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| Flying Light Helicopters |
By Bill Orth, CFII, Chief Pilot RotorWay International
Somewhere along everyone’s aviation lifetime we have seen a small helicopter fly overhead. Some may have wondered what it would be like to fly one of these contraptions. A very few will actually go the next step and pursue that elusive dream. Hopefully, this article will enlighten you on some of the mechanics of the helicopter flight. Okay, before our first flight, let’s take a seat in our helo and review how the controls work.
Pedals
These look and feel just like ones in an airplane, except there is no toe-pushing to stop the aircraft on the ground. All the pedals do is change the pitch in the tail rotor. You push right pedal in a hover and the helo yaws to the right…push left pedal in and the helo yaws left. Just remember, some helicopters’ main rotors turn clockwise (like the RotorWay) and some turn counter-clockwise (like the Robinson). Basically, the tail rotor counteracts the torque imposed on the airframe by the main rotor blades being rotated by the power of the engine. One small difference in forward flight is that we don’t use the pedals to coordinate a turn. All we use is the cyclic control. The pedals are used to keep the aircraft in trim during cruise flight.
Collective & Throttle
This control is a lever with a throttle grip on the end, and is located on the left side of the pilot. As you raise this lever from the full down position it “collectively” increases the pitch in the main rotor blades. Raise the collective lever in a hover and the helicopter goes up… lower it and the ship goes down. The throttle is just like one on a motorcycle or outboard motor, except for one very important thing — it rotates backwards!!! The typical high-time motorcycle rider or small outboard fishing enthusiast usually has a bit of trouble with the throttle. Roll the throttle away from you (as you look down on it) to add power and towards you to reduce power. Just remember to forget bikes and boats when you’re in the helicopter and you’ll do fine.
Cyclic
This control stick is located between the pilot’s legs just like in an airplane. The main purpose of this control is to change the position of the helicopter in a hover or forward flight. When the main rotor disc is tilted, the horizontal component of lift moves the helicopter in the direction of tilt. Think of the main rotor blades as a big fan on top of the helicopter. If we tilt the big fan a little bit forward with the cyclic stick the fan pulls us forward…if we want to go rearwards we tilt the big fan a little bit backwards by moving the cyclic stick backwards.
Now that we have a grasp of how everything works, let’s take our first introductory flight in our light helicopter. We’ll start out from about a two to three foot hover. Okay…you have the controls!!! The first thing that usually happens is you start to turn in the direction that the torque is rotating the helicopter. Steady…just add a little pedal to stop the rotation. Sounds simple enough…oops…now that you added some pedal the helicopter is descending. What’s going on? Well, by adding a bit of pedal to counteract the torque you took power from the engine, which reduced the main rotor rpm just enough to make the helicopter settle a bit. You should have added a bit of throttle too. Now wait a minute…the helicopter is also drifting off to one side…and you didn’t even move the cyclic!!! Well, now that you added some pedal to stop the turn, you added tail rotor thrust, which pushes the helicopter sideways a bit more. You needed to compensate with a bit of opposite cyclic.
Wow…this is getting complicated. Not really…hovering is kind of like standing on a beach ball while rubbing your tummy and patting your head…how hard can that be? Realistically, it just takes a few hours of dual with a good CFI to get the hang of everything. You’ll be hovering this hands (and feet) full of machine sooner than you think.
Once you master the art of hovering, we can focus on the other realms of helicopter flight. For example, the Maximum Performance Take-Off. Helicopters can take-off and land in what we call “confined areas.” To take-off out of a confined area — say your back yard, which may have a lot of trees or nearby buildings — we start from the ground or a low hover. We locate the helicopter so it’s as far away as possible from the obstacle we want to clear. If there is any wind, we want to be facing into it. We roll on full power and slowly raise collective to start the accent. Now with full power applied we adjust rpm with the collective. We don’t want to just go straight up, so we add a little bit of forward cyclic to help us fly into the wind. Once we have cleared the obstacle we push forward on the cyclic and go for airspeed. Once we have normal climb airspeed, we make a normal departure from the area.
Now most people ask the question “What if your engine quits?” Well, we autorotate. This maneuver allows the helicopter to glide somewhat like an airplane, but with a much steeper approach angle. We store inertia in the rotor blades by maintaining a specific rpm during the glide. This is accomplished by lowering the collective at the first sign of an engine failure. This allows the blades to go from producing lift downwards to allowing air to pass up through the blades, thus maintaining rpm…kind of like windmilling the prop on an airplane but a much higher rpm. This stored rpm allows us to descend to near the surface, enter a flair to reduce our forward airspeed and vertical decent, and safely hover to the ground without an engine. These are real fun to practice once you get the hang of them. It allows the helicopter to make an emergency landing in a much smaller area than an airplane, which needs a runway or large field.
Hopefully this has sparked you interest in helicopters enough to make that next step in your flying career, preferably in your own personal helicopter. You are now well on your way to that Rotorcraft rating and that fishing hole only accessible by…you guessed it…a helicopter!!!
Bill Orth is a CFII and the Chief Pilot for RotorWay International. His experience includes the R-22, R-44, Schweizer 300, Bell 206, AS350, and EC120 helicopters, as well as time in single engine airplanes. For more information on RotorWay helicopters, go to www.rotorway.com, or call 480-961-1001. RotorWay International is located in Chandler, AZ and is the world's oldest and largest manufacturer of kitbuilt helicopters.
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| The material in this publication is for advisory information only and should not be relied upon for navigation, maintenance or flight techniques. SW Regional Publications and the staff neither assume any responsibility for the accuracy of this publication's content nor any liability arising fom it |
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