Are you considering building a tricopter for your next FPV drone project? You might want to hit pause on that thought. As you just heard in the video above, when it comes to modern FPV flight, there’s a strong consensus among experts like Joshua Bardwell: tricopters simply don’t make the cut anymore. But why such a definitive stance? Let’s dive deeper into the history, technology, and practical reasons why quadcopters have far surpassed their three-propeller counterparts.
The Evolution of Yaw Control: Why ESC Braking Changed Everything
To understand why tricopters fell out of favor, we first need to look at a crucial technological advancement: ESCs (Electronic Speed Controllers) with braking, often referred to as ‘damped light’ mode. Back in the day, say six or seven years ago, ESCs didn’t have the ability to actively slow a motor down. When you wanted a prop to decelerate, it relied purely on drag, meaning the motor would just coast to a stop. This resulted in very slow deceleration, which was a huge problem for yaw performance.
Imagine if you were driving a car and the only way to slow down was to take your foot off the gas and wait for friction to do its job. Turning corners quickly and precisely would be nearly impossible! The same principle applied to early multirotors.
How ESC Braking Revolutionized Flight
Modern ESCs, equipped with braking (or damped light), use the motor’s own coils to actively generate a braking force. This means the ESC can precisely and rapidly slow down a motor, significantly improving how quickly and accurately a drone can change its yaw (rotational movement around its vertical axis). This rapid deceleration is key for responsive flight characteristics, especially in FPV flying where quick, precise maneuvers are essential.
With this advancement, quadcopters gained superior yaw performance. They could now make sharp, stable turns by precisely varying the speed of their four motors. This eliminated the primary reason tricopters were ever considered superior.
The Fundamental Flaws of Tricopter Design
Before ESC braking, if you wanted a multirotor with good yaw performance, the common solution was to put one of the rear motors on a servo, allowing it to tilt back and forth. This tilting mechanism provided the “swooshiness,” as David Windestål (a legendary figure in tricopter development) used to call it. However, this design introduced several inherent problems that modern technology has made obsolete.
Precision and Responsiveness Issues with Servos
Servos, while useful in many RC applications, are mechanical components. They have inherent limitations in terms of speed, precision, and durability compared to the direct electronic control of modern ESCs. For fine-tuned yaw control, a servo simply isn’t precise enough to fight the powerful gyroscopic forces generated by a spinning propeller.
Imagine a large bicycle wheel, spinning rapidly. If you try to twist it, you’ll feel a strong resistance – that’s the gyroscopic effect. A tricopter’s servo has to constantly fight this force to tilt the motor, and it’s simply not as responsive or accurate as varying motor speeds electronically.
Durability and Reliability Concerns
Furthermore, servos are fragile components. In the inevitable event of a crash (and crashes are a part of FPV), that exposed servo is highly susceptible to damage. This means more frequent repairs and replacements, adding to the cost and downtime of your drone.
The “Idle Throttle” Dilemma
Another significant drawback of servo-based yaw is what happens at idle throttle. If you lower the throttle significantly, the prop is spinning slower, reducing the gyroscopic effect that the servo relies on for control. This can lead to very poor or even non-existent yaw authority, making the drone unstable and difficult to control, especially during descent or low-power maneuvers.
The Bardwell Argument: Even the Pioneers Gave Up
Perhaps the most compelling argument against building a tricopter today comes from the very people who championed them. David Windestål, the “foremost proponent of tricopters in the world,” actually invented his own specific flight controller and even a fork of flight control software called TriFlight. He dedicated significant effort to perfecting the tricopter design.
Yet, as Joshua Bardwell highlights, even Windestål eventually gave up, concluding they weren’t worth the effort. He reportedly found that even the “best tricopters were bad multirotors.” This historical evidence from a pioneer who pushed the boundaries of tricopter design speaks volumes: if the person who literally invented specialized hardware and software for them moved on, so should most modern builders.
Modern Quadcopters: The Superior Choice
Today’s quadcopters offer unparalleled performance, reliability, and ease of building thanks to advances in ESC technology, flight controller algorithms (like those in Betaflight), and robust component designs. Their symmetrical layout and the absence of mechanical yaw mechanisms mean:
- Superior Yaw Performance: Instantaneous and precise yaw control thanks to ESC braking.
- Increased Durability: Fewer moving parts (no exposed yaw servo) mean a more robust frame, especially important in FPV where crashes are common.
- Simpler Configuration: Standard quadcopter mixers are readily available and well-supported in flight control software, unlike the “weird mixer” configurations for tricopters.
- Wider Component Availability: The vast majority of FPV components (frames, motors, ESCs, flight controllers) are designed and optimized for quadcopters, offering builders more choice and better value.
Imagine trying to find replacement parts or troubleshooting guides for a niche, outdated drone design versus a ubiquitous quadcopter. The difference in support and community knowledge is immense.
Who Should Still Build a Tricopter?
So, is there *any* reason to build a tricopter today? According to Bardwell, only if you’re “a glutton for punishment or a historical recreationist.”
- If you enjoy the challenge of working with outdated technology.
- If you are passionate about the history of FPV and want to experience how things were “back then.”
- If you appreciate the unique aesthetics of a three-motor setup and don’t prioritize modern flight performance.
However, if your goal is to build a reliable, high-performance FPV drone that flies well and is easy to maintain, configuring a tricopter with modern hardware for anything other than a historical project is generally not recommended.
Defying Bardwell: Your FPV Tricopter Questions
What is a tricopter?
A tricopter is a type of drone or multirotor aircraft that has three propellers. It’s an older design compared to quadcopters, which have four propellers.
Why are tricopters generally not recommended for modern FPV flying?
Tricopters are not recommended because advancements like ESC braking in quadcopters provide much better and more reliable control, making quadcopters superior for modern FPV flight.
What is ‘ESC braking’ and why is it important for drone performance?
ESC braking allows a drone’s motors to slow down very quickly and precisely. This significantly improves how fast and accurately a drone can turn (yaw), making flight more responsive.
What were the main disadvantages of tricopter design?
Tricopters relied on a mechanical servo for yaw control, which was less precise, slower, and more fragile than electronic motor control. This design also led to instability at lower throttle settings.
