In previous articles, I've shown you how to convert a toy store glider to RC and how to use that glider for learning to fly. After you've spent a little time with the glider, you should have a much better understanding of what it takes to fly an RC model successfully. In this final installment of the series, I'll show you how I added a power system to give the model longer flights, a wider performance range, and more control.
The glider I've been using is the Air Hogs Titan. Just like every other aspect of the conversion to RC, I approached the power system with the aim of keeping everything as simple and straightforward as possible. What results is an affordable, functional and well-behaved model that is not likely to overwhelm RC newcomers.
Power to the People
I was really happy with the power system that I installed in my Airplane! model (another chuck glider conversion), so I decided to repeat it here. It consists of an ElectriFly Rimfire 250 brushless motor, a GemFan 5x4 propeller, a 3S-500mAh LiPo battery, and a Flight Power 6-amp Electronic Speed Control (ESC). This particular ESC is no longer made. The Castle Creations Thunderbird 9 is a good substitute.
The ESC has a Battery Eliminator Circuit, which provides power to the onboard radio gear from the flight battery. This allowed me to get rid of the 4-cell 1100mAh NiMH battery that previously powered the radio. In fact, the combined weight of the new power system components is within a gram of the weight of the NiMH battery alone. So the Titan is no heavier as a powered model than it was as a pure glider.
Rather than locating the motor in the tail, as I did with my knotted airliner, I decided to mount the Rimfire to a pylon on top of the fuselage. Among the benefits of this configuration are short wires and minimal weight distribution. The high location also helps to keep the motor out of the dirt and grass during landings (and crashes). The only significant tradeoff of the pylon-mounted motor arises when you launch the model. I'll talk about that a bit later.