Earlier this year, FlightPower EON released a whole load of new battery packs to meet the increasing need for more powerful batteries in small electric helicopters. As RC Helicopters evolve so do batteries, it seems, and these new packs are lighter, smaller, and more powerful than ever before.

FlightPower recognise that good things come in small packages, and that the new generation of micro and mid-sized RC electric helicopters are advanced flying machines that need a lot more power than the simple FP helis of old. These latest batteries hold a charge longer, wear out less quickly, weigh less and are more streamlined – perfect for high power indoor flying!

Take a look at this:

FlightPower EONLite: 350mAh – 5400mAh. Lightweight, low cost, and with a high powered performance, these are suitable for everything from foam toy RC Helicopters to 500 TRex models.

EON reckon their well proportioned 870 is great for electric helicopters like the T-Rex 250. Going up the scale, the 3250 isn’t that much bulkier, but promises top performance for models like the T-Rex 500 (evidently, the company likes T-Rex!).

However, for competition flying they’ve just brought out the twin pack EONF3A 5400 Competition range. This is a matched 10s pair of two five packs, with a super lightweight housing and sleek, slim lines.

Unbelievably, it’s not just RC helicopters that win competitions, but the batteries as well. Pilots are sponsored by the battery companies to fly using their products – so if the batteries are good, everyone wins.
Last year, RC electric helicopters flying the 5400’s predecessor took the Italian F3A Nationals, and the US F3C Nationals (piloted by the Grand Master of RC Helicopters, Curtis Youngblood himself).

I wonder how the F3A 5400s will do?

There are several types of motor, of varying quality. The cheaper ones can usually be upgraded.

The very cheapest, which are rarely seen on hobby grade CP RC electric helicopters, are the simple brushed ferrite type. Here, the motor armature is supplied with power via a set of carbon brushes and a commutator. Everything required to make the motor run is contained within the motor itself, and it’s all very simple. If you apply DC current to the motor at the right voltage, it will run. These are about 55% efficient, with the rest of the energy being lost as heat.

A better option for Brushed Motor Electric Helicopters is the rare earth, or brushed cobalt type. These are much better quality, and have powerful magnets made of rare earth materials, silver alloy brushes, adjustable timing and high quality ball-race drive shafts. Although they work the same as the ferrite version, electric helicopters running off these are much more efficient.

Brushed cobalt motors are adjustable, like a car engine. Higher quality magnets mean they are far more efficient – typically 70% or more. This means a cooler running motor with less wear and tear. Again, everything is self-contained within the motor itself.

In both cases the principle is simple. Thus, the speed controller can be simple as well. All you need is something capable of acting as a throttle by turning down the current to the motor. Electric helicopters used to achieve this by means of a servo connected to a wiper-arm resistor.

However, nowadays practically all RC electric helicopters have an ESC, or electronic speed controller. This “chops” up the current going to the motor, thousands of times a minute, telling the motor to be on for a fraction of a moment at a time. Evidently, controlling this pulse rate controls the speed of the motor.

RC helicopters equipped with top-of-the-range cobalt or rare earth brushed motors, especially if they have digital ESC, are often just as good as those fitted with a cheaper end of the spectrum brushless.

If you start looking more closely at the specifications, electric helicopters can become complicated things. What is CCPM, and why are heading hold gyros so special? Here are a few of the things you might find on the average Collective Pitch upgrade.

Digital servos: Often found on advanced RC helicopters with belt driven tails, these quite simply respond quicker, and with more accuracy to commands than standard analogue servos. Much preferred by the 3D fraternity.

Heading Hold/Lock Gyro: Normal “rate mode” gyros just dampen the yaw of RC helicopters, without taking into account the heading that the pilot is trying to maintain. HH Gyros digitally store the heading hold information, constantly attaining that heading by inputting signals to the tail servos. Very advanced, maybe a bit too much for novice pilots of electric helicopters to cope with.

Brushless motor: On safer ground here. RC helicopters with brushed motors wear out quicker. Brushless is always best, even on the most basic, 3 channel electric helicopters. If you buy a heli with a separate tail motor, make sure it’s brushless (or upgrade).

ESC: Electronic Speed Controller. Often included in descriptions of RC helicopters, but not strictly necessary. All motors – brushed and brushless – have these. Otherwise, how do you vary your speed? What you are looking for is a BEC, or Battery Eliminator Circuit. These allow all the electronics to run off one power source (i.e. the main battery). Again, most electric helicopters have these anyway.

2.4GHZ Transmitter: Means you’re not confined to a set RC wavelength, so can fly with anyone, anywhere, without risk of interference. 35GHZ RC helicopters are immune from your transmission signal, as you are from theirs. You also get less interference from mobile phones and other electronic gadgetry – a big plus!

Most of the more expensive, 6 channel CP electric helicopters have upgraded mechanics and electronics – but what do all those extra words mean?

To take you through the jungle, we’ve “dissected” one of the best RC electric helicopters around – the ESky Belt. As well as explaining what some of the terms mean, we’ll show you what to look for when reading through the “specs” for electric helicopters in general.

First of all, don’t worry too much about gearing ratios and so on – at this stage in the game, it’s the more obvious differences that we’re looking for.

Let’s start by looking at the name: the ESky Belt CP V2. V2 means it’s the latest version. Belt means that, in this version the tail rotor is belt driven from the same motor that drives the main blade. Most of ESky’s RC helicopters have separate motors to drive the tails, so this is a big improvement.

Why? Well, firstly it means more power to the tail rotor (most tail motors are underpowered and burn out quickly) Secondly, it means more sophisticated mechanics, with a gearing system to vary the tail speed, and separate servos to adjust the yaw.

Belt RC helicopters are available in two formats - 35MHZ or 2.4GHZ. This refers to the transmitter - 35 MHZ can interfere with other RCs on the same wavelength, while 2.4GHZ causes no interference. Overall, it’s worth paying the extra for the 2.4GHZ. One day, all Electric Helicopters will be built this way!

Digital servos: Here, the servo balance is adjusted by digital electronics; analogues apply a variable voltage to the motor. RC helicopters equipped with digital servos respond faster to commands, and are more sensitive and manoeuvrable, than those running on analogue.

Competitions are excellent places to put everything you’ve learned about electric helicopters into practice. But, they can also be terrifying!

Ideally, you will have a 2.4 GHz transmitter, which makes finding your place in the order of things a whole lot easier. Even if you accidentally get in the wrong class, it won’t matter too much!

Remember, you won’t be the only one flying. There may be hundreds of RC helicopters being put through their paces besides yours, with maybe 4 or 5 in the air at the same time. Thus, it’s essential your transmitter frequency doesn’t interfere with anyone else’s. With a 2.4GHz, of course, that doesn’t matter.

If you’re flying with a conventional Tx, you’ll need to collect your transmitter from Tx control well before flying - and double check your place on the peg boards. Next - make sure you have your spotter to hand, and they have a copy of the schedule you’ll be doing. Make sure they’ve got the right one!

When it’s coming up to your turn to fly, you’ll be told to take your place at the line. You may be in a mixed fuel class, or one specific to RC electric helicopters. If it’s mixed, you might hear a call to “fire up” your RC helicopters. Don’t worry - just make sure you’ve got a fully charged battery and are trimmed ready to go.

You’ll be told to take your place in the pilot’s circle - generally, this is 20M away from the flying box. Place your helicopter on the take off/landing circle and switch her on. Now, return to your position and wait for the start order.

Once electric helicopters are started up, the pilots are allowed five minutes to hover and trim their choppers in the start circle. Once this is done, the spotter calls “beginning now” to the judges, and the test begins.

Your spotter will call each manoeuvre as you start it, and again when you finish. There is usually a set time to complete the schedule - evidently, points are deducted for foul-ups.

After you’ve completed your final manoeuvre, your spotter will call “flight complete.” Switch off and leave the area as quickly as possible.

Everyone who flies competition RC helicopters swears there’s no buzz like it - so next time there’s a Fly In near you, have a go!

Whether you are competing or just a spectator, RC helicopters are a lot more fun if you understand what’s going on.

Competitions always take place over a central “box” – a marked out square with a central landing/take off area. The flags or markers you see are important – they are referral points for the different manoeuvres, and points are awarded or deducted depending on how accurately the RC helicopters fly over them.

You’ll be pleased to know that electric helicopters are ideally suited to competitions, as very few are exempt. The only stipulation is that power systems must be 42V or less, with a 6Kg weight limit. There is no minimum size. Practically all 450 RC electric helicopters are eligible for all classes of competition – including FAI. It should be noted that RC helicopters equipped with virtual fly bars and electronic stabilisation are not allowed. Gyros are permissible on the tail rotor only.

The first task is a quick visit to Tx control (where your radio frequency will be recorded, for pegging out) This applies even if you have a 2.5GHz transmitter, and is important for what comes next – the order of play.

A small competition will probably call the entire field as one group. Larger events call each class individually. In more serious BMFA competitions this may be preceded by a pilots’ meeting. The drawing order is completely random, apart from the obvious considerations towards radio frequencies.

From then on, things can get pretty hectic. If this is your first competition, it is best to have a buddy who understands the ropes. You can be penalised for not being ready on time, so make sure you know exactly what is expected of you, and where you should be, right from the word go.

Remember, electric helicopters are all about having fun, so don’t get too worked up about it!

Although the following notes are gleaned from US AMA competitions, they are very similar to BMFA events in the UK.

The order of flight is completely random. Although there is some room for manoeuvre, you must remember a lot depends on the radio frequencies of the individual RC helicopters. Evidently, the more 2.5GHz transmitters there are on the field, the easier it is to vary the order. It is a good idea to have a few spare crystals with you, in case your designated frequency is a popular one!

For two day events, there are generally 5 competition rounds. Small local contests may have manual scoring, but big public events often use a computerised system.

Most clubs for RC electric helicopters are BMFA sanctioned. Therefore, BMFA membership and insurance are required, as are proof you hold the BMFA Certificate B (for flying RC helicopters at public events).

Electric helicopters are flown one at a time from the flight box. There can of course, be more than one flight box in operation at the same time (and generally are, provided there are enough judges), but the Radio Control Helicopters must be on different frequencies (if applicable).

It is usually expected that you have a caller or spotter. This person will call the manoeuvres, make sure you don’t collide with other RC helicopters, and make sure you don’t break the rules (for instance, by stepping outside the box). This allows both you and the judges to concentrate on the 3D action. Your spotter should know that calling isn’t just for the benefit of the pilot. They also have to call the beginning and end of each manoeuvre to the judges.

If you don’t have a spotter, don’t worry. There’s always a willing volunteer – just remember to have a calling sheet, so they know what to do.

Many beginner pilots decide, after looking at 3 and 4 channel RC helicopters, to splash out on a 6-Channel collective pitch model and have done with it.

Whilst intermediate to advanced level electric helicopters are trickier for novices to learn on, they do offer a level of flexibility not seen on cheaper models.

For example, RC electric helicopters (including co-axial) are equipped with a fly bar, which will ideally be generously “weighted” or have adjustable weights – both offer additional stability. The helicopter is at its most stable with the weights at the far ends. As you become more adventurous, you can move the weights inwards – or dispense with them altogether. Heavy weightless fly bars are easily upgraded to lighter, weighted ones, by the way.

If you’ve purchased an intermediate level 3D machine like the ESky Belt, you may find the fly bar insufficiently weighted. Many electric helicopters are equipped with plastic weights, which are next to useless. All this is easily remedied – metal fly bar weights are widely available and easy to attach. Don’t be tempted to “cheat” with lumps of Blutac (Though it is useful in an emergency).

Some more advanced RC electric helicopters also have the option of Bell-Hiller Ratio Adjustment. The Bell-Hiller mix adjusts the ratio of pitch input from the swashplate to the input from the fly bar. The best RC helicopters have a Bell-Hiller head, although both Bell and Hiller single systems are available.

In a Bell system, the swashplate connects directly to the rotor blade grips, bypassing the flybar. RC helicopters built this way are extremely manoeuvrable, but not very stable. These “flybarless” RC helicopters are rare – but have been included to explain how the Bell-Hiller system works.

Most beginner electric helicopters have a Hiller head. Here, the swash inputs go to the flybar, which in turn inputs to the main blade grips. They are stable, but not very responsive – though upgrades are possible.
Hence, if you are going to buy a more advanced heli as your “start up” chopper, go for a Bell-Hiller head and adjust the mix to give a high Hiller input to begin with. This means the rotor head is governed mainly from the fly bar, meaning a stable predictable flight pattern.

These are just two of the ways electric helicopters designed for the Air Ace can be temporarily “downgraded” to suit novice pilots.