By Oscar Liang at oscarliang.com/
While many FPV drone manufacturers are busy copying each other and releasing near-identical products these days, HGLRC is one of the very few companies still trying to innovate and do something genuinely different. I am genuinely impressed by what HGLRC has achieved with the Rekon35 V2, a 3.5-inch micro FPV drone purpose-built for long-range cruising. It’s clear that a lot of thought went into this design. After flying it and tearing it down, I’ve gathered plenty of thoughts—both good and bad. Here’s my hands-on review.
What’s Included
- 2 sets of propellers (8 in total)
- USB cable for charging
- screws for mounting the props
- screwdriver
- stickers
- manual
Specifications
- Frame: Rekon35 V2
- Flight Controller: HGLRC H743 20A ELRS 2.4G 2S V1 AIO
- FC Firmware: HGLRCH743
- Gyro: ICM42688P
- Motors: Specter 1404 5500KV
- Camera/VTX:
- HD: DJI O4 Lite Air Unit
- Analog: HGLRC Zeus Nano VTX 350mW
- Receiver: Onboard ELRS 2.4G (or 915MHz)
- GPS: HGLRC M100 Mini
- Propellers: Gemfan 3630 triblade
- Supported Battery: 2× 18650 Li-ion cells
- Advertised Weight (without battery)
- HD Version: 180 ±5g
- Analog Version: 174 ±5g
- Power Kit Version: 169 ±5g
- Weight (My Measurements)
- DJI O4 version without batteries: 187.5g
- With 2× Molicel P30B 18650 cells: 278.5g
Design and Build
The HGLRC Rekon35 V2 is a 3.5-inch, 2S FPV drone.
Right away, it stands out thanks to its unique construction. The drone features a fully enclosed injection-molded plastic body that protects all internal electronics, giving it a clean, professional, and durable appearance.
One common issue with the DJI O4 Air Unit is overheating when powered on without airflow. Thankfully, HGLRC addressed this with a large heatsink mounted underneath the air unit. I was able to leave the drone powered on the bench for over 5 minutes without any overheating warnings, which should be even less of a concern during actual flight with constant airflow.
HGLRC also replaced the stock linear-polarized O4 antenna with a longer circularly polarized antenna, improving both range and penetration. Based on my testing, its performance is excellent.
The flight controller and motors are mounted on a carbon fiber plate, with 3mm-thick arms that feel very stiff and robust.
There are two rows of bright RGB LEDs on each side of the drone. Fly this thing at night and it genuinely looks like a tiny UFO gliding through the air. The LEDs are configurable in Betaflight and can be used to display useful information such as GPS status, throttle level, or battery voltage level. Out of the box, they default to a rainbow effect.
Learn about configuring Betaflight LED in this guide: https://oscarliang.com/setup-led-betaflight/
The drone is powered by two 18650 cells housed in a hinged battery compartment (battery is not included). Simply insert the batteries and you’re ready to fly.
Even better, you can leave the batteries inside the drone and charge them directly via the USB-C port on the rear like a DJI Mini, which is incredibly convenient.
The “no exposed wires” design is one of my favorite aspects—everything looks clean, sleek, and well protected.
You can access the DJI O4 Air Unit’s USB port and bind button from the sides of the drone.
To connect the drone to Betaflight, there’s another USB-C port located just below the charging port. You’ll need to push the spring-loaded antenna mount downward to access it.
Battery – It Only Takes 18650!
Open the battery compartment by holding down the two locking tabs and lifting the cover to reveal the battery tray—easily the most interesting aspect of this drone.
The Rekon35 V2 does NOT support LiPo battery. Instead, it runs on two individual 18650 Li-ion cells—yes, the same cylindrical batteries you’d normally use in radios, flashlights, or vaping devices.
At first, this might sound limiting, but it’s actually the core identity of the drone: long-range.
Tear Down: What’s Inside the Drone?
Disassembling the Rekon35 V2 is straightforward. There are only 6 M2 hex screws securing the plastic body to the frame.
The first thing that surprised me was the unconventional flight controller design. It appears HGLRC may have designed this board specifically for the Rekon35 V2—it’s long and rectangular rather than the usual square shape. This is an all-in-one (AIO) board, integrating the ESC and ELRS receiver onto the same PCB. The upside is a very compact layout; the downside is that if any major component fails, you’ll need to replace the entire board.
The GPS module is the HGLRC M100 Mini, which I tested last year and found to be excellent. Despite its tiny size, it uses a u-blox M10 chip, delivering strong performance. I typically get a GPS fix in about 1.5 minutes with 8 satellites, and after 10 minutes it often locks onto 19 satellites.
The camera angle is adjustable, but you’ll need to remove the front canopy to access the mounting screws. Out of the box, the angle is set to around 20 degrees, which is ideal for long-range cruising, so I didn’t feel the need to change it. If you frequently adjust camera angle, you could probably drill a small access hole in the canopy to avoid removing it each time.
The drone also comes with a small physical beeper hidden between the two USB port in the rear, which is pretty loud. If you crash in bushes or tall grass, this will be extremely helpful for recovery.
Flight Performance
https://youtu.be/tmL3qTRXxmI
Smooth, Quiet, and Surprisingly Well Tuned
The first thing I noticed is just how quiet the Rekon35 V2 is. It’s shockingly low-noise for a 3.5-inch drone—you can barely hear it from 100 meters away, even when doing flips and rolls. It’s perfect for discreet cruising.
The second surprise was how stable and smooth it feels in the air. It comes with a fairly aggressive PID and filter tune, which is exactly what I like to see in a BNF. This really shows that HGLRC put genuine effort into tuning rather than shipping a generic setup.
But It’s Not Fast
This is not a freestyle machine; it’s best suited for relaxed cruising.
It hovers at around 30% throttle at takeoff. At first, it feels reasonably agile—you can even do some freestyle moves like flips, rolls, and split-S maneuvers. However, a few minutes into the flight, you can feel the drone slowly losing punch due to voltage sag, and it becomes increasingly risky to attempt aggressive maneuvers as you’re constantly warned about low voltage. That’s the drawback of Li-ion battery: high energy density but low discharge rate.
Top speed is around 70–80 km/h, and cruising typically sits between 40–50 km/h at roughly 40–45% throttle.
Long Flight Time
The advertised 15-minute flight time is fairly accurate for slow cruising. Realistically, you should expect 13–14 minutes if you fly up and down frequently and mix in some freestyle moves here and there, especially with some wind.
In calm conditions with steady cruising, covering 10km or more is absolutely achievable.
Not the Best in Windy Conditions
The Rekon 35 V2 doesn’t handle wind particularly well. In 20mph wind, the quad struggled significantly and was barely moving into headwind.
With LiPo batteries, you could normally just punch through wind, but with Li-ion cells, there is little throttle response due to voltage sag. If you fly too far out in windy conditions, there’s a real risk you may not make it back, so avoid pushing distance when wind is strong.
GPS Rescue Worked Well
GPS Rescue is configured out of the box, and failsafe is set to Rescue mode.
In my testing environment, GPS Rescue worked well and brought the drone back close to the takeoff point.
That said, you should always double-check your Rescue mode settings to ensure they suit your flying environment.
Check out my guide on Rescue Mode: https://oscarliang.com/setup-gps-rescue-mode-betaflight/
Current Sensor Needs Calibration
My Molicel P30B has an actual capacity of around 2851 mAh, but the OSD reported 6036 mAh—more than double the real value. The current sensor scale clearly needs calibration.
Limitations and Potential Improvements
With this quad, battery quality matters a lot. You must use decent 18650 cells—cheap or counterfeit batteries will completely ruin the experience. Unfortunately, fake 18650s are common on eBay and Amazon, which could frustrate beginners who aren’t familiar with sourcing quality cells.
The drone is also slightly heavy for a 3.5-inch quad, weighing 187g without batteries. If your goal is to stay under the 250g weight limit, this may not be the best option out of the box. That said, I already have a few ideas to reduce weight and improve efficiency, and I believe it should be possible to bring it under 250g. I’ll try to cover those modifications in a future post or update this review after the New Year when I have more free time.
Battery Charging
You can charge the batteries inside the drone via USB-C, with a charging power of around 11–12W. This means it takes approximately 2 to 2.5 hours to fully charge two 3000mAh 18650 cells.
Charging appears to stop at around 4.15V per cell, which is actually a good sign—it doesn’t overcharge. However, it doesn’t reach the full 4.20V, so you’re potentially losing a tiny amount of capacity (roughly 50mAh, or about 10 seconds of flight time). In practice, this is negligible.
If you prefer, you can remove the cells and charge them with a dedicated 18650 charger, or even a LiPo charger using a DIY holder like this. These methods are likely to be much faster and ensures a full 4.2V charge. Still, charging directly inside the drone is extremely convenient, perfect for lazy people like me :)
How to Setup
Manual is very helpful.
Firmware
- FC Board: HGLRCH743, comes with BF 4.5.2
- ESC Firmware: Bluejay, 0.21.0 (F-H-40)
- ELRS Receiver: HGLRC Hermes 2.4GHz RX (3.5.3 firmware)
Binding ELRS receiver
Detailed instructions can be found here: https://oscarliang.com/bind-expresslrs-receivers/
Pairing DJI Goggles
Follow the instructions here: https://oscarliang.com/how-to-setup-dji-o4-lite/#Pairing-DJI-Goggles-3-with-O4-Lite. The O4 doesn’t require activation, so you can fly as soon as it’s paired.
Betaflight Setup
- Power & Battery tab: The settings are left at Betaflight default, which are for LiPo batteries, so low-voltage warnings will trigger way too early. For 18650, you should set Minimum Cell Voltage to 3V (depends on the cells you are using, some can safely go as low as 2.8V or even 2.7V). Maximum Cell Voltage to 4.2V. Warning Cell voltage to 3.2V. Current sensor scale also needs changing – I will publish my value on a later date.
- PID Tuning tab: Set up your own rates.
- Modes Tab: Configure your arm switch, angle mode, and turtle mode. For guidance, see this tutorial: https://oscarliang.com/betaflight-modes/#How-to-Setup-Arm-Switch
- Receiver tab: Enable Telemetry
- GPS tab: My usual settings are to enable “Use Galileo” and “Set Home Point Once”, set Ground assistance Type to Auto
- OSD tab: Customize to your preference.
Installing Propellers
Insert the translucent bushings into the prop hubs, mount them on the motors, and secure each prop with two screws.
Important: The Rekon35 V2 uses reversed motor direction.
That’s it—your Rekon35 V2 should now be ready for its maiden flight.
Final Thoughts: Is the HGLRC Rekon35 V2 Worth It?
The HGLRC Rekon35 V2 is a bold experiment—a drone built entirely around 18650 Li-ion. One crucial point is that you must use good-quality cells; poor batteries will result in frustrating performance.
HGLRC clearly invested a lot of effort into the design. This is the most well-thought-out Li-ion-only FPV drone I’ve tested so far. GPS Rescue works well, the quad is efficient, quiet, smooth, and cleverly engineered.
That said, I do wish HGLRC had made the drone lighter, ideally keeping it under the 250g weight limit. Since it’s not designed for freestyle or high-speed flight, the bulky construction feels unnecessary. I believe a large portion of the plastic could be removed to reduce weight.
Even in stock form, a 5 km round trip is entirely possible, which is impressive. Making it lighter would only enhance its potential.
The Rekon35 V2 is not perfect, but it’s genuinely interesting. And in a hobby full of look-alike drones, that alone is refreshing.