FREQUENTLY ASKED QUESTIONS

If you are just starting out in R/C (radio controlled) flying, or just thinking of it, be sure to read at least the Introduction and the sections on Building/Buying, Learning to Fly and one of Gliders or Electrics. We have tried to address all questions a beginner may have; if your question isn't here, please speak to the head instructor or club executive and we’ll include it.
We suggest you also take the time to check out Fatlion's site on R/C Soaring for Beginners. Remember, no amount of FAQ reading can substitute for an instructor!

MAIN MENU

1)  Getting Started; Radios, Buying & Building Kits, ARFs and Scratchbuilding
2)  Learning to Fly; Instructors, Pre-flight checks
3)  Gliders; Launching, Staying Up, Recommendations and Costs
4)  Electrics; Advantages, Equipment, Motor Specs., Recommendations
5)  Elementary Aerodynamics; Speed, Turning, Stalls
6)  Suppliers; club recommended, both local and mail order

1) Getting Started

Radios - Which Radio?

Since a trainer needs only 2 or 3 channels, should I get one of the cheap radio systems?

For starting out with a trainer, we recommend single stick two channel setup. You can get one for about $99 Cdn from the various Canadian mail order houses. This radio/trainer combination should last you for your first full season of flying (and well into your second ). A 3 channel version has just been introduced that is ideal for the budding electric flyer. Be sure to consult the MATS radio frequency chart, available from any member of the executive (and on the web page), before buying any radio equipment. This will reduce the chance of frequency conflicts and will give you more ‘stick’ time at the field.
If you have full intention of progressing into higher performance aircraft, don't bother with the cheap 2 or 3 channel sets, get a 4-ch system. It will come with NiCad rechargeable batteries and (usually) 3 servos; this is the most popular and most cost-effective kind of system. You can put the main pitch control (elevator) and the main turning control (in this case the rudder) on one stick, which is how most people (and thus most instructors) fly. Cheaper setups like the described earlier are delivered configured for non-rechargeable cells, they can however be adapted for Ni Cads with an upgrade kit from the manufacturer.

What is a "1991" system?

Strongly recommended! A "1991" system is so named because in 1991 the radio control frequency regulations changed, which effectively made the "old-style" radios unusable. The "old-style" radios have a separation between channels of 40 kHz. Today, a separation of 10 kHz is needed, even though R/C channels will still be 20 kHz apart---because the FCC in their infinite wisdom have created channels for pagers and such _between_ the R/C channels, i.e. 10 kHz away from our frequencies. The Airtronics VG4 FM series is an inexpensive example, and is about $120 mail order. [U. S. specific].
If you can afford it, a system that has a "buddy box" is a really good idea. This is an  arrangement where the instructor's radio is hooked up to yours, and he just has to release a button on his radio to take over control, rather than wrestling the radio from your grip. If you do this, be aware that you need to get the same (or compatible) radio as your instructor.

Buying and Building - Plans, kit, or ready-to-fly airplane?

Should I start with plans and build my own plane from scratch, buy a kit plane with wood and plans included, or go with one of those everything included ready to fly planes?
There are a few good trainers that are ready to fly (or almost ready to fly, aka ARF). ARF planes are usually heavy and hard to repair. The new generation of ARF kits is all wood and better built but more expensive. The better kits have parts that are machine cut, the somewhat cheaper ones are die-cut. You'll probably have to so a little more work with a die-cut kit, mostly in separating parts and sanding them.
ARFs vs. kits: this is a matter of opinion, but more people seem to think that kits are a better idea for beginners. Pro kits: you get valuable building experience and are able to do repairs. Moreover trainers are good planes to learn to build as well as to fly, and most of them are cheaper than most ARFs. Pro ARFs: you can be flying sooner, and you have less emotional investment in the plane so when you crash you don't feel as bad.
However: regardless of what you chose, your chances of a painless education are greatly
improved if you have an instructor---both for building and for flying.

Remember, the plane you buy doesn't have to be good looking, it just has to teach you to fly! Many pilots after building a beautiful model are so afraid to crash that they never fly. Far better to have a scummy looking plane that you don't mind crashing again and again and learning to fly than to have a slick model that you can only mount on a stand! After you are proficient you'll have plenty of time to build good-looking planes. It seems to be the general consensus that there are enough decent kits around that, for the beginner, building from scratch is not really worth the effort unless you are into design or obscure scale models. The most important thing you can do while building is to make sure that everything is straight and square. This will result in a plane that flies consistently, predictably, and according to what you do at the transmitter instead of constantly trying to turn! This means: make sure the fin and the stabilizer are at right angles; make sure the wing and stabilizer are at right angles to the fuselage (viewed from above); looking at the side view, the wing, stabilizer are all at the angles specified on the plans; and that the wing is built on an absolutely *flat* surface, to make sure it doesn't have any warps or bends.

Covering

For now, stay with Monokote. It's reasonably easy to apply, comes in tons of colors and isn’t too heavy. (The label gives directions.) Also, if you screwup a bit and find that the wing is warped, you can sometimes fix it by twisting it and re-shrinking the covering to hold it in place.

Hinges

There seem to be as many opinions on this as there ways of hinging! The important thing to watch out for - they should be strong enough so they won't pull out, and the gap between the surfaces should be as small as possible(or preferably sealed). This is yet another place that an instructor/tutor is invaluable.

2) Learning to Fly

The most important point, one which cannot be overstressed:

CONTACT THE CLUB’S HEAD INSTRUCTOR FOR INSTRUCTION, HIS NAME
APPEARS ELSEWHERE IN THIS WEB PAGE!!!!

Here's what one beginner had to say:

" I just started doing RC planes myself. In fact, yesterday I flew my plane for the first time (with an
instructor). He took off for me, got the plane at a real high altitude and then gave me the controls. I
did OK (in my opinion) but did have to give him the controls twice in order to get the plane into
stable flight again. I figured the controls would be sensitive but I did not realize HOW SENSITIVE.
I only had to move them about 1/8 of an inch to turn."

" There is no way I could have landed the thing without crashing. By the way I am a full scale pilot.
That did not help me at all. In fact I think it hurt. I didn't realize how much I use the "feel of the plane"
when flying a real one. Obviously you have no feel whatsoever with RC planes."

"You probably won't have any really bad (i.e.irreparable) crashes. (Of course, you'll still crash.) Also
make sure you have your instructor check your plane thoroughly before the first flight---as
someone said,

"It is much better to go home with no flights and one airplane than go home with one half a flight and
many little pieces." This is really, REALLY important.

Pre-flight Checklist

When your model is ready to fly, make sure it is thouroghly checked over by someone who has
done alot of building and flying. Call the chief flying instructor, he can inspect your plane or
recommend another club member who can do it for you. When I say thoroughly, I don't mean just
picking it up and checking the balance and thumping the “tires” a few times. Every detail of setup and
connection should be gone over in detail.

The importance of this pre-flight check cannot be overemphasized! Many planes are lost due to a
simple oversight that could have been caught by a pre-flight!

Here's a checklist:

Before the first flight:

1.-Weight ... is the model too heavy?
2.-Balance ...
is the center of gravity (fore and aft) within the range shown on the plans?
is the model balanced side to side? (right and left wings of equal weight)
3.-Alignment ...
are all flying surfaces at the proper angle relative to each other?
are there any twists in the wings? (other than designed-in washin or washout)
4.-Control surfaces ...
are they all securely attached? (i.e. hinges glued, not just pushed in)
are the control throws in the proper direction and amount? (usually indicated in the
plans)
5.-Control linkage ...
have all linkages been checked to make sure they are secure?
-are all snap-links closed?
have snap-links been used on the servo end? (They are more likely to come loose
when used on the servo)
have all screws been attached to servo horns?
6.-Radio Checks
has a full range check been performed?
have the flight pack and transmitter pack charge been checked with an expanded scale
voltmeter?
have the receiver and battery been protected from vibration and shock?
is the receiver's antenna fully extended and not placed within a fuselage with any sort of
metallic covering?
7.After repair ... the checklist should be gone through again, with particular attention to the
areas that were worked on or repaired.
8.Before EVERY flight ... Check the receiver flight pack with an expanded scale voltmeter to
ensure enough charge. Check the control throw direction for all surfaces. It's very easy to do
a repair or radio adjustment and forget to switch these.

3) Gliders

a.Introduction
b.Launching
c.Staying Up
d.Recommendations
e.Costs
f.Suppliers

3a)Introduction

A 2-channel (rudder+elevator) polyhedral glider is just about the easiest way to learn to fly, and is
highly recommended. Once you can handle that you can move up to rudder-elev.-spoiler-flap
competition ships or (on the slope) rudder-elevator-aileron-spoiler aerobatic ships.

Sailplane plug (aka religious sermon): ... don't think glider flying is just "launch, glide back"---It's very
easy to get 30+ minute flights and about 1000' altitude. Remember, power flying is limited by the size
of the fuel tank (about 10 minutes) and gliders are limited by the receiver batteries (about 2 hrs).
And glider flying is *much* more challenging (my opinion, of course), while at the same time being
easier to learn. And no fuel costs, no starting hassles, no cleanup afterwards... Also, many cities have
ordinances prohibiting model engines, which means the flying fields are outside city limits. BUT, since
sailplanes don't have those nasty, messy smelly things, we can fly in any large enough area!

3b) Launching-

Are most gliders hand launched, or do they have a small engine to get them up?

Gliders are usually launched by a "hi-start"---a section of rubber with about 500' of line. It is hooked
to the plane and pulled back---the rubber then pulls it up kite-like. (It is NOT like a catapult
launch!). Launches of heights up to 500' can be obtained on a good day. The launching procedure is
simple---keep the elevator neutral (for now) and keep it flying straight. At the top the glider will just
fly off the line. A small engine can also be used but it creates a lot of drag which is very detrimental
to gliding performance. Hi-starts range from around $20 for light-weight models to $100 for
heavy-duty ones.

Winches are also used---it's very similar to a high-start except that you (the pilot) always have
control over the line tension so you can usually get better launches. It does take more skill, though;
as a beginner you don't need to worry about winches just yet.

Flying at the slope you just chuck the plane into the wind---that's it!

3c) Staying Up- How do sailplanes stay up?

Since a sailplane has no engine, it follows that it must always sink through the surrounding air. The
trick then is to find some air that's going up faster than you'll sink through it... and for our purposes,
there are two kinds of such air:

-air heated locally will tend to rise. The heating could be by the sun on a parking lot or a
bonfire or a .... This is called "thermal soaring"---the columns of rising air are called thermals.
This needs some skill/experience, and mostly involves smooth flying and a good idea of how
your plane reacts. An easy way is to just follow more experienced fliers (some of which are
birds) into them.
-wind striking a slope will rise to go over it. You just fly in front of the slope where the air is
going up. With a steady wind this is easy to fly in, with challenges provided by aerobatics etc.
This is called (surprisingly) "slope soaring." Landing is more challenging while at the slope
unless you have a large field or something at the top.

3d) Recommendation- What to buy? 2m class: Carl Goldberg Gentle Lady, Dynaflite/Craft-Air
Drifter II, Airtronics Olympic 650, SIG Riser, Great Planes Spirit, Dave’s Aircraft Works TG3. etc.
These are all polyhedral ships with rudder and elevator controls. All are highly recommended. Carl
Goldberg Sophisticated Lady: basically a souped up Gentle Lady, it is in general not recommended
for beginners---it's heavier and the T-tail structure is very easy to break, even on a slightly rough
landing. 100" or standard class: These models fly better but are more cumbersome to launch and
transport, and are also slightly more expensive. Try Dynaflite/Craft-Air Butterfly, Airtronics Olympic
II, SIG Riser 100 etc. These are basically scaled up versions of the 2m ships above.

3e) Costs- What kind of cost am I looking at for a solid training glider, with all gear?

$200 is in the ballpark. $99 for a 2-ch radio, $80-$100 for a 2m glider, covering and other supplies.
ARF Gliders---$125 + radio + supplies. A high start will set you back an additional $75.(By
"supplies," we mean things like rulers, knives etc.)

4)Electric Models

Some of the common questions about electric flight:

a.) Isn't this stuff heavy?
b.) What are the advantages and disadvantages of electric flight?
c.) What is the best way to get started in electric flight?
d.) What are the elements of an electric power system?
e.) What support equipment do I need?
f.) Where can I get this stuff?

a) I didn't know that you could put an electric motor and batteries in an airplane. Isn't that kind of
heavy?

Modern NiCd batteries are pretty amazing. You can charge them in 15 minutes, take power out of
them at up to 50 amps or so, and do it all day. That capability is what makes electric flight possible.
Electric power can be used for any kind of flying---gliders, aerobatics, even racing. It's an excellent
choice for sport flying.

b) What are the advantages and disadvantages of electric flight compared to gas powered models?

Electric power systems are heavier for a given power output. This means that planes must be built
lighter, which may be more challenging (especially for the beginner). That's really the only significant
disadvantage. The big advantages are that electrics are quiet and clean.

The biggest advantage of all is that electric flight is unusual and interesting!

c) What is the best way to get started in electric flight?

That depends on what you want to do and where you're starting from. If you've never flown RC
before, and you want to start with an electric plane rather than a pure glider, we recommend a basic
three channel electric glider for starters. This will give you the best chance to stay ahead of the plane.

If you know how to fly RC, you have a lot of choices. The simplest and most available electric
power systems use six or seven cells. These are called "05" systems, and are very similar to the
power system of an RC car. You can find all sorts of planes in kit or plan form which will work well
with these systems. Any two-meter glider kit can be easily adapted to six or seven cell electric by a
moderately competent builder. Just stick a motor in the nose, battery under the wing, and go.

If you want more performance, good ground handling, or just like larger planes, there are larger
power systems available, all the way up to systems which will handle a 60-sized power plane. The
cost and complexity, of course, go up with size. Any reasonably well-designed power plane kit or
plan can be adapted to an appropriately chosen electric power system. The first step is to leave out
half the wood---all power planes are grossly overdesigned. Electric motors generate very little
vibration, which helps you get away with lighter structures.

d) What are the elements of an electric power system?

The power system includes a battery, a motor, a control, and wiring. The battery is almost always
made up of Sanyo NiCd cells in the appropriate number. Motors vary from the simple, cheap "can"
type (otherwise known as "540" or "550" style), through more sophisticated styles adapted from RC
car motors, up to the cobalt powerhouses.

Controls can be a simple on-off switch controlled by a servo, a directly controlled on-off switch, or
a proportional electronic control.

If you are going to fly a glider or old-timer type plane with less than a 500-watt motor, think
seriously about getting battery packs made of Sanyo 900 SCR cells. They are significantly lighter
than the more usual 1200 mAH (sub-C) cells and give excellent performance.

e) What support equipment do I need?

You need a charger of some sort. If you are using six or seven cells, any RC car charger will do the
job. You don't need peak detecting or any of that fancy stuff to start with. For larger packs, there
are good high-voltage chargers around. Check out Astro Flight and TRC, among others.
Remember, the biggest enemy of NiCads is heat, so try and keep those batteries cool when
charging.

f) Where can I get this stuff?

Electric equipment is somewhat specialized, and most hobby shops aren't yet sufficiently enlightened
to carry very much. You can use RC car equipment for a lot of things (after all, they developed this
stuff in the first place) and your local hobby shop will have lots of that. If you want to get more
sophisticated, get the catalogues from Hobby Lobby and Hobby Horn (both have ads in all the usual
magazines.) Both catalogs contain a lot of detailed information that we can't fit in here. Hobby Horn
has good prices on mainstream stuff. Hobby Lobby sells the lines of several European
manufacturers, and tends to have higher prices for fancier (or at least more unusual) stuff. Of course
check the web, E-Zone is an excellent on line magazine with lots of how-to info or speak to club
members involved in the electric scene. Any member can refer you to them.

5)Some (Very) Elementary Aerodynamics

The aircraft can rotate around three axes:

the fore-and-aft axis (or the roll axis);
the spanwise (nose-up/nose-down) axis or the pitch axis;
and the nose-left/nose-right, or yaw axis.

Speed:

The cross-section of the wing has a shape called an airfoil . It has the property that when it
meets the air (usually at some small angle, called the angle of attack, it generates an upward
force (lift) for a small backward force (drag). The amount of lift (and drag) depends on the
airspeed and a value called the lift coefficient (and a few other things like surface area and
density of the air). If the plane is in unaccelerated flight, the upward force (approximately
equal to the lift) is equal in magnitude to the weight of the plane, which is a constant. It thus
follows that the total lift generated by the wing is always constant (at least in unaccelerated
flight). [One example of accelerated flight is Turning, see below ]

The above mentioned coefficient of lift (abbreviated Cl) depends on the angle of attack.
Usually, as the A-of-A is increased, Cl increases; to keep the lift force constant, speed can
decrease. So to fly fast, we decrease Cl (and A-of-A); to slow down, increase Cl (and
A-of-A). Since the wings are fixed, we alter the A-of-A by pitching the entire plane up or
down. This is done with the elevator. The elevator is thus the speed control.

Turning:

To turn a body moving in a straight line, a sideways force must be applied to it. For a plane,
the best method for generating a force is to use the wings. To get them to act sideways, we
roll the plane: now part of the lift is acting sideways and voila! a turn. To roll the plane, we use
the ailerons (the movable surfaces at the wingtips). Also, notice that now since part of the lift
is acting sideways, the lift force in the upward direction is reduced; but the upward component
of the lift needs to be equal to the weight of the plane i.e. we need a little more lift from the
wings, which we can do by increasing Cl---i.e. by pulling a bit of up-elevator. That's why to
turn in a plane you push the stick sideways in the direction of the turn and then pull back a bit
to keep the nose level.

What happens if you try to turn with the rudder alone?

The application of the rudder will cause the aircraft to yaw, and it will continue to travel in the
same straight line (more or less), skidding. (Think of a car on a perfectly slippery road---if
you try to turn just by turning the wheel, you'll skid but won't turn). So we need a roll to turn.
But most of the trainers we see don't have any ailerons! How do they turn? They use a
configuration of the wings called dihedral (or, for most gliders, polyhedral.

When we apply rudder (say left rudder) to a plane with di/polyhedral, what happens?

The plane yaws; the right half of the wing then sees a greater angle of attack than the left half.
(You can try this out if you don't believe it: take a piece of paper and fold it slightly, like
dihedral; then look at it end on, but slightly off-center, i.e. from the point of view of the
approaching airflow. You will see that you can see more of the underside of one half than you
can of the other.) And what does an increased angle of attack do? It increases the Cl and the
lift generated by that half! So we now have the right wing generating more lift and the left less;
the result is a roll to the left. With polyhedral we get the same effect, only to a larger extent.

The Stall:

If you try to fly slower and slower by pulling back on the stick (i.e. applying up-elevator) you
will reach a point where the plane "falls out of the sky" or stalls. What happens is that an airfoil
will only "work" up to a certain angle of attack. When that angle is exceeded, the airflow
above the airfoil breaks up and the result is an increase in drag and a drastic decrease in lift,
so that the wings can no longer support the plane. The only remedy is to reduce the A-of-A
i.e. to push the nose down. This may be a little difficult to do when you see your plane
falling---the natural tendency is to pull back on the stick, to "hold the plane up."
A further development of the stall is the spin. Volumes can be written about it, and have been;
go to the library and check any book on introductory aerodynamics.

If you want to know more about Aerodynamics as it applies to Model Aircraft (the small Reynolds'
number regime, as it is sometimes called) check "Model Aircraft Aerodynamics" by Martin Simons
[Argus Books, ISBN 0 85242 915 0].

6)Suppliers

The club generally likes to recommend suppliers that have supported us as sponsors for various
MATS contests and events by providing prizes, all are reputable:

Locally:

-Ted’s Hobbies and Crafts, Pointe Claire
-Hobbieville, St. Laurent
-Icare Sailplanes, Boucherville
-Dynamic Hobbies, Ottawa

Mail Order:

-Hobby Lobby
-East Coast Model Center, P.E.I.
-Morris Hobbies
-Tower Hobbies

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