Flight Controller Firmware Fury

When starting on a new quadcopter build, there are many things that one needs to decide when it comes to components. None might be more important or personal than the choice of flight controller firmware. Although there are several firmware projects available in both open-source and closed-source flavors, three currently stand out among the possibilities.

Betaflight, Butterflight, and FlightOne have made their marks on the drone scene, and I hope what follows will give you the information you need to compare and contrast these projects so that you can make a decision based on what’s best for your needs.

Betaflight

The most popular and widely used firmware right now is Betaflight—an open-source project that was derived from Baseflight and Cleanflight. Although those sound like secret code words used to confuse people, it’s only important to know that Betaflight has been under continual development for more than three years and has grown to be one of the most stable platforms available.

Features such as addressable LED support, DShot motor protocols, black box flight logging, and possibly one of the most robust on-screen displays out there have led Betaflight to be accepted among pilots of many disciplines.

Betaflight was the first to introduce a feature that would flip your aircraft over following a crash. Affectionately called "turtle mode," this has become a must-have among racers who don’t want small mistakes to cost them the entire race.

Additionally, its support for nearly 100 flight controller boards means that you can work with the hardware that best fits your project, and can still have access to the same firmware.

The way you interact with and adjust the settings of your Betaflight firmware is through the Betaflight configurator. Compatible with Windows and OS X systems, the Betaflight configurator is fairly simple to navigate and offers dozens of customizable options for your quadcopter.

Everything from setting up your Universal Asynchronous Receiver/Transmitter (UART) ports (a connection used for communication to specific components), to flight modes, and even proportional integral derivative (PID) controller settings are laid out cleanly on the left. You’ll also find a tab called Command Line Interface (CLI). CLI allows you the ability to code in specific settings without using the graphical user interface.

As the largest of the open-source options out there, Betaflight offers an incredibly large community of users. These people don’t hesitate to offer help with any troubleshooting issues that arise. This is one of the big advantages to using an open-source option. Another big advantage is that updates are frequent and new features are often added.

Butterflight

Butterflight is an open-source fork of Betaflight, developed to focus solely on flight characteristics and to implement specific filters to better handle things such as propwash and gyro interference.

Because it’s a recent derivative, Butterflight supports most of the features that Betaflight users have employed in their latest builds, including on-screen displays, LED strip support, DShot, and black box flight recording.

Additionally, Butterflight natively supports a 32 kHz looptime, which describes how quickly the flight controller can complete a PID loop and improve flight characteristics while in the air. This contributes to its signature "locked-in" feel.

The configurator looks quite similar to Betaflight’s. In fact, it’s the same user interface and can be navigated and used in the same way. Within days of writing this article, a new user interface called Pegasus was released, which tries to combine some of the best parts of the configurators from Betaflight and FlightOne, which is the next firmware on my list.

The Pegasus is still in early public beta testing, so it’s not quite ready for primetime; however, there is much promise in its userinterface design. It should be noted that although Butterflight is compatible with any Betaflight-compatible flight controller, Pegasus is only compatible with Helio Spring flight controllers. These flight controllers were built from the ground up to support Butterflight, and currently offer the best performance.

FlightOne

Formerly called Raceflight, FlightOne is the sole closed-source option on my list. Being closed source, the only flight controllers that can run FlightOne firmware are the Revolt and Millivolt, which are designed and sold by the FlightOne team. However, although you lack choices in the hardware, you gain a tight synergy between hardware and firmware.

The main thing that sets FlightOne apart from its competitors is its use of wizards for its setup process. Upon connecting to the FlightOne configurator, you’re prompted with a series of questions about your setup. Specifics such as receiver type and ESC protocol are requested so that it can set up some of the basic hardware communications.

After that has been completed, you’ll be presented with a few more wizards that will calibrate the flight controller, set up the radio and switches, and make sure the motors are spinning in the right direction. This is all done in a step-by-step method that makes even the most inexperienced pilot feel confident while setting up his or her quad for the first time.

Some other features of the FlightOne firmware include auto launch (which allows the quad to tilt forward and hold position on a racing launch stand), Quopa Mode (similar to Betaflight’s Turtle Mode), numerous flight modes with varying handling and feel, and its own on-screen display.

The claim to fame for FlightOne is the filtering that is done within the firmware, allowing for a smooth flight experience with little-to-no propwash oscillations or gyrometer signal interference. Although it seems that I’m bringing back some of those crazy code words again, I’m really just referring to the things that determine the aircraft’s flight performance.

FlightOne is also the only firmware offering preset PID controller settings and rates. Specifically, some of the presets that are offered actually match the settings flown by some of the most well-known FPV racing and Freestyle pilots, such as Shaun "Nytfury" Taylor and Jonathon "Skitzo" Davis.

Similar to Betaflight, FlightOne also offers a nearly constant stream of updates and feature additions. Its support community on the chat platform, Slack, is a fantastic resource for help and tips on running the firmware. It includes input from the lead developers of the firmware and hardware.

Conclusion

I’ve only broken the surface on these three firmware products, and there is much more detail to each one. It’s important to know what makes each one unique and why you might want to choose it for your setup. There is no right answer and we all have our own preferences, but it’s like Pepsi or Coke, Mac or PC—when it’s all said and done, as long as it gets you flying, that’s what is important.