Introduction
The SpeedyBee F405 AIO flight controller brings a compact yet powerful solution for FPV builds ranging from 2″ cinewhoops to 5″ freestyle quads. In this review, I’ll share my firsthand testing experience—unboxing, setup, and flight performance—while drawing on insights from a professional reviewer’s structure to ensure a comprehensive look at what sets this board apart (and where it could improve).
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Specifications
Flight Controller (FC):
- MCU: STM32F405 (42688P)
- Gyro: ICM-42688P
- Barometer: SPA06-003
- Mounting Holes: 25.5 × 25.5 mm, 2 mm diameter
- Dimensions: 33 × 33 × 8 mm (including heatsinks)
- Weight: 13.9 g (with CNC heatsinks)
- OS: Betaflight (default), INAV (supported)
- OSD: Integrated
- Bluetooth: 2.0 module (for wireless Betaflight configuration)
- USB Port: Onboard USB-C + breakout pad for external access
- Blackbox Flash: 8 MB (internal)
- Input Voltage: 3S–6S LiPo
ESC (4-in-1):
- Continuous Current: 40 A per motor
- Burst Current: 45 A (10 s)
- ESC Firmware: BlueJay JH-40 @48 kHz
- Protocols: DShot300 / DShot600 (others possible, but with caution)
- BEC Outputs: 5 V @ 2 A (shared with 4.5 V) and switchable external BEC (5 V/9 V @ 2 A)
- Input Voltage: 3S–6S LiPo
- Current Sensor: Supported (scale = 254, offset = 0)
Design and Quality
Upon unboxing, the first thing that stands out is the dual-sided aluminum heatsinks—one on each side of the board. These vivid purple heatsinks not only give the SpeedyBee F405 AIO a premium look but also serve two critical purposes:
· Heat Dissipation & Protection:
- The thick aluminum plates help keep both the FC and ESC MOSFETs cooler during sustained high-current flights.
- They offer physical protection, shielding the board from minor impacts and soldering mishaps.
· Aesthetics:
- The signature purple finish differentiates it from more common black- or green-PCB AIOs.
Of course, the trade-off is added thickness and weight. At 8 mm thick and nearly 14 g total, this board is heftier than many competing AIOs. For casual cinewhoops or 5″ builds, that extra 3–4 g isn’t a deal breaker. But for sub-250 g micro builds, it’s worth noting.
Between the heatsinks, the exposed pads are somewhat harder to locate, especially for less experienced builders. Fortunately, the quick-start guide’s annotated pad diagrams are very helpful during soldering.
Weight and Size
Weight: 13.9 g (FC + heatsinks) vs. ~9 g typical for similar AIO boards. The extra mass comes from the robust heatsinks.
Thickness: 8 mm total—consider frame clearance before swapping in this board. Its extra height could conflict with low-profile frames or tightly stacked electronics.
Mounting: Standard 25.5 × 25.5 mm holes mean it fits most 2″-5″ frames. Just verify your canopy’s internal height to accommodate the heatsinks.
In practice, I installed this board on a lightweight 3″ freestyle frame and a 5″ long-range build. It fit perfectly in both, so long as I planned for the extra thickness.
Key Features
Integrated 40 A 4-in-1 ESC
- Pre-flashed with BlueJay JH-40 firmware at 48 kHz, the ESC delivers smooth throttle response and reliable current handling up to 40 A continuous (45 A burst).
- Large, half-millimeter-thick solder pads on M1–M4 simplify motor soldering, even for beginners. However, the corner solder pads are close to the heatsink, so using a fine-tip iron or angling your iron helps avoid bumping the heatsink fins.
Bluetooth Wireless Configuration
- Pair the onboard Bluetooth module with the SpeedyBee smartphone app to configure Betaflight settings wirelessly—no laptop needed.
- Flashing new firmware, adjusting PID gains, and toggling motor rotation can all be done in the field, which is a huge advantage during on-site tuning sessions.
USB-C Extension Pad
- The FC exposes breakout pads for an external USB-C port. In cramped cinewhoop builds, you can wire an external Type-C to a more accessible location on the frame.
- During my test, having the USB-C extension made quick adjustments much less fiddly when the FC was deep inside a carbon tube frame.
Dual BEC Outputs & External BEC Module
- Onboard BEC: 5 V @ 2 A (shared with 4.5 V output) for powering receivers and small peripherals.
- External Switchable BEC: The included module can be soldered to VBAT and give you a 9 V @ 2 A or 5 V @ 2 A output, ideal for powering a DJI O3 Air Unit, O3 Lite, or a high-draw LED strip without overloading the FC’s onboard 5 V regulator.
- This flexibility means you can run modern digital FPV systems without adding extra converters.
ICM-42688P Gyro & Barometer
- The factory SP A0-6003 barometer offers more stable altitude hold in INAV or autonomous GPS modes.
- The ICM-42688P gyro is known for its low noise and accurate readings, benefiting precise flight control and smoother hover.
Onboard OSD & Ample Blackbox Memory
- The integrated OSD displays real-time flight data in analog goggles.
- 8 MB of Blackbox flash allows for dozens of flight logs without an SD card. During tune-ups, this made it easy to capture detailed logs and refine PID settings.
UARTs & Expansion
Four full-function UARTs let you connect ExpressLRS/Crossfire receivers, GPS modules, SmartAudio / IRC Tramp VTX control, and more.
An I2C port is available for external compasses—useful if you eventually want to run INAV or advanced GPS-assisted modes.
Accessories Included
SpeedyBee packages this AIO with several handy add-ons:
- USB-C Extension Board & Cable – Makes USB port access easier in tight builds.
- LED Strip Power Distribution Board – Simplifies soldering multiple WS2812 LED strips by breaking out a single data pad into four pads.
- External BEC Module – Switch between 5 V and 9 V output; connect to VBAT for stable power to VTX or high-draw peripherals.
- Soldering Practice Board – A neat idea for newcomers—practice soldering on a replica pad layout before working on the actual FC.
- Connection Accessories – Heat-shrink tubing, silicone grommets, extra screws, a QR-coded quick-start guide, and a set of vibration-damping spacers.
While none of these are mandatory for basic operation, they streamline setup and add flexibility. For example, I used the LED breakout board to power my 1 m LED strip without worrying about drawing too much current from the FC’s onboard BEC.
Areas for Improvement
Heatsink Access & Soldering Difficulty
The glued-on heatsinks can obstruct several pads (e.g., some UART or motor pads near the edges). Users with thicker soldering irons may find it tricky to reach these pads without special angles or a finer tip.
It would be helpful if SpeedyBee offered a heatsink-free version or allowed easy detachment (e.g., via small screws) for weight-conscious builds.
Weight & Thickness
At nearly 14 g, the SpeedyBee F405 AIO is heavier than many competing boards (~9 g). For cinewhoops or 5″ quads, this extra mass is negligible. However, if you’re targeting sub-250 g micro builds or very tight builds, consider the added weight and 8 mm profile.
INAV Support Clarification
While the specs claim INAV support, I couldn’t find an official INAV target in the current firmware flasher. INAV users may need to wait for a dedicated target or flash via raw BIN files (with added complexity).
Blackbox Logging Options
Although there’s 8 MB internal Flash, there’s no microSD slot. If you record many Blackbox logs in a single session, you might need to offload logs frequently. An SD slot option could benefit heavy tuners.
Flight Performance & Tuning Notes
After mounting the SpeedyBee F405 AIO on a 3″ freestyle quad (500 g all-up weight) and a lightweight 5″ long-range frame (700 g all-up weight), these observations stood out:
- Arming & Throttle Response: Smooth and consistent. No unexpected motor desyncs, thanks to the BlueJay firmware running at 48 kHz.
- PID Tuning: With the ICM-42688P gyro’s low-noise readings, I achieved crisp roll and pitch response in Betaflight. Altitude hold in INAV was more stable than other AIOs I’ve tested.
- ESC Heat: Even after several 3-minute freestyle sessions on 5″ builds, the purple heatsinks stayed relatively cool to the touch. I never saw ESC overheat warnings.
- Connectivity: Using the SpeedyBee app over Bluetooth, I swapped motor rotation and adjusted filter settings mid-session without connecting a laptop—immensely convenient when racing or filming on location.
- Powering a DJI O3 Air Unit: Soldering the external BEC and wiring directly into the DJI O3 was foolproof—no voltage mismatches, and video feed remained stable even under full throttle.
Final Thoughts
The SpeedyBee F405 AIO 40A flight controller offers an outstanding blend of performance, convenience, and build quality for its $55.99 price point. Its standout features—dual-sided heatsinks, reliable 40 A ESC, Bluetooth configuration, and dual BEC outputs—make it a top contender for cinewhoop and 5″ freestyle builds.
Pros:
- Robust dual-sided aluminum heatsinks for excellent cooling and crash protection
- 40 A ESC with BlueJay firmware (48 kHz), delivering smooth motor performance
- Wireless Betaflight configuration via Bluetooth + SpeedyBee app (no laptop needed)
- External USB-C breakout makes in-frame adjustments hassle-free
- Dual 5 V/9 V BEC outputs (onboard + external module) power modern VTXs and accessories
- ICM-42688P gyro and SPA06-003 barometer for stable flight and altitude hold
- Ample accessories (LED breakout, practice board, screws, grommets)
Cons:
- Added thickness (8 mm) and weight (~14 g) due to heatsinks—may not suit ultra-light builds
- Heatsinks glued on, making pad access and troubleshooting trickier
- INAV support is not fully smooth yet (no official target in flasher)
- No microSD slot for external Blackbox logging
If you’re building a cinewhoop or a standard 5″ quad and want a user-friendly, fully featured AIO flight controller, the SpeedyBee F405 AIO is a hard board to beat at this price. Just be mindful of its extra thickness and weight, and prepare your soldering setup (fine-tip iron or angled techniques) to navigate around the heatsink edges. Overall, the F405 AIO strikes a great balance between convenience, reliability, and performance, worthy of any serious FPV pilot’s consideration.
Buy the SpeedyBee F405 AIO 40A now at MEPSKING and take your build to the next level.