BEGINNERS - FIXED WING
Type of Power
IC Engines
Probably your first decision is whether you want an aeroplane
which uses an internal combustion (IC) engine or electric
motor / motors to power it.
The vast majority of model aircraft use IC Glow engines,
which run on fuel. This fuel (Glow fuel) is quite different
to petrol, it basically is a mix of Methanol and oil. It can
also have Nitromethane added to enhance power and the engines
throttling ability. A Glow plug is initially powered by a
power source (1.5v). When the engine is turned over the Glow
plug ignites the fuel/air mix. Once the engine is running
the power source can be removed as the glow plug can retain
heat between firing. Petrol fuelled IC engines do exist but
generally only in large sizes designed to power large model
aircraft.
Glow engines come in two formats, 2-stroke and 4 stroke.
Whilst 4-stroke engines are increasing in popularity, they
tend to be quite a lot more expensive than 2-stroke engines
and are slightly more complex to maintain and operate. 2-stroke
engines are the most common model engines found on aircraft.
They are simple, easy to operate and maintain, and are relatively
inexpensive. They are powerful and operate at a high RPM,
the trade off being that they are quite noisy but virtually
all modern engines are supplied with a good silencer.
Picture of a typical 2-stroke engine. Picture
of a typical 4-stroke engine
To start a model glow engine you will need to purchase several
extra items. A lot of model shops do "Starting Equipment
Deals", in which these items are included. Firstly you
really need a "Flight Box" (Tool Box) in which you
keep all your starting equipment and any relevant tools etc.
You will need a 12V battery, a starter motor (held in your
hand which spins the engine over), a "Power Panel"
(This unit has a fuel pump in it to refuel / empty your models
tank and plugs for the starter motor). Finally you will need
either a Glow lead to plug in to the Power Panel or a separate
battery Glow driver (to supply the power to the Glow Plug).
All this will cost approximately £65 plus, so be aware
that you will need to budget for this as well. Once bought
however the equipment will last for many years.
Electric Motors
Electric Motors have only recently become a truly practical
form of power for model aircraft, with the ever-increasing
performance of battery technology. Electric models that are suitable
for learning to fly with can use either one or two motors
to power them, depending upon the design. Electric power is
usually provided by a series of battery cells made up into
packs. Six to eight cell packs are most common. Standard flight
times are around 5 - 12 mins when using electric power. Generally
an electric powered aircraft won't have the same power to
weight ratio as its IC powered counterpart. To achieve those
standards of power requires more expensive "Brushless" electric motors.
Whilst "Brushed" and “Brushless” motors are not very expensive when
compared to IC engines, the battery packs to power them can be.
Picture of a typical electric motor.
An initial disadvantage of using electric power is that you
will need to purchase several extra items. The device that
controls the power supplied to the motor / motors, is known
as a "Speed Controller". This is an electronic device
and can vary in price depending on the power requirements of the motor / model. In order to quickly charge your
battery packs (taking between 30 - 60 mins) you will also
need a suitable battery charger. This can also be quite expensive, but a good quality charger is a sound investment.
These relatively expensive purchases are mostly initial costs. Once you
have purchased them they should last many years. The main
advantages of electric models are that there are virtually
no running costs and they are extremely quiet in operation.
So quiet in fact that our club allows the operation of electric powered models from 7.00am –10.00pm, whilst IC powered models must adhere to more limited flying times.
Which is the most suitable for the beginner?
Due to the relatively low cost, high power output, ease of
maintenance / simplicity, we would recommend that a beginner
should purchase a 2-stroke Glow engine. Bear in mind that the price can be representative
of the quality of engineering and manufacture that you receive.
Although the more economically priced engines are rapidly
improving, their quality is still on the whole not up to the
standard of the class leaders that allow trouble free running in a beginner’s model.
