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It's a good idea to run such a check at your local flying field. Get a club member or a local flier to
coach you through this process the first time around. Remember to obtain the frequency-control pin
for your channel number before you turn on your transmitter!

Since fueled engine vibration and electrical noise generated by electric motors can have an effect
on radio range, run the same transmitter-antenna-collapsed range check while running your fueled
engine or electric motor. If everything is okay, you should be able to obtain the same range
regardless of whether the engine/motor is running or not.

On most four-channel RC transmitters with dual control-stick assemblies, there is a hook and eye
located in roughly the center of the front panel. This bracket accepts a neck strap that many RC
manufacturers supply with their systems. You put the strap around your neck and attach it to the
hook and eye on the transmitter case. The strap helps support the case, leaving your fingers free
to grip or operate both control-stick assemblies.

Complete transmitter support trays are also available. Their use is quite common with the RC pilots
throughout Europe. The tray is supported by a neck strap, then the RC transmitter is placed into
the tray. Longer-length control sticks are usually substituted. The pilot can grip them, making it feel
more like flying a full-scale aircraft. I encourage you, as a new flier, to keep it simple and resort to
these support devices later, as you gain experience.

I almost forgot to mention that most RC transmitters provide certain adjustment for control-stick
length and spring tension. You can read about how to do this in your operating manual. It is strictly
a matter of preference; I rarely change a factory control-stick setting on any of my transmitters.

There are several items you should be aware of as you begin your flight training. They will be the
subject of articles in the near future, as you absorb all of the details of this wonderful hobby.

One such item is a "trainer cable." Many RC transmitters have trainer jacks or connectors and
trainer-operated switches. You can purchase the cable as an accessory item from your RC-system
manufacturer. You must have the same brand of RC system, and it is helpful, though not
imperative, that you have the same model of RC transmitter.

The idea is to plug this 6- to 10-foot cable between the two transmitters. Only one transmitter will
actually send the signals or control commands to the aircraft. Your instructor holds one transmitter
and you hold the other. You will be in control of your aircraft, but if you get into a situation that
might prompt a crash, the instructor holds onto a long-handled switch and instantly takes over
control of the model. This is considered a better technique than having the instructor grab the
transmitter from you each time you get into trouble.

We have recently seen several self-stabilizing devices come onto the hobby market. The one that
comes to mind is the FMA Direct Co-Pilot, which I reviewed in the August 2002 Model Aviation
(pages 77-79). This device uses an infrared sensor, located on the bottom of the fuselage, to
sense and maintain level flight.

Let's say you make a turn and the aircraft starts to spiral and descend. Just take your fingers off
the control sticks, and the Co-Pilot will almost instantly return your model to level flight. This is
where the term "self-stabilizing" comes from.

Simulators are an extension of video games. They operate from a personal computer (PC) and use
a transmitter case and control sticks instead of the traditional mouse. You view the aircraft's flight
on the PC monitor and input controls via the transmitter box. These simulators have become quite
refined in recent years and offer considerable realism, making it easier to learn some of the basic
control maneuvers. The use of simulators will be the subject of a separate Model Aviation article in
the near future.

After all of this, you are ready to go out to the flying field and make your first flight. Well, almost
ready. We haven't discussed a specific first-time model. It is important to learn how to assemble it
(in the case of an Almost Ready-to-Fly, or ARF, type of model) and install the necessary RC
equipment, and then you can head out to the field for that first flight.

Next month I'll introduce you to electric-powered flight. It's my specialty, and I have used it
exclusively for many years. I've had considerable success training new RC pilots using this form of
power.

My intention in succeeding articles in this series is to select an electric-powered ARF, assemble it,
show how to operate it, then get you out for that first flight. After that I have a simple-to-construct,
original-design electric-powered sailplane to include. The idea will be to teach you "scratch
building" from magazine plans in its simplest form. All of the radio and electric power equipment
from your ARF will be transferred to the scratch-built model. You will also receive the all-important
flying instructions.

I recognize that not everyone in our hobby likes or wants electric power, so guest authors/experts
will write articles for this series to include such topics as assembling and flying glow-fueled ARFs
and basic building techniques and covering skills that everyone needs to know, regardless of what
power source you choose. We hope to get into model kit building as well.

Other types of models will be explored that do not employ RC, yet can be equally enjoyable to fly
(such as Control Line, Free Flight, rubber power, and Hand-Launched Gliders). That's what this
series is all about.
Please write in with your questions and suggestions to "From the Ground Up" in care of Bob Hunt,
Box 68, Stockertown PA 18083; E-mail: bobhunt@mapisp.com. That is most important to us. MA




			by Bob Aberle
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If you were dealing with a real model with a glow-fueled engine, at this point it would be appropriate to take it outside and run up the engine a few times. This would allow you to fine-tune the carburetor settings for the various throttle control stick and trim-lever positions. A guest author will write an article about fueled engine operation and the necessary support equipment (fuel type, fuel pump, starter battery, starter motor, propeller size, tank size, fuel lines, muffler, etc.) within the next few months. How much control throw or control excursion do you need for your first few flights? Model-aircraft manufacturers and model designers who publish plans in magazines usually provide guidelines for your initial flights. They may suggest one-inch rudder throw or travel on either side of the neutral position and half-inch elevator control on either side of neutral. If you don't get a recommendation, ask a friend who has more experience than you do or use the one-inch rudder and half-inch elevator for starters. It is probably better to have a little more than less control for that first flight. Once you get past that point, your instructor (hopefully you will have one!) will correct the control throws as necessary to make life easier for you as you learn to fly and solo. Making adjustments to increase or decrease control throws (control-surface movements) is generally handled by the selection of the hole position on the servo output arm and the control horn on the control surface. Moving the clevis attach point from the outside control-horn holes to the inside will cause increased throw. The same can be done (if more convenient) at the servo output arm. Moving from the outside hole closer in to the servo-output-arm hub will prompt a decrease in control throw. Never forget to make safety checks on your model. Do this before your first flight and on a regular basis thereafter. One of the most common problems is failing to properly attach the control-surface hinges. Hinge choices and their installation will be the subject of a future article. For now, no matter what type of hinge you use, physically pull on the control surface to make sure it is secured properly. Throughout the years, I can't tell you how many rudders or elevators I've pulled off of beginners' models before a first flight. You can have the best radio system and the best model in the world, but if a rudder or elevator falls off in flight you will have no model at all! In the same regard, make sure that all of your control-rod clevises, or whatever connectors you employ, are locked in place. Small keepers can be purchased to slip over the clevis so it can't separate. Other types of "keepers" prevent a Z-bend wire end from dropping off of a servo output arm. Also make sure you have that single screw in place holding the output arm to the servo hub. I've seen many output arms fall off in flight, only to result in major crashes. The radio and aircraft worked fine, but those pilots were beaten by a single missing screw (known as single-point failure). Most trainer-type models' wings are held to the fuselage with a few rubber bands. You shouldn't be too casual with what looks like a simple task; don't use a couple of leftover rubber bands. Most average to larger models should use the standard No. 64 rubber bands. The smaller models, such as park flyers, can use lighter-weight No. 33 size. You can find these rubber bands in quantity (bags or boxes) at the larger stationery stores (such as Staples and Office Max). Each model should employ approximately six rubber bands to hold down a wing. Use a cross pattern, such as front left dowel to right rear dowel (three and three). Although seemingly wasteful, use new rubber bands each time you go to the flying field; it's cheap insurance. Every RC receiver will have an antenna wire, which is usually roughly 40 inches long, exiting its case. On larger models you will have plenty of room to "hang" or stretch out this length of wire. On the smaller models you may end up with a considerable excess length that has to trail off the rear of the model. Don't cut any of this antenna wire off! Your receiver is tuned for that specific length. Making the antenna shorter can have a serious effect on your RC performance. Most important, the range of radio operation might be reduced. As you get into the hobby, you will learn that special shortened antenna rods can be substituted for the full length of wire. A primary source for these antennas is Eclectic Electric Necessities, or E-Cubed R/C (www.ecubedrc.com). Several models are available, down to as short as 11/2 inches in length. Radio reception is said to only be reduced by 15%. However, you will be required to cut off the existing antenna close to the receiver case, then solder the wire from the new rod to the remaining wire stub. For now I'd prefer that you stick with the supplied, full-length antenna. Antenna routing, or locating in the fuselage then out to the tail, is most important. If you get too close to such noise generators as a servo (the motor inside) or an ESC, you might see interference in the form of jittery controls or reduced radio range. The best idea is to get the antenna wire outside the fuselage as soon as possible, then route the long wire up to the top of the fixed vertical fin or out to the tip of the stabilizer. I generally drill two holes in the stabilizer tip or top of the vertical fin, and pass the antenna wire in one hole and out the other. I don't like to place any real tension on the antenna wire because it might eventually break. Nor do I favor attaching the antenna wire to any moving surface, such as the elevator or rudder; the constant flexing motion could eventually break the wire. With every new airplane and new radio-system installation, you must run a prescribed range check to make sure you have adequate control when the aircraft gets hundreds of feet away from you in the air. The best way to do that is to collapse the transmitter antenna as much as it will go. If it retracts all the way into the case, leave a few inches sticking up above the top of the case. By doing this, you will greatly reduce your transmitter's transmitting power, which will allow a simulated range check, but at a much shorter distance. Turn on the transmitter then the receiver. Operate all of the control functions. Have a friend hold the aircraft and walk away from you. You will be holding the transmitter and moving, say, the rudder control stick hard every few seconds. At the aircraft end you should see the rudder move positively to your exact commands. A point will be reached where the control surface will start to get nervous or jittery. A little beyond that point the radio may even stop working (the control surface locks or simply doesn't move). The exact point at which that happens can vary between 50 and 100 feet. The exact distance can be determined from your RC-system operation manual or by contacting the manufacturer directly. If you only get 10 feet or so, you have a problem. It might be in the radio itself, the batteries might not be charged, or the antenna-wire routing might be too close to a servo. No matter what the problem, it must be resolved before you attempt a first flight.

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