Chapter 06 · Components
The brain
The flight controller receives commands from the radio, reads the gyro thousands of times a second and works out how much power each motor needs.
Processor
| Chip | Who it’s for |
|---|---|
| F4 | Powerful enough for a 5" freestyle drone. Cheap, but with few serial ports. |
| F7 | More UARTs and more room for peripherals: GPS, digital VTX, receiver. |
| H7 | The most powerful, with headroom for future features and more demanding firmware. |
What to look for
Gyro
The most important sensor. The most common models today are the ICM-42688-P and the BMI270, both well supported by Betaflight.
UART ports
Each serial peripheral needs one: receiver, VTX, GPS. Count them before you buy.
OSD
For analogue video, the board needs an OSD chip. Digital systems handle it in software.
Regulators (BEC)
5, 9 or 10 V outputs to power the camera, VTX and receiver without adding extra boards.
Blackbox
Flash memory to record flight data for tuning.
Connectors
A digital VTX plug, an ESC plug and well-spaced pads make the build much easier.
Stack or AIO
Stack
Flight controller and ESC on two stacked boards. It’s the format for 5" drones: if the ESC burns out, you keep the flight controller.
AIO (all-in-one)
Flight controller and ESC on the same board. Light and compact, ideal for whoops and toothpicks.
Common hole patterns: 30.5 × 30.5 mm (5" and larger), 20 × 20 mm (small drones and some 5") and 25.5 × 25.5 mm (whoops).
Which firmware?
Betaflight
The standard for freestyle, racing and cinematic flying. Very precise flight and a huge community.
INAV
Built for GPS navigation: return to home, position hold and fixed wings. A good choice for long range.
ArduPilot
Autonomous missions and professional use. More complex to configure.
Before you buy, check that the board has an official target in the firmware you want to use.