Mobile Hobbies: R/C Planes
Flight has always captivated the imagination, and while it isn’t practical for most people to have a full-size airplane at their beck and call, there is a way to enjoy the fun of flight for relatively little money and storage space. R/C (radio control) airplanes are small replicas of actual airplanes, and for those who dream of piloting their own aircraft, R/C planes provide pilots with all the flexibility and performance of full-sized airplane design.
The choices available for R/C enthusiasts are almost endless, and determining a good “first plane” can be a daunting task. For beginners, a good first plane should be durable, stable, and operate at a slower speed. For those who are intimidated by the idea of building a plane from scratch or in a kit, there are ready-to-fly planes (or RTF for short) that require no assembly. Make sure that the plane selected is easy to find spare parts for, as mistakes do happen while pilots are getting adjusted to the controls.
The amount of money needed for a plane will vary according to the model and manufacturer, as well as the power it runs on, but it’s sensible to expect to spend about $200-350 for a beginner bundle. Beginner planes, called trainers, will cruise at 25-30 mph (as fast as a car!), but more advanced planes can hit speeds of 200 mph. When flying an R/C plane, the plane will travel as far as the radio signal allows – generally up to a mile away. However, since it’s important to see the plane to determine what it is doing, most pilots choose to keep their planes much closer.
Planes will have a different number of controls depending on the make and style of the aircraft. A controllable element on the plane is called a “channel”, and the number of channels on an aircraft can range from one to six or more. The four most common channels on a plane are the throttle, rudder, elevator, and ailerons (the wing flaps on airplane wings that make a plane roll in the air). In addition to these controls, it’s important to learn about the same things that commercial pilots study in order to get the most enjoyment out of your new plane.
To fly, a plane’s wing has to develop “lift”, or the force of the air passing it, that is greater than the weight of the plane. This is what makes the plane fly, and the science of designing a plane to get the greatest lift is called “aerodynamics”. The placement of wings on an airplane is a part of the plane’s aerodynamics. High-wing models, or planes with wings on the top of the cockpit, are more stable since model's weight is suspended under the wings, and it tends to be self-righting. Low-wing models, where the wings are on the middle or bottom of the plane, have the weight on or above the wing, which makes the plane less stable, but much more maneuverable for tricks! Beginners should consider starting out with a high-wing model until they’re more comfortable with the controls.
But the wings themselves have special designs to be considered as well! If an airplane’s wing was to be cut, separating the top and bottom, the cross-section that would be visible is called the “airfoil”. A Flat-Bottom Airfoil, where the wing is flat on the bottom, will create, at low speeds, the most lift, and helps the plane right itself when it tilts in the air. A Symmetrical Airfoil design means that the wing’s bottom and top halves have the same shape, which means the same amount of lift regardless of whether the plane is upside-down or right side up. Advanced pilots favor this airfoil design, because (like low-wing models) it allows them to perform more tricks.
The surface of the wing is called “wing area”, and is a measure of the space available to create lift. There’s another measurement called “wing loading” that measures the weight that a certain section of wing has to lift. It’s measured in ounces per square foot usually, but the lighter the wing loading, the easier a plane is to control. Wing thickness will determine how much resistance – also called “drag” – the air can put on a plane. Thick wings, and by extension, lots of drag, mean that the plane will stall more gently and operate at slower speeds – this is usually what beginners look for in their plane wings. Thinner wings mean less drag, more speed, and sudden stalls, which can be a fantastic thing for racing and aerobatic (performed in the air) maneuvers.
You may notice that wings attach to the plane at an upward angle. This angle is called “dihedral”, and it increases the stability of a plane. However, dihedral decreases the ability of the plane to perform tricks, so it’s important to consider which quality is most important for your plane to have.
When it comes time to land, beginners will want to look for a plane with “tricycle gear” – this landing gear includes two main wing gears and a nose wheel. Landing gear makes landings and take offs much easier, and much safer for the plane!
Kits vs. Prebuilt Planes
Planes that come in kits will require some assembly, and while there are people who enjoy assembling them, many don’t like the complication of the small parts or the time that’s required of some of the more elaborate models. Fortunately, there are “prebuilt” planes that require very little assembly, and can be made ready to fly in under a day without having to pick up additional construction skills. Almost ready-to-fly planes, or ARFs, are planes that will need about 16 to 20 hours of work. RTF planes, as mentioned before, are ready to fly in under an hour after opening the box.
Choosing Your Plane’s Size
Model planes come in a variety of sizes, but the “size” of a plane isn’t what you might think. The “size” is actually the size of the engine required to fly the plane. A size 20 plane will need an engine that measures .20 to .36 cubic inches. Most trainers are size 40 (.40 - .53 for the engine), and are stable enough to beat back breezes without being ridiculously expensive.
There are two basic kinds of plane engines – electric and glow engines. Electric engines use batteries to turn the propeller. Glow engines are real engines, which run off a special fuel called “glow fuel”, and make a noise that imitates what a real plane sounds like. Glow engines come in either 2-stroke or 4-stroke varieties; a 2-stroke means that the engine fires with every revolution of the piston, and a 4-stroke means that the piston fires only once per two revolutions. Most beginners tend to opt for a 2-stroke engine since they’re easier to maintain and deliver the most power for your money.
Model R/C planes are controlled by radio, and most plane systems come with a radio controller and spare battery. For first-time pilots, it is wise to use radios that are “trainer” or “buddy” box enabled. What this means is that by connecting the main controller to a instructor’s or a friend’s box with a cable, the instructor or friend can take over if the pilot starts to have trouble with the plane. Most trainer planes do require four channels of control, but not all radio remotes offer this capability, so check to make sure the transmitter will work for your plane before you buy it!
Tools and Equipment
Both prebuilt and kit R/C planes will require some assembly, and for that, you’ll need some basic tools. A general “building kit” should include screwdrivers, pliers, a hobby knife, masking tape, sandpaper, and T-pins (pins with a special “T-shaped” head). You might also need a drill, but the instructions that come with your plane kit should help you determine what tools you’ll need. Special hobby glue is used to assemble R/C planes, and will usually either be a cyanoacrylate glue or modeling epoxy. Cyanoacrylate glue is specially designed to work with wood, and to fill in gaps between plane parts. Modeling epoxy, a sort of clay-glue, is ideal for super-strong bonds, but takes longer to mix and set.
When you go to fly your plane, you’ll need some basic “flight line equipment” to help get the plane off the ground and to have in case of emergency. A basic take-along kit should include engine fuel (if you need it; if not, an extra battery or two), a fuel pump (or charger), engine starting equipment, spare glow plugs and propellers, a wrench, and a battery charger.
A packaged R/C plane will fly out of the box, but that doesn’t mean it won’t need a little extra help. The accessory parts required are inexpensive, and will largely depend on the size and type of engine you decide to install on your R/C plane. Required accessories will be things like covering for the plane’s structure, pushrods, control horns to hold the radio wiring, hinges, foam rubber, wheel collars and wing seating tape, wheels, engine mounts, an engine muffler or glow-plug, fuel tank, tubing and filters, and the ever-fashionable spinner for the “nose” of the airplane.
While there is a learning curve, there’s no denying the fact that R/C flight is an engaging and thrilling hobby, and is well worth investigating. For more information on the basics of R/C flight, or for resources to guide you on your way to becoming an R/C enthusiast, see the following links.
- What is Aeronautics?
- Flights of Inspiration: The Beginning of Aeronautics
- What is Free Flight?
- Why Start with an Electric R/C Airplane?
- Learn to Fly
- Academy of Model Aeronautics
- International Miniature Aircraft Association
- First Flight Tips
- New Pilot Frequently Asked Questions
- R/C Pilot and Field Locator
- Model Aircraft Engine Types
- Installing and Using a Flight Simulator
- R/C Terms and Definitions
- Types of R/C Planes
- Getting Started for R/C Beginners (PDF)
- First Timer’s Crash Repair
- Using the Rudder (PDF)
- How to Build an R/C Plane
- Introduction to R/C Plane Aerial Photography
- Remote Control Aerial Photography Association
- 20 Things Every Pilot Needs to Know
- National Society of Radio Controlled Aerobatics
- Hobby Lobby: R/C Superstore
- FAA Regulations on Model Aviation
- How to Calculate Wing Loading and Center of Gravity
- Aircraft Trimming Chart for Aerobatic Flight
- Advanced Aerobatics