Minion2 Endurance Wing
Larger wing, carbon-fiber fuselage, and propulsion upgrade.
Overview
Tasked with evolving the Minion fixed-wing UAV into a more capable remote-sensing platform, I led a comprehensive redesign focused on extending endurance and improving survivability during belling landings. Using lifting-line-based software that I wrote, developed a higher-aspect-ratio wing that maintained the same chord but delivered significantly lower induced drag. To support this longer wing, I designed a spar-less composite wing structure. Early prototypes failed as when the top wing surface buckled but we iterated on the structural design and eventually ended up with a lightweight and robust wing that could survive the rough belling landings.
Additionally, I redesigned the fuselage structure with integrated carbon longeron stiffeners, enabling the airframe be lighter and to more reliably withstand repeated belly landings on rough terrain. I also led the re-sizing of the entire propulsion system, changing out the motor, propeller, and battery to optimize it for the new wing geometry and cruising speed. The combined upgrades yielded a validated 40% increase in endurance, transforming Minion2 into the primary platform used for remote-sensing research at Utah State for several years.
Production version of the Minion2.
Internal wing structure. The compression member and reinforced joiner can be seen.
Close up on the wing joiner that transfers loads to the wing skin and commpreesion member.
Failed compression member. This wing was repaired and reused. The final design fixed this design flaw.
Two prototype wings ready for flight testing.
Updated fuselage structure with carbon longerons.
The longerons can be seen here at the bottom of the payload bay. There is one in each corner of the fuselage.
The wing team!
Accomplishments
- ✓Increased flight endurance by ~40% through higher-aspect-ratio wing, efficient composite structure, and propulsion optimization.
- ✓Pioneered lightweight, high-strength spar-less wing with custom carbon joiner.
- ✓Reinforced carbon fuselage internally for belly-landing durability without changing outer mold line or adding mass.
- ✓Matched motor, propeller, and battery upgrades to new aero and structural efficiencies while preserving handling qualities.
Lessons Learned
- •Spar-less composite wings demand precise load-path design and rigorous proof-testing; early failures were invaluable for final robustness.
- •Endurance gains are multiplicative. Small improvements in airframe, wing, and propulsion efficiency compound dramatically.