We’ve written about our design process in detail but we’ve never summarized our design requirements or aircraft mission. This is primarily because Federal Aviation Regulation (FAR) Part 103 is so unregulated. While a transport category aircraft or light-sport aircraft may have specific efficiency, cost, size, etc restrictions put in place either by the FAA or the client, Part 103 lacks such specific limitations. That leads us to our four main design guidelines:
Safety will always be our number one priority. Some safety measures we’ve been following include:
Always leaning on the side of caution rather than efficiency for any design decision where both aren’t possible
Using concrete equations, maths, and physics to support every decision
Independently pursuing the same goal and comparing final answers before implementing either
Checking all designs with industry professionals when possible
When an important design specification isn’t regulated, using the regulations from similar type aircraft as a starting point (eg: Part 23)
Part 103 compliant. Throughout our research and design process, we’ve realized that the vast majority of ultralight airplane designs don’t actually meet Part 103 requirements! Some of them almost comply but some simple math will prove very few actually have a stall speed at or below 24 knots.
Ease of construction and simplicity of design. Like Ludwig Mies van der Rohe who once said “less is more,” we’re strong believers in the elegance of simplicity. If a part can be eliminated, it produces no drag, adds no weight, and can never break.
Appearance. In full honesty, we want to build an airplane that’s both practical as well as good looking. If we just wanted to get in the air, we would have designed a paramotor.
The educational aspect of the design process is also core to our mission. There’s plenty of other ultralight designs, many of which outperform our own, but this whole project was started to learn something new which is a lot cooler in our opinions.
Now that we’ve explained the logic behind our design guidelines, here’s how they manifest themselves numerically. Please note that these values are subject to change. For our latest calculations, please see our Flight Club calculations spreadsheet.
Maximum takeoff weight: 508lb
Pilot weight: 170lb
Empty weight (excluding battery and BRS): 254lb
Stall speed: 24 knots
Cruise speed: 48 knots
Wingspan: 32 feet
Chord: 6 feet
*Editors note: the thought processes and design choices presented in this article don’t necessarily represent those implemented into the final design and are subject to change. Flight Club Aerospace is a group of amateur students with no formal education in any field of engineering. We present this information for educational purposes only, with the understanding that it is not to be re-created without adequate professional oversight and mentorship. For our latest designs and updates, please see our most recent blog posts.