I recently got my hands on the FIMI Manta VTOL Fixed-Wing RC Airplane, and I can’t wait to share my experience with you. For those familiar with the RC hobby, you probably already know that a VTOL aircraft offers the best of both worlds: the hover capabilities of a drone and the speed and efficiency of fixed-wing airplane. In this review, we’ll delve into the aircraft’s assembly and setup process, its initial flight performance, and whether this aircraft is for you.
New to fixed wings? Here’s a list of tools which might help you with building and repairing: https://oscarliang.com/fpv-tools/#Tools-for-FPV-Fixed-Wings
What is VTOL?
VTOL stands for “Vertical Take-Off and Landing,” which refers to aircraft that have the unique ability to take off and land vertically, similar to a multirotor, while also having the capability to fly horizontally like a plane.
The FIMI Manta VTOL is equipped with three motors. During takeoff and landing, it operates much like a tricopter, leveraging all three motors. Once it’s airborne and you’re ready to switch to horizontal forward flight, the two front motors tilt forward while the tail motor stops spinning. This transition allows the aircraft to cruise like a twin-motor fixed-wing plane.
The beauty of a VTOL aircraft lies in its versatility. It can take off and land in tight spaces without requiring a runway or manual launch/catch. Moreover, its ability to transition to fixed-wing flight makes it more energy-efficient and better suited for long-range missions than traditional multirotor drones.
Where to Buy?
If you’re in the market for an affordable VTOL, the Manta is the least expensive option available, making it a cost-effective alternative to the Heewing Ranger T1 with VTOL conversion. The build quality isn’t as nice as the T1, but I think the Manta is better value and more fun to fly.
You can get the Fimi Manta VTOL from:
- Banggood: https://oscarliang.com/product-zcbg (Coupon: BG7914ce, Exp 21th Oct)
- AliExpress: https://s.click.aliexpress.com/e/_DEhLP51
You have two options: PNP and PNP+FC. I opted for the PNP+FC version for a smoother build and setup process, as it comes pre-configured on the software side. This feature is particularly beneficial if, like me, you’re new to VTOLs.
The PNP version includes three motors, four servos, and three propellers. The PNP+FC version steps it up by adding an ArduPilot-based flight controller, a 3-in-1 ESC, and a GPS module. Keep in mind that with the PNP+FC version, you’ll still need to supply your own radio receiver, FPV setup, and battery to complete the build.
For ease and convenience, I’d recommend going for the PNP+FC version. I’ll walk you through how I set up mine for its maiden flight.
- Material: Dark EPP Foam
- Wingspan: 700mm
- Length: 445mm
- Motors: 3x 2004 2700KV Brushless Motors (Note: Earlier units might feature 2800KV/3000KV motors)
- Servos: 2x 9g Metal Gear and 2x 9g Plastic Gear
- Propellers: 6026 Two-blade
- ESC: 20A 3-in-1
- Flight Controller (FC): F405 ArduPilot
- GPS: M10
- Compatible Battery: 3S or 4S LiPo or Li-ion (Options include 18650 3S/4S or 21700 3S)
- Supported FPV Systems: Analog, DJI, Walksnail, HDZero
- Supported Radio Systems: SBUS, TBS Crossfire, Tracer, ExpressLRS, and more
- Flight Time: Up to 60 minutes with a 3S 18650 battery, according to FIMI
374g325g, excluding FPV setup, radio receiver, and battery
When you open the box, you’ll find that the plane comes mostly pre-assembled. All the cables are pre-soldered to the components, which saves you a significant amount of time and effort. All the essential hardware, such as wing spars, screws, and connectors, is neatly organized and packed.
Fuselage and Electronics
The electronics, a flight controller (FC) and an ESC, are mounted on a wooden plate in a stack and installed within the fuselage. This stack is friction-fitted, allowing for easy removal if needed, but you might want to consider gluing the stack in place so it doesn’t move around.
Inside the stack, you’ll find an ArduPilot-based F405 flight controller alongside a 3-in-1 ESC.
The battery compartment dimensions, excluding the FC stack, are 120x52x45mm. This space is large enough to accommodate either a 4S 18650 2800mAh battery or a 3S 21700 Li-ion pack.
Here is the side view of the fuselage.
Here’s the connector that connects the wings.
There’s also a GPS module hidden under a glued-on plastic cover. Two unconnected wires are tucked inside the fuselage, presumably for a compass that the GPS module does not have. I do wish the GPS had integrated compass as it’s beneficial for a VTOL but it’s not the end of the world. Anyway, it’s advisable to trim these exposed wires to prevent any electrical shorts.
The under the nose of the fuselage features a removable foam cover, giving you the flexibility to set it up with or without an FPV camera.
The rear motor, crucial for takeoffs and landings, is positioned on the tail. You might notice the motor is canted to one side, rest assured this is normal, it’s to counteract yaw spin from the propeller rotation. However, this design choice dictates that the rear motor must rotate in a specific direction and should not be reversed.
The wings can also be detached effortlessly, thanks to a snap-on design. This feature makes the FIMI Manta highly portable and convenient to transport, especially if you enjoy hiking to various flying sites.
The tilt system’s motor and servos come pre-installed on an aluminium boom.
The build was incredibly straightforward, it took me only 15 minutes. The manual included provides steps on the assembly process.
Assembling the Wings
First, peel off the yellow Kapton tape on the bottom of the wings and foam cover to reveal the channel where the boom will be inserted.
The booms—equipped with the tilt system—are labeled ‘L (Left)’ and ‘R (Right),’ making it easy to match them with the respective wings.
Once inserted, secure the boom with a spar and a small screw.
Gluing Quick Connector
The quick connector needs to be glued into designated recess on the wing. While the kit doesn’t include glue, I used E6000, which gave me excellent results.
Reattaching Channel Panel
After installing the boom, you can now reattach the channel panel. FIMI has thoughtfully pre-applied 3M double-sided foam tape for this (red strips of tape). Simply remove the red backing paper to reveal the adhesive foam pads and press the panel into place.
Installing Servo Linkage
Attach the linkage servo horn to the servo and fasten it securely with the provided screw.
The kit includes nacelles intended to cover the tilt system. However, I found these plastic covers to be somewhat flimsy, and they even interfered with the servo linkage. I chose to remove them, as they seemed more aesthetic than functional. If you wish, you could 3D print sturdier alternatives using PLA or PETG.
Repeat the above process for the other wing, and you’re good to go!
Attaching Wings to Fuselage
This step is as simple as aligning the spar and connector on each wing with the corresponding parts on the fuselage.
Make sure the quick release connector clip in position and it’s not loose otherwise it could pop open during flight.
Finished Build Pictures
The assembled wing weighs in at 325g, not including the battery, FPV setup, or radio receiver.
Setting Up Electronics
For my setup, I used an ExpressLRS receiver (Happymodel EP1 Dual), and Walksnail Avatar VTX/Camera FPV Setup. The Manta VTOL comes with all necessary cables to connect directly to the flight controller.
Here’s the flight controller pinout / connection wiring diagram.
Receiver and Radio Configuration
FIMI conveniently supplies cables for both serial and SBUS receivers. The flight controller comes pre-configured for the CRSF protocol, which means it’s compatible with ExpressLRS, TBS Crossfire, and TBS Tracer out of the box. If you’re using one of these, it’s essentially plug-and-play. For SBUS users, you will need to make some changes in the software, please refer to the manual for detail.
I drilled a couple of holes in the foam, next to the fuselage to secure the RX antennas.
My radio setup with ExpressLRS was a breeze (I’m using the Jumper T20S radio). I created a new model profile specifically for the FIMI Manta VTOL. You’ll need two switches on your radio: one 3-position and one 2-position.
- CH5 is unused
- CH6 for flight mode (Cruise, FWBA, QSTabilize)
- CH7 for RTL (return to home)
- CH8 for switching OSD profile between HD (screen 1) and Analog (screen 2). You don’t really need this if you fly HD.
The other change I made was to invert CH2 (Ele) in the Outputs: Go to Outputs in Model Setup, edit CH2, and in Direction, select INV.
That’s all the radio setup.
If you opt for an Digital FPV system like Walksnail, use the provided 5-pin connector. The VTX power is directly from battery (VBAT), so make sure your VTX supports your battery’s voltage, if not you may consider using a BEC (voltage regulator).
There’s no easy way to mount the video transmitter on this wing, so I 3D-printed a mount for my FPV setup, then gluing it to the nose (it’s also secured by a zip tie where you can’t see it in the picture). It’s definitely not the best solution, but it would do for now. I will try to design a better mount, more specific for this model in the future.
Programming the Flight Controller
ArduPilot may seem intimidating if you’re unfamiliar with it, but I was pleasantly surprised at how simple it was to get the aircraft in the air. Most of the software programming were already done in factory, it’s almost ready to fly out of the box, there’s not much you need to configure.
Anyway, it’s a good idea to double-check the parameters, download ArduPilot Mission Planner here: https://ardupilot.org/planner/docs/mission-planner-installation.html
After connecting the flight controller to your computer via USB, you can verify if your radio link is working, and customize the OSD settings if you want.
To check if the receiver is working, go to the SETUP tab, Mandatory Hardware, Radio Calibration. Here if you move your sticks and switches, you should see movements.
You can configure OSD to your liking, it’s in CONFIG, Onboard OSD. However, unlike Betaflight or iNav where you can configure HD OSD inside their configurators, Ardupilot doesn’t work well with HD FPV system, so you might need to use an online tool (https://notes.stavros.io/ardupilot/hd-osd-tool/) to configure your OSD, save the result as a file then import it into Ardupilot. For analog OSD, the Ardupilot software works just fine and no need for the online tool.
It’s a bit complicated so I just left it at default for my maiden flight which worked fine.
You can also tweak some other settings like flight modes and PID, but you don’t have to if you are unfamiliar with Ardupilot.
For battery, you have choices. The official recommendation is a 3S Li-ion battery, of course you can also use LiPo but Li-ion packs offer longer flight time due to their higher capacity to weight ratio. The specs also suggest the Manta VTOL supports 4S which I am currently using and it seems to work fine. I am using both 4S 1500mah LiPo and 4S 2800mah Li-ion (18650) battery and both fits perfectly, 4S 21700 might be slightly too big for the lip to close.
Get 3S or 4S Li-ion packs here: https://oscarliang.com/li-ion-battery-long-range/#Buying-Ready-Made-Li-ion-Battery-Packs
Installing Propellers and Balancing CG
Last but not least, you’ll need to install the propellers and balance CG (center of gravity). You can find the points of CG, and proper propeller rotations in this diagram.
I found that even with the battery placed all the way back against the FC stack, the aircraft was still nose-heavy. To correct CG, I had to attach 30g of dead weight to the tail.
And there you have it! Your FIMI Manta VTOL should be ready for its maiden flight.
Maiden Flight – How to Operate FIMI Manta VTOL?
How to Arm/Disarm
Arming and disarming the FIMI Manta VTOL is done using the throttle/yaw stick, not switches.
- To arm: throttle down and yaw right, holding for a few seconds. The motors will start spinning.
- To disarm: throttle down and yaw left, holding for a few seconds. The motors will stop spinning.
You don’t need to wait for GPS lock to arm.
Understanding Flight Modes
The Manta offers three flight modes in the stock configuration: QStabilize, FWBA, and Cruise.
- QStabilize: This is for takeoffs and landings. When activated, the front two motors tilt vertically, transforming the aircraft into a multirotor. When armed, all three motors will spin.
- FWBA: This is for forward flight. The front motors tilt horizontally and the rear motor will stop spinning. Only switch to this mode when the plane is 20+ meters off the ground.
- Cruise: Only use this mode if you’ve set waypoints; otherwise, avoid it. In this mode the plane doesn’t respond to user elevon command.
Before taking off, a few checks are in order:
- Control Test: Do a “High Five” test in FWBA mode to ensure control surfaces are working correctly (see below picture for demonstration).
- Hover Test: You can perform a hover test at home by setting the aircraft to QStabilize, arming it, and hovering it like an FPV drone. It might feel a bit wobbly and not be as stable as a typical multirotor but that’s normal.
- GPS Lock: Before take-off, make sure the GPS has locked on, indicated by a rapidly blinking blue LED on the flight controller. If it’s not locked, the return-to-home (RTL) feature won’t work. You can still arm and fly without GPS lock.
Takeoff and Switching to Forward Flight
Begin by taking off in QStabilize mode and ascend 20 meters or higher before switching to FWBA for forward flight. If you get a ‘Transition Failed’ warning on the OSD, it could be a false alarm, i normally just ignore it.
For landing, get to where you plan to land, slow down and switch back to QStabilize mode, then descend gradually.
The FIMI Manta is impressively stable in both hover and forward flight modes. You can slow down or speed up without any dramatic shifts in behavior, which is great for both beginners and advanced pilots.
Flight Performance and Characteristics
The Manta’s small form factor does make it susceptible to windy conditions. In windy condition (15+ MPH) it could be a bit wobbly. If you know how to fine tune PID you might be able to improve wind handling.
I am getting about 30 mins of flight time with a 4S 2800mAh Li-ion pack going at 50km/h (31MPH), it’s far from the advertised 60 minutes flight time. Using the same battery I could get over 40 mins of flight time on my T1 Ranger (without VTOL conversion). The FIMI Manta is definitely not as efficient as the the T1, but overall I am still quite happy with the flight time considering it’s a fixed wing, and it’s got the extra weight of the VTOL system.
I noticed that the aircraft tends to climb / pitch up at high throttle (over 50%), requiring constant manual Elevon adjustments to maintain level flight. Lowering the throttle back to around 40% helped level it out. To fix this, you could either adjust the trim, board alignment in the software or modify the front motor servo endpoints to change the down thrust angle.
GPS and Current Sensors
The Manta uses an M10 GPS module, which, surprisingly, took over 3 minutes to get a GPS lock (sometimes 5 minutes), but I do get a maximum of 14+ satellites at one point so it’s not bad. Its performance is comparable to an unoptimized BN220 and falls short of other M10 modules I’ve tested. Additionally, the current sensor measurement seemed off, reading about 30-50% lower which I think could be a calibration issue.
Potential Software Tweaks
Fimi has done a solid job with the basic software setup, but there’s room for improvement. For example, the front motors continue to spin during zero throttle glides. Enabling the ESC brake could reduce drag and enhance low-throttle performance.
Unstable Landing at Low Voltage
If you are using Li-ion battery, make sure not to land too late. When switching to QStbalize mode, as all 3 motors are spinning at a decent speed to hover, it results in a pretty bad voltage sag, and when voltage gets too low, the plane might struggle to stabilize and wobble more than it should, it could even flip over when it’s windy. It’s less of a problem with LiPo battery as they can normally supply higher current.
The FIMI Manta VTOL is a game-changer in the world of long range FPV VTOL aircraft. With its almost Plug-and-Play setup, integrated ArduPilot software, and solid build, it’s an appealing choice for both newcomers and experienced pilots who want to get into VTOL.
You can get the Fimi Manta VTOL from:
- Banggood: https://oscarliang.com/product-zcbg (Coupon: BG7914ce, Exp 21th Oct)
- AliExpress: https://s.click.aliexpress.com/e/_DEhLP51
- Design: The wing-style aircraft design is sleek and eye-catching.
- Price: Priced as low as £110, it’s one of the cheapest VTOL you can get today.
- Components: Decent quality parts and pre-installed electronics offer excellent value.
- Build Quality: Constructed from durable black EPP foam. Overall kit quality isn’t as good as the Heewing T1 Ranger, but for the price it’s excellent value.
- Flight Time: Impressive endurance, over 30mins with 4S 18650.
- Software: Most factory settings are programmed out of the box, saving users’ time.
- GPS Performance: Generally reliable, but taking a long time for the initial lock.
- Lack of Compass: The absence of a compass in the GPS module isn’t a deal-breaker but could improve navigation.
- Quick Connectors: They’re glued on, not screwed—making them less secure than some might prefer.
- VTX Mounting: There’s no easy way to mount VTX, a clean setup requires a 3D-printed mount.
- Detachable Wings: Convenient for portability but the mechanism could be made more secure. Gluing the wings to the fuselage is an option but reduces portability.
- Flimsy Nacelle Covers: These plastic covers are subpar and can obstruct servo movement.
- Weight Distribution: The aircraft becomes front-heavy with an FPV setup, requiring additional tail weight, which isn’t ideal for efficiency.
- Wind resistance: A bit wobbly in windy condition.
Is the FIMI Manta VTOL for You?
If you’re interested in a hybrid multi-rotor plane, the FIMI Manta VTOL is worth your consideration. It offers stable flight, user-friendly controls, and a smooth transition between hovering and forward flight.
For those looking to dive into the world of VTOL aircraft without breaking the bank, the FIMI Manta stands out as a well-rounded choice and it’s fun to fly. Despite some minor drawbacks, its overall performance and factory programming make it a worthwhile investment.