| Year | 2014 |
| Date | 04-Apr |
| Volume | 212 |
| Issue | 4,479 |
| Page | 506 |
| Category | Electrical |
| Part | |
| Title | Making a Contra-Rotating Electric Motor |
| Author | John Rutter |
| Notes | Modifies readily available motors for flight. Choose the right motors, the extension, which propellers? References |