The main goal of hovering an RC helicopter is to keep it in one spot with as little moving or drifting as possible. Ultimately, you'd like it to remain absolutely motionless, but in a non perfect world, that's nearly impossible as there are too many factors that will cause drift or motion. For the beginner pilot hovering an RC helicopter can prove to be excessively difficult and many people give up on the hobby because they can't master hovering. While it is possible and people do fly RC helicopters without being able to hover properly, it's not recommended. It's like learning to run before you can walk and you'll eventually run into a problem. Being able to hover teaches control and fine motor skills that you'll want to have to become a better overall pilot. Even top performers practice hovering to hone their skills. There are 4 main hovering positions, or 8 if you count inverted hovering, but I'm not going to get into that as it's a lot more complicated than learning basic, right side up hovering that we'll discuss in this 'how to' article....
Tail in hovering is where the tail is pointing towards you and the nose of your helicopter is away from you. Nose in is the opposite - where the nose of your helicopter is pointing towards you and the tail is pointing away from you. Right side in is where the nose is pointing to the right, the tail is pointing to the left and you're facing the right side of the helicopter. Left side is the opposite, where the nose is pointing to the left, the tail to the right and you're facing the left side of the helicopter.
Pre-flight Setup & Checklist
Before you can learn to hover your RC helicopter, you need to make sure your helicopter and radio is properly setup. If unsure, consult an experienced pilot or your local hobby store. Put your training gear on. If you don't have some, buy it. It costs $20 - $50 and if you're just starting out will save you hundreds in crash damages. The training gear also makes a good visual aid that help you see the pitching and rolling of your RC helicopter before you notice them in your helicopter. If you're flying a nitro helicopter, have lots of fuel available. If you're going electric, make sure your batteries are charged and have more than one available if possible. The more you can fly continually, the faster you'll improve your skills.
Make sure your gyro is set to heading hold mode. While some people recommend flying with a gyro in rate mode because you'll get a better feel for the helicopter, I don't recommend it for the simple reason that unless you plan on building scale ships, you'll probably never use rate mode, so there's no sense learning to fly with it. Also, make sure your radio and helicopter is set up for hovering and that it's not too sensitive. If it's too sensitive or quick to respond, you can try adding some expo to the cyclic to soften the sticks around their centres, or decrease the endpoints to decrease the amount of cyclic pitch and responsiveness of the helicopter. And finally, go through your preflght checks.
Getting a Feel for Your Helicopter
Before you learn to hover, you need to understand how your RC helicopter works. When you move the sticks, how does your helicopter react? If you input right cyclic, how quickly does your helicopter react? The goal is to learn how your helicopter moves and corresponds with the inputs you give. Once your RC helicopter and radio are setup, you'll need a practice area. You're going to want the surface you're practicing on to be as smooth as possible so you can slide around a bit. A gym floor, a large and smooth cement basement, a ice rink or a smooth asphalt make the best practice surfaces - the smoother the better. If you're trying to learn on a rough or uneven surface like grass or gravel, your RC helicopter can catch on it and tip over. The training gear will help you slide around without fear or tippage. Make sure you have at least a 10ft x 10ft (20ft x 20ft or larger recommended) area that is clear of any and all obstructions. The larger your helicopter is, the more space you'll need. If there's no marking to use as a reference point, use a marker or masking tape to create one. Put your helicopter into the middle of the space pointing into the wind (if outdoors) and stand 10 - 15ft behind it. Start to throttle up very slowly - you don't want it to lift off the ground, just get it light on the training gear so you can slide it around. If your main blades rotate clockwise and your helicopter has been built properly, there's a good chance that it will want to drift slightly to the left to counteract the tail rotor thrust pushing to the right. If your rotors spin counter clockwise, your helicopter should drift slightly to the right. Use the trims to compensate for the drifting until your RC helicopter stays fairly stationery. Once you've got the trims set, give a little right cyclic input and watch as the helicopter moves to the right. Then give left cyclic input to move it back to the reference point. Then do the same thing moving your helicopter forwards and backwards. The main goal here is to get a feel for how the helicopter responds to your stick inputs and how much input is necessary to get it to move. You'll find small stick inputs are all that is necessary. Once you're comfortable with side to side and forwards / backwards movement, bring the helicopter back to your reference point and move it diagonally in all 4 directions. This will be a lot harder then left/right forwards/backwards movement because you'll be inputting multiple cyclic commands simultaneously as well as controlling the tail. You'll want to practice this until you can make very precise movements and are comfortable moving your helicopter around. Remember to always fly your helicopter by watching its nose, never by looking at the tail boom.
Learning To Hover All right...on to the good stuff.
Once you've got a feel for how your helicopter moves and how to control it using your radio, it's time to get it off the ground. For this, you'll want to move from your smooth surface to something softer, preferable short grass. This will help to absorb any impact from hard landings and prevent damage. If you have a really small or micro RC helicopter, you can do this on the same hard surface you used earlier as there's not much weight to cause damage. Pick or mark a reference spot and place your helicopter there going through all the pre-flight checks mentioned earlier. Input collective until your helicopter is just a few inches off the ground and try to hold it there. Remember that very small inputs make a big difference, so be gentle on the controls. Pay attention to your helicopter and the balls on the training gear and try to anticipate any movement and try to compensate for it in advance. To become a masterful hoverer you need to be able to tell what's going to happen in terms of movement and react to it in advance to prevent it from happening. As you become more comfortable, start to bring it a little higher and higher until you get it up to 2 - 3ft and can hold it in one spot.
You can now hover an RC helicopter... everything else is downhill from here. Though you'll probably want to go through at least 3 - 5 batteries or tanks of fuel practicing stationary hovering before you start to move your helicopter around to make sure you'll be able to react in time in case of a mishap. As s side note, when practicing hovering, you'll usually want to hover above 2 - 3ft to avoid ground effect. Ground effect is when your RC helicopter is hovered close to the ground (under one rotor diameter) and the downwash of the rotor blades creates a high pressure bubble of air. This bubble of air applies an uneven upwards force which causes the helicopter to wobble or move sideways making stable flight difficult. It's a little like balancing a basketball on your finger (when it's not spinning). For those reasons, when practicing hovering, I prefer to hover at about 3 - 5ft. It's high enough to avoid the ground effect and low enough that I'm looking slightly down at the helicopter and can use the ground as a reference. The higher you get, the harder it is to perceive depth and keep the helicopter in one place - there's also no easily perceivable frame of reference against the sky as there is on the ground. However, with that being said, if you're just starting out you might want to hover a little higher in case you make a mistake so you have time to recover. Many people use the saying "practice 2 mistakes high" meaning that you have time to recover from at least two mistakes before your helicopter becomes acquainted with the ground, the hard way. Tip: Use a simulator for practicing and once you're comfortable on your computer try it on your RC helicopter. Once you're able to easily hover your RC helicopter tail in, it's time to start moving it around a little. Repeat the same left/right forwards/backwards and diagonal movements that you did in the previous section, but this time your helicopter will be 2-3ft in the air and when you get to your new position, hold it there for 15-20 seconds before moving on. Transitioning from flight to hovering will help to improve your skills and take you to the next step. Stationary side in and nose in hovering is significantly more difficult than the tail in hovering exercises mentioned in this article because cyclic commands are 90 or 180 degrees off depending on the position. For example, when nose in hovering, if you input a right cyclic command, your helicopter will move to the left and vice versa, so I'll save them for another time.
Now go out there and enjoy your Remote Control Helicopter, by far the best remote control toy money can buy.