Much has changed in the world of electric-powered, radio-controlled aircraft since SILICON CHIP last visited the subject back in 1992.

If readers may pardon the play on words, electric flight is undergoing a quiet revolution; a revolution so radical that the economic viability of internal combustion (IC) motor manufacturers must surely be under threat.

This startling transformation has come about as a result of a number of electric flight technologies coming of age almost simultaneously.

Of these developments by far the most important are:

[1] Application of Rare Earth magnets to brush motors

[2] High power, low-on-resistance FETs

[3] Microprocessor-controlled smart speed controllers and smart chargers.

[4] Brushless motors

[5] Battery technology improvement.

Prior to 1992 electric flight was in the hands of a small group of dedicated contest flyers. Today’s electric flyers owe this group a huge debt of gratitude, for without them electric flight would be nowhere near as advanced.

It was this group and in particular, Peter Blomart of Belgium, that established the internationally recognised class of F3E competitions in 1986.

Since those early days of primitive hand made soft start switches and analog electronic speed control (ESC), progress has been staggering, to the point where the modern microprocessor speed controller can now distinguish between brush and brushless motors and configure itself accordingly.

International R/C aerobatic competitions have long held their place as the most prestigious R/C events. While traditionally dominated by IC motors of ever larger capacity and power, it is increasingly common for electric powered models to snatch places from the IC brigade in these showcase events and it is here that the real threat to IC motor manufacturers is developing most rapidly.

The radio-controlled boat boys have also been hard at it. Currently the fastest R/C boat in the world is electric, with a speed of 120.7 mph.

In Australia, Ray Cooper of Victoria set a world record for electric-powered models in the distance to goal and return class with a flight of 54.3km (108.6km total), lasting 1 hour 22 minutes.

Across the world, R/C flyers are scrambling to emulate their international heroes.

Manufacturers of electric motors are springing up like mushrooms and battery manufacturers are continuing to confound, with batteries that are lighter, with more capacity and higher cell voltages. Manufacturers of the chargers for these batteries are hard-pressed to meet demand and so the bandwagon has been set in motion.

With all this going on, the time has come to review this wonderful world of ultra mobile electrons in the most practical way possible: building and flying an electric powered model suitable for park flying on those quiet, wind-free evenings that are an R/C modeller’s special delight.