Getting started guide

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Radio controlled flight is a fascinating hobby requiring the development of a number of skills beginning with the basics of flight control.

Once you have made the decision to learn to fly R/C, the next step is to visit your local flying club and see if you like what you see in terms of the facility and the members themselves. It's not essential to join a club and lots of people do teach themselves to fly, but it's a lot easier to learn from people with experience and it's more fun to share your hobby.

Deciding on a first plane

You need a dedicated trainer, preferably an electric especially if you are teaching yourself. At this point, you should not be concerned with scale looks but ease of control. It isn't long before a scale plane in the hands of a rank beginner will suffer damage. It is suggested to make a plane of the scale variety your second or third plane.

Two-channel planes which steer, climb and dive solely via rudder and throttle make good beginning aircraft and are good for learning how to overcome control reversal when the plane is facing you, but they have some distinct disadvantages. Though fun for younger pilots, the lack of pitch control makes a plane of this type extremely easy to lose should the wind come up during flight. Early HobbyZone aircraft are an example of these types of trainers; the brand's newer offerings are three- and four-channel.

A three-channel aircraft utilizing rudder, elevator and throttle will require a little more learning but is a better overall choice. These are the same control inputs as more advanced planes and can be flown in more wind once you have mastered them in calm conditions.

Most trainers are of a high-wing design, providing the stability to roll level when you let go of the sticks.

Some planes have the motor mounted in the rear in a "pusher" configuration so that it isn't the first thing to hit the ground in a crash. There is a performance penalty for this, but it's a great feature when you're learning to fly.

There's a good comparison of the most popular 'trainer' planes here: http://www.plawner.net/3/1st_plane/1welcome.html

For a small field, a three-channel "slow flyer" such as a GWS Slow Stick or ParkZone Slo-V is a good choice, but won't handle much wind. Flight speed is relatively docile, giving a beginning pilot more time to react to problems. Both the prop and motor are vulnerable in nose-first crashes.

A similar option (for small, sheltered fields) are the 'Ultra Micro' parkzone planes (J3 Cub and Champ). They are cheap and their light weight makes them very tough when crashed into grass, but they won't handle much wind.

For a larger field, the Multiplex Easy Star is very popular; it will handle some wind and rarely costs anything to repair after a crash. However it is quite large and heavy, and doesn't turn quickly so you need 3 or 4 football pitches to fly safely.

Models such as the Easy Star, while easy to fly, require the aid of an instructor for first flights to prevent them disappearing down-wind. Other examples of RTF trainers of this type include the Flyzone Switch, Flyzone Sky Fly Max and .

If you have an instructor and buddy box and have practiced on a simulator, a more advanced 4-channel trainer such as the E-flite Apprentice, Multiplex Twin Star (or Mentor) or the ST Models Discovery is a viable option, skipping the 3-channel stage. However, without a buddy-box your instructor is unlikely to be able to save this sort of model after every mistake, and without an instructor the model would have a very short life!

If you just want to see if you like R/C flying without spending much, or want a very easy introduction for someone who might be intimidated by a bigger plane, try the Silverlit X-Twins Airhogs AeroAce differential thrust toy. It's cheap, flies well and is pretty much indestructable, but can be difficult to fly in anything but dead calm conditions.

RTF, ARF or kit? What does this mean?

  • A ready-to-fly typically requires virtually no building. Generally, one attaches the wing, landing gear and perhaps the tail and you are done. Typical investment of time is under 2 hours and can be as little as five minutes. The Aerobird Challengeris a good example of an RTF plane. RTFs always include an installed radio system and may also include the battery and charger. The radio gear is rarely suitable for transferring to another plane and can have poor range compared to a discrete, off-the-shelf radio system.
  • ARF or ARTF (Almost Ready-To-Fly) are planes that require very little building, but do require the purchase and installation of the radio gear. This gives you the choice of radio gear and the freedom to move it to another plane in the event of a crash or graduation from your trainer. ARTF planes can be built by an experienced modeler in as little as two hours. If one is unfamiliar with the installation of radio equipment and linkages, build time is considerably longer.
  • A kit is a completely "knocked down" model consisting of unassembled components. These require a significant amount of building, more so than any other type of model save for a scratchbuilt plane built from plans. For some, building is as much or more fun than flying. An op-ed column by writer Bob Hunt in the December 2005 issue of Model Aviation magazine decries the popularity of ARFs and RTFs owing to the fact that these types of models "dilute" an important aspect of the hobby.

As stated, ARFs and kits always require you to buy and install the electronics. However, some makers (such as Mountain Models and GWS) and many of the resellers offer select packages that include the kit and the electronics, often at a discount. You still have to assemble and/or build, but all the guesswork is taken out of which electronics to buy. This makes it very easy for the first time builder to "get it right."

ARF vs. kit. How are they different?

  • All foam kits are more similar to ARFs than they are to wood kits and are generally labeled as such. They typically consist of large molded pieces that glue or friction-fit together. They typically take 3-10 hours to complete and most of that is installing the radio gear.
  • Some foam kits call for covering but many (the Graupner Tipsey, for example) do not.
  • When required, covering can often be done with tape which can be very easy for the new builder. As a first step up from an RTF, models of this type can be very good choices. It should be noted that tape adds considerable weight and should be added only if the manufacturer calls for its use.
  • Mixed foam and wood kits are likely to require some stick and sheet assembly, but typically much less work than an all-wood kit. The Mountain Models SmoothE is a good example. The fuselage is wood but the wing is foam, making it very easy for the first time builder to be successful.
  • Most all-wood kits consist of sticks and sheet parts that are diecut or laser-cut. These are first glued together per the plans and/or instructions to form the basic structure. This is then covered with heat-shrinkable, adhesive-backed polyester film. Build time ranges from 10-30 hours. As an example, Mountain Models wood kits are typically very complete and often include the motor, the hardware and the covering material. For those interested in constructing an all-wood kit for the first time, Mountain kits have an outstanding reputation for ease and completeness. This thread talks about their planes.
  • Wood ARFs are typically kits with major assemblies and subassemblies that are already built and covered. All that is required is final assembly. The Ascent is a good example. Typical build time is in the 3-10 hour range. Much less time than what is necessary to complete a kit is required, but modeling skills are still very important. See Carl Goldberg Chipmunk 400 for an article on just such an aircraft.

Which radio?

Most manufacturers now sell 2.4GHz radios, which do not conflict with each other. Some switch frequency many times every second, other pick two quiet frequencies when you switch them on - they all use digital algorithms to isolate their signal from other noise.

Older radios (72Mhz or 50MHz in North America, 35Mhz in the UK or 27MHz in both areas) are set to specific channels within their specific frequencies. Two radios on the same channel will conflict, preventing either from working reliably and causing a crash if one should power up a transmitter set to the same channel as a model in the air. If you're using one of these, it's essential to check which channel everyone else is using before you switch on. In an informal setting, asking aloud if anyone is using the same channel is acceptable; in a club setting, a clipboard listing individual frequencies is used. A club membership card or other marker is clipped to the board under the channel one wishes to use. If a card or other identifier is clipped to the channel, do not turn your transmitter on. Instead, locate the flyer on that channel and coordinate turns in the air with him or her. For this reason, 2.4GHz radios are recommended for new pilots, and as they are now often cheaper they have become the first choice of virtually all R/C pilots.

50MHz radios in the US may only be used by people holding an amateur radio license.

Check which accessories come with the system you are considering. Many inexpensive systems do not include a rechargable transmitter battery and charger, an important long term cost-saving measure. Except for systems sold in the United States, many even lack crystals. (Although transmitter and receiver crystals are designed to be easy to change if one wishes to switch frequencies, there remains the possibility of slightly off-tuning the system and creating interference to other models. It is for this reason that Federal Communications Commission regulations prohibit frequency switching via a simple crystal swap.)

If you are flying at a club, get the same make as everyone else and make sure it has a buddy box socket. (having the same make will also help with computer radios, as they can help you set it up).

Some of the cheapest radios opperate on 27MHz. These are generally found on inexpensive RTF and toy-grade models both air and surface, although most manufacturers are upgrading their 27MHz models to 2.4GHz operation. This is only suitable for the cheapest of planes as the band is also used by citizen's band two-way radios and interferance is always a possibility.

Most trainers will only require three channels, and you may not need four channels for quite a while, as many aileron planes don't require a rudder. Conversely, rudder-steered planes do not require ailerons.

It is often recommended to buy a 'computer' transmitter. You will most likely buy one within a couple of years so it's a good investment. However, there are lots of other things that you need to buy and a 'starter' radio can usually be sold on to another beginner. 'Computer' transmitters usually have at least 6 channels, but that's not the main reason for getting one. They have memory settings for multiple models; this feature greatly simplifies using the same transmitter when you have more than one model. The ability to mix servo inputs for planes such as deltas, flying wings, V-tails and "flaperon" aircraft is extremely important as well. High-end radios of this type use solid-state, digital controls instead of potentiometers and switches.

Radio systems generally consist of the following components:

  • Transmitter with crystal and batteries
  • Receiver tuned to the same channel as the transmitter
  • Servos that move the control surfaces or in the case of an engine-powered model, the throttle as well.
  • A receiver battery (this is often replaced by an electronic speed control or ESC for an electric model. This controls the speed of the drive motor and provides power for the receiver and servos. A separate receiver battery is always necessary for gliders and engine-powered models.)
  • A wall charger for both receiver and transmitter batteries.

Receiver plugs are pretty standard and most will accept any ESC and servo. There are a few exceptions, however. Battery plugs are not standard, but you can change them; make sure your batteries will fit your ESC and charger.

While nearly all 2.4Ghz gear is brand-specific, most older brands of transmitter will work with most brands of receiver, but crystals are brand-specific, i.e., you need a Futaba transmitter crystal in a Futaba transmitter, a Hitec receiver crystal in a Hitec receiver, etc. but the two will work together. In the United States, you are allowed to change the receiver crystal but not the transmitter crystal.

You will also need some of the following to complete and maintain the model:

  • Glue
  • Tape
  • Velcro straps for securing the battery
  • Rubber bands for planes requiring them to attach the wing
  • Spare propellers

How do I connect all these little boxes?

The servos and ESC plug into the receiver. The three-pin plugs are polarized and color-coded as follows:

  • Signal - White or orange
  • Positive - Red
  • Negative - Black

The ESC has additional connections:

  • Battery wires with a suitable plug for your battery either factory-installed or installed yourself
  • Motor wires with two plugs for brushed motors and three for brushless. The two are incompatible.

The battery needs to be disconnected from the ESC for charging and should not be left connected when not in use.

You'll have to experiment with which servo to connect to which channel because there is no standardization between brands. Make sure the propeller is not attached while you do this, because it could suddenly start while you are making adjustments. They have a lot of power and the prop is sharp enough to inflict serious personal and/or property damage.

Finally, for safety, always turn the transmitter on before you connect the battery to the ESC, and unplug the battery before switching off the transmitter. When the transmitter is off, the receiver could pick up some random signal and do anything, like start the motor or run the servos so far to one end that they jam and burn out.

Before you fly

If you do try to teach yourself to fly, it is highly advisable to:

  • Pick a suitable model and be prepared to repair it.
  • Have the model checked and test-flown by an experienced pilot. It's hard enough to learn to fly a well set-up plane and there are many simple mistakes that can make it much harder. RTF planes attempt to address this but building and set-up skills greatly improve the satisfaction and enjoyment available from the hobby.
  • Ensure that your flying field is large enough with no obstacles. This depends on your model but a couple of football fields is a good rule of thumb.
  • Pick a calm day - wind will make it harder to control and greatly increase the chance of the loss of a model. The AMA recommends writing your name and address on the model in case this does happen.
  • Ensure you aren't within a mile/1.6km or so of an existing flying club as their radios could well interfere with yours, causing you to lose control. Likewise, your radio could affect their models, which could be much larger and more dangerous.
  • Ensure your field is empty. Dogs will chase your plane and other people may consider your plane more dangerous than you do.

Flying the plane

When you're ready for your first flight you have two alternatives:

  • Launch into the wind and get plenty of height so you have lots of time to get use to it before you have to land.
  • Try some short test flights, just throwing it with the power off to check everything is OK before risking the extra speed and height of a proper flight. This works for smaller, lighter planes, especially if there is some long grass to soften any crash.

Once you get the plane in the air, get some altitude. You might feel that the higher the plane means a harder crash but in reality it means more time to correct any mistakes. Keep it upwind from you at all times to prevent a fly-away.

A common mistake is overcontrolling. Controlling the plane only needs fairly small movements of the sticks, although you may have to wait a second or two to see anything happen on a slow-flying trainer. In a turn, bring the sticks back to neutral and the plane should stay in its turn until you countersteer. Don't ride the controls in a turn. A plane which steers with ailerons will continue to roll over while a plane which steers with a rudder will enter a spiral dive.

To turn, apply some right stick until the plane is banked about 30 degrees from horizontal. Center the stick and watch - the plane will continue its turn and may drop the nose, easily compensated with a little bit of 'up' elevator. It might straighten out on its own, or it might need a little bit of opposite rudder. Once it levels out, it might try to climb and need a little bit of 'down' elevator to keep it level. The reason is simple: When the wing is banked in a turn, it loses lift. Once it straghtens out, lift is restored.

Avoid flying at constant full throttle. Doing so will dramatically shorten flight time and will make the plane "twitchy" to control. It will also give your airplane more of a tendency to climb. Reduce the throttle to the minimum where it will maintain height comfortably and think of this as "cruising speed."

A good way to practice for the inevitable dead battery or stalled engine is to see how the plane reacts when you cut the throttle completely. Do this with plenty of altitude because the nose may drop quickly and the controls will be far less responsive. Cut the power and see how shallow a dive you can maintain without stalling. Most trainers will glide fairly well but you might need a little throttle to maintain control.

When it's time to land, go a little way downwind, turn into the wind and begin reducing power. A bit of down elevator may be used as well as flaps if so equipped. When the plane is a few inches off the runway, level out and cut the power completely if it's not already off. A bit of up elevator added prior to touchdown will partially stall, or "flare" the aircraft prior to touchdown. With experience, learning how to flare the touchdown will result in smooth, accurate landings.

Control reversal

New pilots who have never operated a radio controlled model of any type will almost invariably steer the wrong way when the plane is coming towards you. You want the plane to go to your left, you steer left and the plane goes to its left (your right). With practice, this compensation becomes natural. At first, you may wish to picture yourself in the plane.

There are two other techniques to overcoming this. One is to twist your body so your shoulders and the transmitter antenna are pointing the way the plane is going. This may leave you looking over your shoulder at the plane. Now, your left and right will be oriented the same way around as the plane.

The other way is to remember that things are reversed. Good mnemonics are "steer the wrong way" or "prop up the low wing with the stick." Of course, conscious thought is always slower than reflex.

Stall

A stall is when a wing is flown at too much of an angle. The airflow breaks away from the top and it stops making lift. This happens when the plane is flying too slowly or gets into an orientation that does not allow for forward flight, such as an extreme nose-up attitude. Pulling more up elevator won't help because the wing is already pointing up too much. What is needed is more speed, so put the nose down and allow the speed to build up before pulling out of the dive. Learn to recognize the speed at which your plane stalls before attempting a landing. Some planes can stall in straight and level flight if airspeed is too low.

Simulators

A number of highly realistic and accurate computer simulators are available, some are even free. This is a very useful way to experience R/C flight, get a feel for what a plane is about to do and build critical muscle memory. As you progress beyond the basics into aerobatics you'll probably want to use one of the more realistic simulators. In fact, many competition R/C pilots practice this way. See RC flight simulator for more information.

Most simulators come complete with "dummy" transmitter. You can also use your own transmitter with a special cable which connects it to the Serial, Joystick or USB port via the buddy box socket. These cables are purchased separately and are specific to the make of transmitter (and sometimes to the simulator) Information is availabale at Hitec's website.

An excellent free alternative is Flying Model Simulator. Downloadable models of most common trainers are available for FMS. While you can use a keyboard or joystick for control in FMS, it is highly recommended to either purchase a two-stick USB joypad for around $20 or ideally, if you have a radio with a buddy box socket, a lead as described above.

If you find a simulator hard to start with, try flying in 'chase plane' mode. That way you don't have to worry about losing the plane in the distance, or knowing which way to steer when it's comming towards you. Remember that this is only a cheat to get you started; you will need to learn to fly from the ground before you try the real thing.

Links

The following articles address specific issues:

If you are totally new to R/C flying, these may be helpful.