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Beginner's Guide: Getting Started

Part 2

By Andrew Gibbs


What will you need to buy?
To get started in electric modelling you’ll need the following:

(i) A suitable model, along with a few tools and glues etc to build it.
(ii) A suitable power system: motor, prop driver & suitable prop, battery, speed controller (ESC) and connectors.
(iii) A charger, plus a suitable balancer.
(iv) A suitable ‘field’ power source for your charger. A 12V battery is a common choice. You may also like to acquire a mains powered 12V power supply for workshop use.
(v) A set of radio control equipment.

Let’s look at these one at a time:

One day – but perhaps not just yet!

Model type
If you want to learn to fly, then your choice of model type is important to maximise your prospects of a becoming a competent RC pilot. Its important to be level headed about this choice, otherwise you can find the business of learning to fly very unsatisfying. However appealing a Spitfire may be, unfortunately it’s not suitable as an aircraft to learn with. In the full-sized world of flying, new pilots start with a trainer, and in the same tradition we model pilots are best off with the same approach.

Generally, suitable training models are high winged types which are purpose-designed for the job. The particular requirements of a training model are:

a) It should be as easy to fly as possible, with good natural stability. This generally means a high wing design with broad chord (the front to back dimension) wings for easy handling and predictable stall behaviour. However, not all high wing aircraft are suitable for training, so choose with care.

High winged models aren’t always trainers. This Decathlon is fully aerobatic – lots of fun for the experienced pilot but not a suitable model for beginners.

b) It should be large enough to be sufficiently docile, easily seen and able to deal with turbulence and gusts, yet small enough to be practical and reasonably able to withstand the rough and tumble of training. These requirements mean that medium sized models tend to be favoured, the ideal wingspan probably being somewhere between 40 and 65 inches (100 - 163 cm). All else being equal, models towards the larger end of this range will be significantly easier to fly for a beginner. Smaller models may require hand launching and so offer less opportunity to learn about take offs. Powered gliders can safely be a little larger, perhaps between 55 and 72 inches (140 – 180 cm) wingspan.

c) It should have sufficient power – but definitely no more than this. Overpowered models are much harder to learn with and excess power should be avoided like the plague. Don’t be tempted to fit more power than you need, reasoning that you can always throttle it back – this is rather like saying you can learn to drive in a Ferrari, provided you keep a light foot on the throttle!

d) It should be robust and able to withstand heavy landings reasonably well. A well designed model, whether made of foam or balsa will be able to do this, although a hard crash will badly damage almost any model. All else being equal, smaller models tend to do much better in this respect than larger ones, especially if they are made from resilient foam.

e) It should be easily repairable. Kit built balsa models can be excellent in this respect. One of the main reasons for this is that if you built it, you’ll be intimately acquainted with its construction so you’ll have a much better idea of how to repair it. For similar reasons, balsa ARTF models tend not to score so well. Also, matching covering material can be hard to find, though this may not particularly bother you, especially if you like the idea of recovering the model. Foam models can be quite easy to repair, although they can start to look scruffy quite quickly around the joints.

With the above requirements in mind, let’s have a look at the choice of suitable model types for training:

Electric powered vintage style models such as this scaled down Lanzo Record Breaker can be delightful to fly, as well as being excellent training tools.

A. Vintage or ‘Old Timer’ style of model
Vintage models were generally originally designed for free flight (i.e. completely uncontrolled), and so possess plenty of natural stability. Such a model would typically be a three channel model with controls for rudder, elevator and throttle. It would use ‘built up’ (traditional, balsa framed) construction and be approximately 60 inches in wingspan. Because of the slow flying speed of vintage types, they don’t tend to come to much harm in a heavy landing, so its fine if they are a little on the larger side. Both almost ready to fly (ARF/ARTF) and kit models are available.

I believe this style of model is unquestionably the easiest to fly and is very suitable for the mature modeller - three channels are quite enough to cope with when learning to fly and such models also have excellent flying characteristics for a beginner – their slow flying speed coupled with plenty of natural stability give a new pilot time to think. This type of model allows take offs and landings to be practiced much more easily than with smaller alternatives.

With this style of model it’s also possible to successfully use either a modern brushless system, or else a ‘traditional’ brushed motor and suitable ESC. Standard RC gear with standard size servos is quite acceptable. Wings are held on with shock absorbing rubber bands and this, combined with a slow flying speed gives a valuable measure of resistance to damage in a crash. The nostalgia aspect of this type of model may also be attractive to the mature modeler, although younger pilots may understandably prefer a different style of model. An example of such a model is the Junior Sixty.

B. Electric powered glider

Electric powered gliders are another suitable option for beginners. A typical suitable example would also be a built up three channel model (no ailerons) up to around 72 inches span.

One advantage of electric gliders that they enjoy inherently very low aerodynamic drag, so very little power is required to fly them. Consequently, long flights may easily be obtained even with inexpensive equipment. They usually fly slowly, giving plenty of time to think. However this low drag also means that they will tend to gain speed relatively quickly in a dive. The low drag can also make for landing difficulties if this has to be carried out in a confined space. Also, they are not generally as robust as a vintage style model. Electric gliders must be hand launched, so they don’t allow take offs and landings to be practiced.

This electric powered glider is another suitable model for training. The propeller folds back, reducing drag for the gliding portion of flight. Note the wings are held on with rubber bands. This type of model doesn’t handle wind as well as other model types, so if your site is windy this may not be the best choice for you.

Powered gliders typically have a little less natural stability than a vintage style model and the higher aspect ratio (long and thin) wing may tend to make pitch (elevator) control more sensitive, so elevator movement may need to be small. Again, standard size servos are quite acceptable unless opting for a smaller model.

This type of model can use either a brushed or brushless system. Brushed power systems used to be the only choice for this type of model, usually employing a ‘600’ motor and a 7 cell NiMH pack. This type of system is still available, but it isn’t really the best choice any longer. While it will work well enough for initial training purposes, it doesn’t make sense to invest in obsolete technology which will probably have no practical use for later models. It’s much better to install a modern brushless system from the beginning. This will be a lot lighter, allowing slower flight, and more importantly greater crash resistance.

C. ‘Standard’ Electric trainer
Until recently, electric models designed specifically for training purposes weren’t all that easy to find. Happily they’re much more common now that manufacturers have woken up to the demand for them. By ‘standard’ electric trainer I mean a model which is a direct equivalent of the standard i.c. trainer, which is generally a 0.40 (over) powered 4 channel design (i.e. with ailerons) spanning about 55-60 inches.

These models are relatively easy to fly, but nevertheless they generally don’t have the very forgiving flying characteristics of vintage style models. Their ‘modern’ appearance probably gives them more appeal for younger pilots, for whom their minor disadvantages are probably of less concern, especially if experienced help is to hand for early flights. Models of this type are usually built up (balsa) ARTF types. If you choose to go this route then a brushless power system is the way to go.

Multiplex’s all foam MiniMag

D. All foam electric trainer
Several all foam electric trainers are now available. These are typically supplied as quick assembly kits, comprising a small number of moulded foam components. Three good examples of the genre which are eminently suitable for training purposes are Mulitplex’s Easy Star (54”, 3 channels, very docile), MiniMag (39¾” span, 3 or 4 channels, slightly sportier) and Mentor (64” span - larger, so better for take offs and landings).

The foam used is a resilient type and therefore relatively crash resistant, plus the models aren’t too large. These models are excellent choices for beginners, especially if you want to ‘go it alone’. Of course, they won’t appeal to the traditionalist for whom models have to be made of balsa but they are undeniably good models to use for training purposes.

Again, I’d recommend a brushless power system in all cases for these models.

This delightfully simple park flyer is made from a few small sheets of blue foam. With a small brushless/LiPo power system this was a very cheap model to build, and didn’t require a huge investment in time either.

E. Park flyers
Finally, a mention must also be made of the so called ‘park flyer’ models. Park flyers are generally up to about 36 inches in span and always light in weight. They’re available in a variety of types, from quick assembly foam kits to fully assembled and totally ready to fly models. The choice of models includes relatively docile models that could be used for training purposes. Due to their small size, these may not be ideal trainers and will tolerate very little wind, but nevertheless they can be a viable way to learn to fly. One big advantage of such smaller, light weight models is that they are inherently more crash resistant.

 

 

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