If you are learning to drive a car all by yourself and even if you dont have anyone around to teach you and once on the roll if u feel you can't manage to drive atleast you can switch off the car and take your foot of the accelerator pedal and the vehicle will jerk to a halt harming no one exxcept a lttle embarrasment maybe. But in aeromodeling you can't switch off or take your hands off the controls because the moment you do that your plane will crash into the ground leaving you with a big hole in your pocket and probably no help again to get started. All I wish to emphasise is that the aeromodeling is not something you can do "out of the box" . Read on to see what you need to get into it.
A Radio Control Plane can be divided in three sections
1. The plane itself or the model
2. The Engine
3. The radio control or simply the radio
These three come together to make the whole package of an aeromodel. Important Costing information
The Aeromodel : The plane is usually made of a special type of wood called BALSA which is very light and soft. Planes are also made of other materials like fiberglass, Plastic (spad) but these are usually heavier than BALSA ones hence not so popular.
The beginner starts with a plane called the trainer which is basically a model with good slow flying controlling charterstics. The trainers have their wings mounted on TOP of their fuselage which is the main body of the plane.This configuration is called High Winger. The top wing makes it easier for the plane to stabilise and usually when the plane is turned will give it a tendency to level out and stabilise because its Centre of Gravity(CG) is below and towards the middle of the wing.
The wing of the trainers is also different. The cross section of the wing called the aerofoil which is the view if you slice the wing breadth wise or look at it from the side, has a curved top and a flat bottom. This kind of design gives the plane a good slow flying trait (when i mean slow it means speeds upto 60 kmph)
The front edge of the wing is called the Leading Edge (LE) and the back edge the Trailing edge (TE). When the air moves across the wing by virtue of the plane moving forward, the air across the top has to move a little more then the air at the bottom of the wing and hence it creates a low pressure while the pressure at the bottom of the wing remain constant or relative to the top become higher pushing the wing upwards ... giving it lift andthis is basically the principle behind flight. Of course this is very basic and there are a lot of other paramaters that govern wing design, however keep this in mind and move forward.
The length of the wing wing tip to wing tip is called its SPAN , the breadth ie the distance between the LE and TE is called the CHORD. You must have seen wings that taper or don't not have the same cross section through out their span. narrowing toward the tips. The Chord in the middle of the such wings is called the ROOT CHORD while the chord at the wing tip is called Tip Chord.
For a beginner trainer the Wing Span is engine dependent but usually 40/46 sized engines in India have wingspans between 40" to 60". The length of the fuselage varies between 36" to 46 "
Planes have a stabiliser at the rear which is a small horizontal wing at the rear of the plane. The vertical fin you see is called the rudder . The stabilser has a small control surface that moves up-down called the the elevator while the vertical fin has a control surface called the rudder which moves the plane left or right. The elevator is the main part controlling the plane to move it up or down. The wings have 2 control surfaces on the TE of both sides that also control the left and right movement of the plane. To know more about Plane design read this
Now that you know something about the planes you can go in for an ARF that is ALMOST READY to FLY planes as trying to build your own plane is not advised for RC beginners coz u need something with proven flight qualities for learning.
Most trainers will cost you between Rs 2500 to Rs 4000. Don't go in for a fancy plane as there are sure to be minor or maybe even major scrapes and crashes along the learning curve. Believe me even experts crash so it s Ok for you to have them once in a while.
Engines : The Engine is your muscle and heart of your Plane. Choosing one that will last you beyond your training and next 5 years is an important decision. You must read introduction to Engines for details on how engines work.
In the Indian context we usually buy just one engine as they are quite expensive so it is important to buy an engine that will fit on something beyond your Trainer. The engine should be easy to start and give you good high end as well as equally good idling charterstics. There are a lot of good engines available abroad but I have seen most, if not all Indian RC modelers prefer OS Engines. These are reliable and last you for almost 5 -10 years if taken care of properly.
I would recomend the OS 46 FX 2 stroke engine to all as it is the right engine with almost 1.6 HP runs at around 16000 rpm for most planes with wingspans betn 40" to 56". OS 46 also has a cheaper brother the OS 46 LA which costs about Rs. 1500-2000 less but this has bush bearing instead of Ball bearings for the crankshaft of the engine and they become unreliable pretty soon.They also have plastic parts that break off and also have airleaks. Since you are buying just one buy the FX.
A word about the smaller engines like the 25 / 15 /10 sizes . Most beginners may feel that smaller the engine, more controllable the plane or maybe the lower cost may attract them to them. However I would advice you against it . Its like buying a Luna to learn riding and very quickly outgrowing it.
Ther are 4 stroke engines also however they are for veterans and quite expensive. you can move on to them later.
Radio : The nerve centre and brain of your Plane. The radio basically consists of the following
1. Transmitter
2. Receiver
3. Servos
4. Batteries
5. Chargers
The radio basically is the Transmitter TX which houses the controls of the planes. Most Planes require 4 channels ie 4 parameters to be controlled to fly. The controls are
1. Throttle control of the Engine
2. Elevator of the Plane
3. Aerilions on the wings
4. Rudder
There are more parameters like Flaps, wheel retracts that can also be controlled on advanced planes but most for frills and you can do without.
Also important is to not get stuck with a 2-3 channel radio sometimes attractive to beginners due to their lower cost or lack of information.
The radio will last you your entire RC hobby and can be used in your next plane. Stick to a good brand like Futaba, Airtronics.
The radio also has a receiver which is housed in the plane and controls the servo motors that move your control surfaces on the plane. This RX is matched with your TX and will not work on another TX unless they work on the same frequency.
The radio ultimately control the servos which are precision motors that move through just about 90 degress unlike other motors that rotate. Varing the Tx one controls which servo to move and by how much. Your servos are matched on your Rx and may or maynot work with other RX.
The radio are basically powered by chargable cells . The TX has its own battery while the Rx has a smaller one. Both of these should be chargable of Ni-Cad or better technology. Be adviced against going in for Dry Cell radios these will cost you less but you will pay every time you want to fly and if unfortunately your half used dry cell finishes in flight you will certainly lose your Plane.
Futaba radios are quite reliable and used by most Indian modelers.
