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FLIGHTTEST
These are the major assembled components of the 3D Frenzy as it comes out of the box. Note clutch, fuel tank and engine mount are already installed. All pushrods are assembled to the proper length, and even the engine mounting screws are in place. This is certainly more of an ARF than a kit.
grips. The swashplate can be configured for either 120- or 140-degree CCPM control, and push-pull linkages are used on all cyclic servos. The engine mounting block is made from CNC-machined aluminum, and the forward mounted engine design allows easy access to the glow plug. Other features include a large front-mounted radio compartment, a vibration-isolated fuel tank that is easily removed for maintenance, a low-maintenance, belt-driven tail rotor and a beautiful, prepainted white fiberglass canopy with decals. Although flybarless helicopters offer many distinct control advantages, they lose much of the inherent stability of the flybar. In fact, without the recent advancements in electronic stabilization systems, it would be impossible to fully benefit from flybarless control. The advanced features of the SK-720 allows it to replace the tail gyro,
GEAR USED Radio: JR 12X transmitter (jrradios.com), Hitec HS-7940TH servos (hitecrcd.com), Duralite A123 2300mAh 2S1P LiPo (duraliteflightsystems.com), Skookum Robotics SK-720 w/ 2 JR satellite receivers (skookumrobotics.com) Engine: YS 56 SR (ysengines. net) and MP5-50 Muscle Pipe (curtisyoungblood.com) and Perfect Regulators remote fail-safe switch Rotor blades: Edge 603mm Premium CF Flybarless and Edge 95mm tail rotor (amainhobbies.com) Fuel: Byron Rotor Rage Master’s Blend 30% (byronfuels.com)
In the Air Initial flight tests were flown using novice settings to evaluate the stability of the Frenzy. It was obvious from the first flight that this is a winning combination of helicopter and control system. Control was precise and predicable, even on a windy day. Small changes to the SK-720, combined with increased head speeds, brought out the full 3D potential of the Frenzy. GENERAL FLIGHT PERFORMANCE Stability: This is where the combination of Frenzy and SK-720 really shine. The easy to understand and use SK-720 allowed the taming of every flight parameter directly resulting in increased stability in all three axes. A lower rotor speed of about 1500rpm and push-pull servo control gave the Frenzy a smooth and positive feel to the controls, even on windy days. Forward Flight: Leaning out the YS 56 SR increased the rotor speed to 1800rpm and, combined with the specially designed Edge flybarless rotor blades, the Frenzy took on a whole new character. It moved when and where I wanted, but yet stayed “locked in” without a control input, making forward flight very smooth and predictable. Many helicopters have a tendency to pitch up in fast forward flight, but not this one. I took my laptop to the flying field with me, and changes to the SK720 were quick and easy to dial in the Frenzy just the way I like it.
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PITCH CURVES Normal
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Aerobatics: Although I have been using the name Frenzy throughout this article, the full name is the 3D Frenzy, which gives you a clue as to what this helicopter is all about. Cranking up the SK-720 parameters to the 3D mode and leaning on the YS 56 SR with Byron’s Rotor Rage Master’s Blend 30% Heli Fuel brought the 3D out of the Frenzy. Forget about tame and gentle maneuvering. Slamming the sticks from end to end brought out the power and precise feel of the Hitec HS-7940TH servos and allowed me to beat the Frenzy like a rented mule. My flying style is smooth and precise, but the Frenzy/SK-720 combination, together with a zero-slop tail rotor, brought out the wild side in me to try more aggressive maneuvers “up close and personal”—and I liked it! I think this combination of helicopter and control system is going to take me to a new level in my flying capabilities, and you will be hearing more about it in my “Rotor Speed” column in this magazine.
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