Introduction

It’s time for another airplane project. Stork is an aircraft in a classic layout with a push propeller and
V-Tail. The main objectives were the simplicity of the constuction, and the combination of compactness and great performance. Aircraft is suitable for long-range flights as well as for calm LOS flying. Airframe is printed mainly from LW-PLA with additions from regular PLA or other hard material. For the prototype, I decided to cut some parts with laser from plywood.

Stork in Store

I invite you to visit the product page where you can get your files and build your own Stork.

General Data

• Wingspan: 1600mm
• Lenght: 950mm
• Wing area: 24 dm^2
• AUW: 1500g (max 3000g)
• Optimal Cruise Speed: 50-60 km/h
  

Visualization

CFD

Below are some graphs from the CFD studies. The results are very favorable. Zero Cm torque is practically at zero angle of attack. Lateral stability is provided by a large margin. CL/CD ratio is very good, and the optimal cruising speed is within 50-60 km/h. This should allow efficient, long cruising.

Efficiency

During flight tests, I left it in the loiter for a long time. I got a result of 1.21 Wh/km which I think is good result. You can expect an even better performance in cruise on a straight line. As you can see, an average of just over 30% throttle was needed for stable flight.

Build

I described the construction process step by step in the assembly instructions using graphics. You can check it out here: USER MANUAL

Required accessories:

Reccomended elecronics:

• Motor: 2830 1200KV Propdrive / 4108 620KV / 2814 900KV
• Propeller: 10×5 / 12×10 / 13×6.5
• ESC 40A
• Baterry: 4S Lipo or Lion from 3000 mAh to 21000 mAh
• Servos: 4x Corona 929MG Metal Gear or similar Micro Servos.
• Any Flight Controller (The prototype used a Pixhawk)

Printing Settings:

LW-PLA Airframe, several parts from hard material like PLA or PET-G

• layer height: 0,25 mm
• single wall 0,4mm thickness
• 3% Gyroid infill.
• Temperature: 235 degrees,
• flow 60%
• fan speed: 0%

Some photos and info about the construction

In the end, I decided not to make dedicated mounts for cameras, vtx, antennas, etc. Due to the fact that everyone uses something different I decided to make a fully detachable nose and adapt it for standard FPV cameras. In addition, in the file package I provide a files of the nose, all hatches, the rear part of the fuselage with motor mounts and the wing with servo mounts in parasolid format. If you want to adjust it to your needs (custom equipment, mounts, antenna slot etc.) then you are able to do it in an easy way with these files.

I cut some extras out of plywood. These parts are printed by default from PLA or other hard material.

Initially I had the fuselage in a shorter version. However, after the first flight, I decided to redesign it and make it longer. This was due to the difficulty of proper balancing with a small battery and the lack of a camera at the front.

I also made the wings out of foam. I cut them out using a thermal plotter, which I described here:

CNC HOTWIRE CUTTER DESIGN

I also made printed wings, of course, and such are available in the file package. If anyone would like to cut them out of foam I can provide the wing plan and wing root and tip in dxf format.

So I have 2 sets of wings, but I finished the project with the printed ones because I wanted to be sure to get everything right with the print files. The foam ones still need some work to finish.
Wngs are fully removable and their installation is done with plastic screws. This method is very simple and robust. Screws are secured with nuts from the inside of the fuselage. Reinforced wing root and inside of fuselage makes that the airframe will be intact even if the wings are frequently detached. You can also see it in the video below.

There are also more photos and videos of the process of building the Stork and other models on Instagram.

This is what the finished first version looked like.

And this is what the target version with extended fuselage looks

First Flights

It was time for the first flights. The plane in its light version, with Runcam 2 camera, 4s 3700mah battery, and Pixhawk weighed only 1600g. It can hold much more, but I do not recommend exceeding 3000g. The flights took place as expected. The aircraft is very stable and can forgive a lot. When the center of gravity is properly set (and it is 65mm from the leading edge) the plane does not require any trimming and the flight is easy even in full manual mode. I tested it with a flight controller as well as without and in both cases it performs great. You can feel as if you are flying a slightly more agile motor glider. Plane also performs very well in strong winds. Stork is very suitable as an FPV platform, but you can also fly it LOS without any problems.

Here’s a bit of footage from the flight

Summary

I encourage you to purchase the print files and build your own Stork. I would be happy to receive feedback and any suggestions from you. Perhaps this is not the end of the development of this design. and add-ons or another development version will be created for it. Perhaps there will be another developmental version of this aircraft and some additions. I’m sure I’ll record more videos of Stork flights. I will add them to this article. However, most often you can meet such activity on Instagram and Tech Group on Facebook, to which I cordially invite you.

FLIGHTORY TECH GROUP