Elliptical Winged Plane

thingiverse

**SUMMARY:** This aircraft was designed as a high-efficiency slope soaring plane that doesn't require a motor mount due to its intended lightweight construction. A conversion for a motor would be relatively easy to implement if desired. The goal of this design is to reduce the weight of 3D printed aircraft, which can be heavy, by minimizing the amount of material used. The aircraft uses traditional spar and rib techniques and was initially designed to use a V-tail system, but work on that aspect needs completion. A V-tail or balsa wood alternative could be used. The elliptical wing design provides the lowest theoretical induced drag, making it an efficient choice for this plane. However, elliptical wings have poor stall characteristics, stalling the entire wing simultaneously and causing a loss of control and wing drop. This issue can be mitigated with wing tip twist, but that would compromise efficiency. It's essential to avoid stalling the aircraft. Assembly is relatively straightforward, with parts only fitting in one spot. Some components require doubling up, such as fuselage joiners. When printing the second wing, certain parts need mirroring for proper function. The grooves on the ribs are designed for 2mm solid round carbon fiber rods, and hinges for control surfaces are made from 4mm hollow round carbon fiber. **Specs:** * Wingspan: 1.5m * Airfoil: Eppler 193 (http://airfoiltools.com/airfoil/details?airfoil=e193-il) * Weight (Theoretical): 800g * Lift Distribution: Elliptical * Root Chord: 0.2m * Control Surfaces: Flaps, Ailerons, V-tail (or traditional empennage) **Required Materials:** * 2x 6mm hollow box section carbon fiber * 1x 10mm hollow round carbon fiber * 4x 4mm hollow round carbon fiber * 2x 2mm solid round carbon fiber * 6x 9g Servos * Battery and ESC combination The aircraft uses a covering film, but the author has not yet completed this stage of construction. Kraga's tutorial on covering film is recommended for reference. **EDITS:** The design has been modified to include a set angle of incidence for the main wings, which is 5 degrees, chosen based on the max lift-to-drag ratio of the Eppler 193 airfoil. The fuselage has not been printed with this change, so any issues should be reported. Additionally, the wingtip has been redesigned as a solid object to ensure compatibility with various printers. **DISCLAIMER:** The author has not flown this plane yet due to university commitments and may have overlooked potential design flaws. Build at your own risk. The author plans to complete their own aircraft during the next university break and will update the files if necessary.