BEGINNERS - HELICOPTER
Type of Power

IC Engines

Probably your first decision is whether you want a helicopter that is powered by an internal combustion (IC) engine or an electric motor.

As with model aeroplanes, the vast majority of model helicopters 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 helicopters.

                   

Picture of a Typical 2-stroke Heli engine

Picture of aTypical 4-stroke Heli engine

Glow engines come in two formats, 2-stroke and 4 stroke. Whilst there are a few helicopters designed around 4-stroke engines, the engines themselves are slightly more complex to maintain and operate. 2-stroke engines are the most common model engines found in helicopters. 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. Most helicopter engines are not supplied with a muffler from the engine manufacturer. Different designs of helicopter have the engine mounted in different orientations and therefore a standard engine muffler would not always be suitable. Several helicopter kits are supplied with a muffler purpose made by the helicopter manufacturer for use with their particular model. If however no muffler is supplied then you will need to purchase one suitable for your chosen model. This is actually quite an easy task as generally there is plenty of choice available from several manufacturers. The manufacturers denote which brand / design of helicopter each muffler is suitable for on their packaging. Most modern mufflers have been designed to reduce noise as much as possible without detracting too much from the power output of the 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). Certain designs of helicopter may also require a separate extension shaft with a hexagon fitting that “plugs” into the starter motor to turn the engine over for starting. The relevant items required will be laid out in the instruction booklet of your chosen model. All the extra starting equipment can add considerably to your costs so be aware that you will need to budget for this as well. Once bought however the equipment should last for many years.

Electric Motors

Electric Motors have only recently become a truly practical form of power for model helicopters, with the ever-increasing performance of battery technology.

In respect of models that are suitable for learning to fly with, there are now several to choose from. There are micro electric helicopters available, which are primarily designed for use indoors. Whilst these may appeal it is still considered that due to their small size they can be somewhat less stable than a more traditional model helicopter, thus making them less suitable to learn to fly with.

The current trend is towards electric helicopters similar in size to 30(cu in) – 50(cu in) IC engine powered designs. These helicopters are therefore more stable with their increased size. There is a drawback however in that to achieve the standards of power required necessitates the use of more expensive "Brushless" electric motors and a relatively high number of battery cells. The battery pack can therefore also be quite expensive. As the battery will require recharging, most modellers prefer to have at least 2 separate battery packs, thus allowing the removal and recharging of one, whilst the other charged pack can be fitted to the helicopter to allow another flight. The obvious drawback being the extra expense of further battery packs.

Picture of typical Brushless electric motor.

If you choose to buy an electric powered helicopter, you will need to purchase several additional items to the motor and batteries. The device that controls the power supplied to the motor is known as a "Speed Controller". This is an electronic device and can be quite expensive. Brushless motor manufacturers may recommend which specific Speed Controller you should purchase. Before purchasing any equipment you should contact a model shop which has specialist knowledge of electric helicopters and Brushless motors (if required) for advice.

In order to quickly charge your battery packs (taking anywhere between 30 - 60 mins) you will also need a good quality battery charger, which must be capable of meeting your requirements. This again can be quite expensive. A good battery charger is a sound investment though and may even help prolong the life span of your batteries. These expensive purchases are mostly initial costs. Once you have purchased the items 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 strict 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 to model helicopters should choose a 2-stroke glow powered helicopter for their first model.

The size of engine you will need to purchase will depend on the type of helicopter you choose. Generally most helicopters intended for learning to fly with are designed as “30 Size” helicopters, i.e. they are powered by a 30 cubic inch capacity engine. The actual engines from differing manufacturers range from 32 - 39 cu in or 45 – 53 cu in, all of which are suitable for those sizes of helicopter. As with most things in life, you tend to get what you pay for. There are very cheap engines available but unfortunately 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.