FPV Drone Glossary
Essential Terms Every Pilot Should Know
Why a Glossary Matters in FPV
The world of FPV drones is packed with unique terms, abbreviations, and technical jargon. If you’re new, it can feel overwhelming — especially when forums and videos are full of acronyms like “ELRS,” “BLHeli_32,” or “C-rating.”
This FPV Drone Glossary is your go-to reference. You’ll find clear explanations for the terms that matter most. For a step-by-step path to your first flight, read our FPV Drone Beginner Guide.
Flight Modes & Control
- Acro Mode (Manual / Rate Mode): Full manual control with no self-levelling. Stick position controls the rate of rotation directly. Essential for freestyle and racing. See also: Acro Trainer in Betaflight for beginners.
- Angle Mode: Self-levelling flight mode where stick input changes tilt angle. Best for basic stability.
- Horizon Mode: A hybrid mode — self-levels at small stick inputs but allows flips/rolls at full deflection.
- Throttle: Controls altitude by increasing or decreasing motor speed.
- Pitch (Elevator): Tilts the drone forward/backward for forward/reverse motion.
- Roll (Aileron): Tilts the drone left/right for sideways movement.
- Yaw (Rudder): Rotates the drone clockwise or counter-clockwise around its vertical axis.
Flight Controller & Firmware
- Flight Controller (FC): The drone’s “brain,” processing pilot commands and sensor data to control the motors.
- Betaflight: Open-source firmware popular for freestyle and racing drones, offering extensive tuning and GPS rescue mode.
- Betaflight Configurator: PC software for configuring Betaflight flight controllers via USB.
- KISS: Closed-source firmware with a smooth flight feel, requires KISS-specific hardware.
- iNAV: Open-source firmware focused on long-range and autonomous flight.
- CLI Tab: Command-line interface in Betaflight Configurator for advanced settings.
- Ports Tab: Configures UART connections for receivers and peripherals.
- Channel Map: Assigns stick movements to correct control channels.
- PID Tuning: Adjusting Proportional, Integral, and Derivative values to refine flight handling. Often aided by Blackbox logs.
- Blackbox: Onboard data logging tool for reviewing and tuning flight performance.
Motor & ESC Systems
- ESC (Electronic Speed Controller): Regulates motor speed based on FC commands.
- ESC Protocol: Communication method between FC and ESC (e.g., DShot, Multishot).
- BLHeli_S / BLHeli_32: ESC firmware; BLHeli_32 offers more advanced features.
- DShot Speed: Digital signal speed for ESC control (e.g., DShot300, DShot600).
- Motor Output Limit: Caps maximum motor power for training or tuning.
Video & FPV Systems
- FPV (First Person View): Flying via a live camera feed from the drone.
- Analog FPV System: Low resolution but ultra-low latency and lightweight; prone to static interference.
- Digital FPV System: High-definition feed (720p–1080p) with systems like DJI, Walksnail, HDZero.
- VTX (Video Transmitter): Sends the drone camera feed to the goggles.
- VRX (Video Receiver): Receives video feed from the VTX.
- Antennas: Transmit and receive video signals; design impacts range and clarity.
- DVR (Digital Video Recorder): Records FPV feed for review or crash location.
- OSD (On-Screen Display): Shows flight data (battery voltage, RSSI) over video feed.
- OFDM: Digital modulation used in DJI/Walksnail for stable HD video.
Radio Control Systems
- TX (Transmitter): The handheld controller used by the pilot.
- RX (Receiver): Mounted on the drone to receive control signals.
- ExpressLRS (ELRS): Open-source, ultra-low latency long-range radio link.
- Crossfire: TBS long-range radio system, reliable for extreme distances.
- Latency: Delay between pilot input and drone response; low latency is critical in FPV.
GPS & Navigation
- GPS Rescue / Return-to-Home (RTH): Uses GPS to bring the drone back after signal loss or low battery.
- Long-Range FPV Drone: Built for distance flights with efficient motors and large batteries.
- MAVLink: Telemetry/control protocol.
- VLOS (Visual Line of Sight): Drone is always visible without FPV.
- EVLOS (Extended VLOS): Beyond normal sight but aided by a spotter.
- BVLOS (Beyond VLOS): Completely beyond sight; regulated in most countries.
Drone Types & Sizes
- Tiny Whoop: 65–85mm ducted prop quads, safe for indoor flight.
- Toothpick: Ultra-light quads prioritising agility.
- Cinewhoop: Small prop-guard drones for stable cinematic footage.
- Freestyle: 5-inch quads built for tricks and flow.
- Racing Drone: Optimised for speed and gate navigation.
- Long-Range: 6–7 inch builds designed for distance.
- Quadcopter (Quad): Multirotor with four propellers.
Batteries & Power
- LiPo (Lithium Polymer): Standard FPV battery type; lightweight and high-discharge.
- LiHV (High Voltage LiPo): Can charge to 4.35V per cell for extra performance.
- Li-Ion (Lithium-Ion): Higher capacity for long range, but lower discharge.
- S-Rating: Number of cells (e.g., 4S ≈ 14.8V).
- C-Rating: Discharge rate capacity.
- Voltage Sag: Drop in voltage under load.
- mAh (Milliamp-Hours): Battery capacity; higher means longer flight but heavier.
- Watt-Hour (Wh): Capacity measure used for airline travel limits.
Miscellaneous & Safety
- Gimbal (Transmitter): Control sticks on a radio; also refers to camera stabilisers.
- Failsafe: Pre-programmed response for signal loss.
- Flip Over After Crash: Betaflight feature to self-right the drone.
- Propellers: Blades producing lift; size/pitch impacts performance.
- Spotter: Visual observer for safety and legal compliance.
- Tuning: Adjusting flight controller settings for stability and performance.
- ViFly Finder: Beeper to help locate a crashed drone.
- RPA / RPAS: Regulatory terms for drones and their systems.
- RePL / ReOC: Australian commercial pilot and operator licences.
How to Use This Glossary
If you’re just starting, focus on terms in Flight Modes & Control and Video & FPV Systems first — they’ll help you understand the basics. As you progress, refer to Batteries & Power and Tuning terms to optimise performance.
Next step: Learn how to put these terms into action in our FPV Drone Beginner Guide or explore how FPV is shaping creative industries in The Growing Role of FPV Drone Pilots in Cinematic Videography.
