Listed on RCGroups with numerous photos.
Skywalker 1880 Quadplane VTOL wings
For use with APM Quadplane.
I built these so I could swap out my Skywalker’s wings when I needed VTOL capability. I spent a long time researching and planning this design. This was a very time consuming project.
- I used Sunnysky X2216-8 KV: 1250 motors with APC 10x4.5 propellers. The high KV is designed to output high power for a short period of time. I only need about 15 seconds for takeoff and 45 seconds for landing. I don’t want to drag larger props through the air when in cruise flight. With a pair of 1400mAh batteries on the wings I could get about 3 mins of hover.
- The props face down to minimize turbulence over the top of the wing in cruise flight. They also keep the booms out of the high pressure thrust.
- Carbon fiber plates keep the quad stiff to reduce bending.
- Small high C 4s battery attached to each wing. This allows me to use Li-ion batteries in the fuselage for maximum endurance. I can land with the Li-ion pack nearly totally depleted without concern about not having enough thrust to do a go-around.
- The wing batteries are interconnected to keep their voltage balanced. In case of a failure of one battery, you should still be able to land safely (inadvertently tested!)
- Booms are detachable with a set screw for easy transport and repair. The servo connectors run inside the tube and the power runs through XT30 connectors.
 - Motor mounts have a forward angle so the propellers do not create a rearward thrust vector at high angle of attack.
- Cabling built for Pixhawk. Including cable to measure voltage and current of quad system for transmission through telemetry and OSD.
Using a 4S3P 18650 pack (10,500 mAh) I could fly for about 40 minutes. The quad wings cost about 20% efficiency compared to the regular wings. I would also have to land with more voltage on the Li-ion pack when I didn’t have the quad wings to perform the landing.
The quad wings weigh 675g more than the standard wings, and with the wing batteries it adds about 1000g. Hover at 3.4 kg at 28 amps per wing (388 watts) with 600g Li-ion pack and two 1800mAh 4s wing batteries. Adding a 400g Sony camera hover increases to 36 amps (480 watts). This was too heavy, but I could still fly it.
Take offs are very easy, I only need to climb about 3 meters into the air before I switch to FBW and start the horizontal takeoff “roll”. Once the wings are creating lift the quad motors will wind down and come to a stop after 5 seconds of reaching cruise speed. The landing is usually a constant descent with the occasional momentary hover, so it uses much less power.
I can send you my parameters to get you going.
I’ll ship it via FedEx anywhere in the US for only $30.
If you need a new Skywalker kit I have an extra to sell.
Here is a takeoff. The big yaw was caused by the APM weather vane function. It is not necessary to climb this high. https://youtu.be/f81n0aXdvKc
Here is a rapid takeoff, where I should have climbed up a bit more. https://youtu.be/cttLu3L6x4o
Here is a landing