyone was clear of the rotor blades and prop, and started the engine. There were the obligatory oil and fuel pressure checks and Overman checked the brakes. We made a few radio calls, then taxied to the active runway. You use rudder pedals to steer on the ground. They require more pressure than a Cessna 172, but about the same amount as a Cirrus, which has a castering nose wheel.

You have to be very conscious of where the rotor blades are and what they are doing as you taxi. This is more difficult than it sounds because, at low rpm, the blades have a certain amount of flex and it is more difficult to see them than, say, the airfoil of a fixed wing aircraft. The fact that the rotor is controlled both by the cyclic and the collective can make for a very bad negative transfer moment should a student pilot try to steer on the ground with the cyclic, as some students try to steer with the yoke of a fixed-wing aircraft, as though it were the steering wheel on a car. There is a chance of hitting the ground with the rotor blades.

Since Auburn is an uncontrolled airport, we pulled up to the hold short line and cleared the area visually for traffic. Overman made a radio call to advise area traffic that there would be a short delay on the end of the runway. The delay, which is less than a minute, is for pre-rotation of the rotor system.

We rolled into position and lined up on the centerline of the runway. While holding the brakes, Overman advanced the throttle to 1,500 rpm then engaged the pre-rotator. A quick check to make sure that the gauges remained in the green, then he called out the rotor rpm in increments of 10 as it increased. The rotor disk is held full forward until reaching 100 rotor rpm, then neutralized. At 120 rotor rpm the cyclic is pulled back to allow incoming air to speed up the pre-rotation.

Overman released the brakes and we started the ground roll, simultaneously advancing the throttle to 1,700 rpm and watching the rotor rpm increase to 150-160 rpm. We released the pre-rotator and allowed forward airspeed to build up the rotor rpm to 200 rpm, at which point the blades became rigid in space through centrifugal force. They need to be rigid in order to achieve flying speed. Once the rotor blades reached 200 rpm, full throttle was applied.

“We’re looking for the engine to rev up to 5,200 rpm, then we will apply enough forward pressure on the cyclic to balance on the main wheels until we reach an airspeed of 60-65 mph,” Overman explained. “The aircraft will want to lift off at a lower airspeed and fly in ground effect, so you need to apply forward pressure on the cyclic to keep it on the runway until you reach 60 to 65 mph. Once that happens, the gyroplane can lift off. ”

We climbed out at 1,000 feet per minute. With the doors off and all that forward visibility, it was quite a view. 

Overman gave me a heading to steer and stayed with me on the controls, chiding me not to be so heavy on the rudder pedals. The SparrowHawk rudder is large and effective, he pointed out, “so a little pressure goes a long way.”

We headed over to a practice area at an altitude of approximately 3,000 feet msl. We were looking for cruise airspeed of 65 mph. Overman advised starting the level off procedure about 50 feet before reaching the desired altitude, and gradually reducing the throttle to maintain cruise flight.

“Cruise engine rpm is usually between 4,200 and 4,800 depending on gross weight, density altitude, etc.,” he said, adding that the SparrowHawk burns about five gallons of automotive fuel per hour in that configuration. This makes it considerably less expensive to operate than a helicopter.

We did some climbs, descents and steep turns. I appreciated the maneuverability of the aircraft, but steep turns in a machine with the doors off are something I would have to get used to. I made the common student mistake of over-controlling. Overman coached me to relax and concentrate on flying with more fingertip and less wrist action.

COMING IN FOR LANDING

For this part of the flight it was all Overman. Gyroplanes, he explained, are required to avoid the flow of fixed wing aircraft and, as Auburn Municipal is a busy place (at least that day), with lots of fixed wing training going on, I was more than happy to let him take over.

Helicopters and gyroplanes fly at a lower approach altitude and closer to the runway than fixed wing aircraft, for the obvious reason that they do not need any more altitude to glide if the engine quits, or more horizontal space in which to slow down for landing.

Overman positioned us so we were at 500 feet agl and a quarter of a mile from the runway. Downwind was flown at 65 mph. When the numbers were abeam, he reduced the throttle setting by 1,000 rpm, relaxed the pressure on the cyclic and lowered the nose slightly to maintain airspeed. After a quick look on final to make sure it was clear, and an announcement to let others know where we were, Overman initiated a 180° turn and lined up on the centerline of the runway on final. Ever the instructor, he talked through the procedure.

“We are descending about 500 to 750 feet per minute. Airspeed is directly related to our attitude: if our nose is up, our airspeed slows, and if the nose is low, our airspeed increases. We maintain 65 mph indicated to 50 feet agl and round out, or adjust the nose up slightly, so we change from a nose down attitude to a gear down attitude, but we are still descending. This change in attitude starts to bleed off our airspeed as we descend to about 5 feet agl. At 3 to 5 feet agl we pull back lightly on the cyclic and lightly touch the tail wheel and mains simultaneously. Our airspeed at this point is 10 to 20 mph.”

As the wheels touched down Overman pulled full back on the cyclic and the rotor, all 30 feet of it, acted like a drag chute. The result was very little ground roll, if any at all.

The moment after touchdown is critical, noted Overman, and another of those places where fixed-wing pilots attempting to enter the world of gyroplanes get themselves into trouble, because they are used to releasing pressure on the yoke after the aircraft has lost flying speed. “In a gyroplane, the rotor blades are still generating lift and still need to be managed properly,” he explained.

TRAINING CURVE

The Sport Pilot ticket requires at least 20 hours of training, comprising 15 hours of dual instruction and five hours of solo flight, before a student pilot is eligible for the check ride. Provided the student flies consistently and acquires the basic skills and practices them correctly, solo flight within the 15-hour mark is an attainable goal, Overman said. 

“Sport Pilot gyroplanes are usually smaller machines and most are one seaters,” he said. “They are easy and fun to fly, and one can become safe and proficient in the required 15 hours of instruction. It is the same training as a private certificate with the exception of Class B airspace training.”

The Sport Pilot knowledge test for the gyroplane is 40 questions and applies to both fixed wing and gyroplane. For someone seeking private pilot privileges in a gyroplane, there is another written test, 100 questions long, for the single engine land certificate. There are also commercial and a gyroplane instructor written exams and practical tests.

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