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Aerodynamic Evaluation of NACA 6-Series Airfoils for High-Altitude Glider Applications

##article.authors##

  • Shaswat Srivastava Polygence

DOI:

https://doi.org/10.58445/rars.3294

Keywords:

High-altitude gliders, Airfoil performance, Aerodynamic efficiency

Abstract

High-altitude gliders face the problems of low Reynolds numbers and reduced air density, resulting in efficient airfoil design being critical. This study compared the NACA 63-618 and 64-618 airfoil at a Re = 2 x 10 6  through the use of XFOIL, while turbulence is modeled by adjusting the Ncrit values from 3-16. While both airfoils displayed similar lift results, the drag and efficiency were affected by the surface smoothness. The 63-618 had higher lift-to-drag ratios in smoother conditions, while the 64-618 was more stable in moderate turbulence. For both, maximum efficiency occurred at an angle of attack between 2 and 4 degrees. The results also suggested that an Ncrit of 7-8 is best representative for high-altitude performance for glider applications. 

References

Ashill, T. W., J. L. Fulker, and D. J. Weeks. Aeroelastic Flight Experiment (APEX): Description and Status. NASA, 1999. NASA Technical Memorandum 1999-209715. NASA Technical Reports Server, https://ntrs.nasa.gov/api/citations/19990049398/downloads/19990049398.pdf.

“The Sailplane That Will Fly to the Edge of Space.” Smithsonian Air & Space Magazine, National Air and Space Museum, 9 Sept. 2016, https://www.smithsonianmag.com/air-space-magazine/sailplane-stratosphere-180959154.

NACA 63(3)-618 (Naca633618-Il). http://airfoiltools.com/airfoil/details?airfoil=naca633618-il. Accessed 18 Sep. 2025.

NACA 64(3)-618 (Naca643618-Il). http://airfoiltools.com/airfoil/details?airfoil=naca643618-il. Accessed 18 Sep. 2025.

“AirfoilTools.” AirfoilTools, www.airfoiltools.com/

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Posted

2025-10-22

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Copyright (c) 2025 Shaswat Srivastava

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