I am very excited and scared at the same time with this project. I will be building a fixed wing and attempt to fly it in FPV. I have absolutely no idea and experience with wings so I am expecting some explosion and blood in this one :)
Many thanks to Flybot for trusting a noob and providing me with the Mini Race Wing. You can find out more about this product or purchase it on their website: http://flybot.de/en/miniracewing-kit-fpv-race-wing
What’s Special about the Mini Race Wing?
- It uses carbon fibre frame, and the body builds/looks just like a mini quad!
- Normally a wing is just a whole piece of foam, what Flybot did here is very clever with the detachable wings. It minimizes the impact in a crash and it’s easier for transportation too
- The Mini Race Wing is really fast :)
Unboxing & My Setup
The wing comes with everything you need except the electronics, and all the parts are nicely packaged. The wings are made of foam, the elevons are made of balso wood, and the frame is carbon fibre.
I am new to fixed wings, but I was told many mini quad motor and ESC should work fine with this wing. On Flybot’s website they suggest a few different motor/ESC/Battery setup that gives you different top speeds, so that’s an useful guideline for what kind of speed you can expect from your own setup.
For the motor, I believe anything between 2205 to 2207 2300KV to 2600KV should work fine. I decided to use Sunnysky R2306 2600KV just because I have a spare laying around. To pair with this motor I am using 5045 two-blade propeller. I found this setup to be relatively efficient and doesn’t draw more than 25A of current during flight.
For the ESC, it needs to meet the current requirement of the motor and prop combination, and it also needs to have built-in 5V BEC to power your servos and RX. Old ESC should be fine, all those fancy stuff like “active-braking” or “hardware PWM” etc don’t mean much to a wing :) I will be using a 4-year-old Hobbyking 30A ESC.
For receiver, you should use one with at least 3 PWM channels (throttle, elevator, aileron). SBUS or PPM are not useful in this case unless you are using a flight controller with it. D4R-II would be an ideal choice for the job.
- Motor: Sunnysky R2306 2600KV
- Propeller: 5045×2
- ESC: HobbyKing 30A ESC
- Servo: 9g Servo x2 (blue, cheap ones on ebay)
- Receiver: Frsky D4R-II
- Battery: 4S 1500mAh
- Runcam Swift 2 (the VBAT OSD would be extremely useful here)
- some random VTX that supports 4S LiPo
For assembly you will also need these tools:
- Super Glue
- Scotch Tape (5cm+ wide)
Building Mini Race Wing
So I started putting this wing together by following Flybot’s official manual. The manual is quite simple and I wish they could’ve included more images, or even a build instruction video. As a complete wing beginner, I found myself taking a long time just trying to figure out what the instructions mean. However I don’t think it would be a problem for those who has already built a RC plane before.
Here I super-glued the carbon rods to the wings for better rigidity and strength, and cut the slots in the elevons to insert the rudder horns later.
Then attached the elevons to the wing using scotch tapes.
Here I started working on the servo linkage. I was asked to cut these metal rods to a certain length, which wasn’t easy to do without the right tools. For me I had to use a file to make a small cut then snap it by hand.
Quite a few things in this wing rely on user DIY, which I think can totally be done by manufacturer before the product is shipped. For example, this rods cutting, and the elevon slots. I asked Flybot about this and hopefully they can make it a bit more user friendly in the future.
To make sure the length of the linkage is right, I tried it with the servo first before they were glued in the wings.
I realized the servo wires weren’t long enough, so extension was required. I think the wires should be around 27cm-29cm long excluding the connector. Once that’s done, I hot-glued the servos in place.
And finally put the MINI RACE WING decal stickers on and I had successfully assembled the wings.
Electronics Connection and Install
The connection is relatively simple, your battery powers the ESC, which then controls the motor. The ESC powers the receiver (RX), but receives signal from the RX’s throttle channel, while the servos are connected to and powered by the RX.
Here I soldered the motor and ESC together. Note that if you cannot change motor rotation in the ESC, you can do that by swapping two of the motor wires. Motor rotation is important because it determines which props you should use (CW or CCW).
The FPV system is a separate branch in the connection diagram. I prefer using gears that can be powered directly from battery to avoid using voltage regulators.
To power my VTX and FPV Camera, I decided use a balance lead connector with an LC filter in between (to reduce voltage spikes and noise). Of course you could also just share power from the ESC to avoid the additional connector, but I like having the option to leave my FPV gear turned off if I just want to fly LOS.
And here is how the main body looks like when I put everything together.
The Mini Race Wing builds and looks just like a mini quad. That’s what makes it so special IMO. :)
The wings are attached to the “wing mounts” (Carbon Rod Holders) at the bottom, and the servos are connected to the radio receiver with these extension leads. So in a crash, the wings can be detached and the servos can get disconnected from the main body to minimize the impact.
A closer look at the wing mount.
I mounted the wings, and marked where the COG is.
Setting up Taranis
Flights and thoughts
I have been quite busy lately so I haven’t had much time for flying. This is my first wing ever so I am still learning how to fly it properly. So far it’s been very challenging since I am not cheating using a flight controller (I’ve heard iNav’s autolaunch makes everything much easier) :) It took me a good afternoon and about 30 crashes just to learn how to launch it. But so far it’s been very rewarding and this wing has been really tough and holding up to abuses from a noob :)
I do plan to install a FC in this wing and see what differences it makes in the near future, stay tuned :)