Impact of Taper Ratio on Low-Speed, Flat-Winged Glider Flight Performance

Mitansh Dutta

doi:10.58445/rars.4118

##article.authors##

Mitansh Dutta UIUC

DOI:

https://doi.org/10.58445/rars.4118

Keywords:

Low-speed aerodynamics, Flight stability, Experimental aerodynamics

Abstract

While the influence of taper ratio on wing aerodynamics has been studied extensively in

high-speed conditions and theory, its effects on simple, flat wings at low speeds remain less well-characterized, especially in experimental testing. This gap is significant because many small-scale aircraft operate in these low-Reynolds-number conditions. These include gliders, micro air vehicles (MAVs), and hobbyist projects. In this context, low-speed flight refers to flights that operate at approximately 5 m/s, whereas high-speed aircraft operate on the order of hundreds of meters per second. Here, even subtle geometric changes strongly influence flight behavior. Flat wings are important in these applications due to their simplicity, yet their aerodynamic behavior is not well understood through experimentation. Understanding how the taper ratio affects flight in this regime allows us to design efficient low-speed flying vehicles. This study investigates how four taper ratios (0.5, 0.6, 0.8, and 1) in a flat wing impact aerodynamic performance through forty controlled free-flight tests of a balsa-wood glider in an indoor laboratory, where flight distance, horizontal deviation, trajectory, and remaining propeller rotations were measured. Among the tested configurations, moderate taper ratios provided the best balance between aerodynamic efficiency and flight stability for low-speed flat-wing gliders. Thus, these findings provide experimental evidence for the influence of taper ratio on low-Reynolds-number flat-winged gliders' flights. This may help inform the design of small-scale aircraft operating in similar conditions.

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