How to Convert a Radio Controlled Airplane to a Brushless Motor

Choose a motor and prop combination that will give the plane the same or more thrust than the original motor. An easy way to calculate the power need is to use the general rule of thumb that 3D planes need 150 watts per pound; sport planes require 100 watts per pound and trainers need 80 watts per pound. Most resellers and manufacturers have the brushless motor wattage posted on their websites.

Select an electronic speed controller (ESC) that can handle the amperage draw of the motor you select. If the ESC is rated too low, the protective circuitry will cause the motor to loose power in flight. If the ESC is a budget model the amperage draw may permanently damage the ESC. The amperage draw can also be found on the reseller or manufacturer website.

Select a motor mount that places the propeller in the same place as the original motor. Since brushless motors are much smaller then gas, nitro and brushed motors, mounting the motor in the correct location can be a challenge. Aluminum tubes called stand-offs can be purchased to help position the motor in the correct location.

Position the ESC in a way that air can flow over it and keep it cool in flight. This need differs greatly from nitro and gas motors. Fuel-based motors require the firewall to be sealed so no oil or fuel touches the airframe; in electric-powered planes the ESC and the batteries need to be air cooled. Typically holes need to be drilled in the firewall to allow air to pass.

Balance the plane at the center of gravity. This is essential and more difficult now that the motor has been changed. Brushless motors are much lighter then gas, nitro and brushed motors and the plane will be tail heavy. Place the battery as far forward as possible and add lead weight to bring the plane back into balance.