Development of the Main Wing Structure of a High Altitude Long Endurance UAV

  • Sang Wook Park
  • Jeong Woo Shin
  • Tae-Uk Kim
Original Paper


To enhance the flight endurance of a HALE UAV, the main wing of the UAV should have a high aspect ratio and low structural weight. Since a main wing constructed with the thin walled and slender components needed for low structural weight can suffer catastrophic failure during flight, it is important to develop a light-weight airframe without sacrificing structural integrity. In this paper, the design of the main wing of the HALE UAV was conducted using spars which were composed of a carbon–epoxy cylindrical tube and bulkheads to achieve both the weight reduction and structural integrity. The spars were sized using numerical analysis considering non-linear deformation under bending moment. Static strength testing of the wing was conducted under the most critical load condition. Then, the experimental results obtained for the wing were compared to the analytical result from the non-linear finite-element analysis. It was found that the developed main wing reduced its structural weight without any failure under the ultimate load condition of the static strength testing.


Carbon-composite spar HALE UAV Non-linear structural analysis Structural testing 



This study was supported by ‘Study on the light structure and structural integrity improvement technology’ program funded by the National Research Council of Fundamental Science & Technology, Republic of Korea. Their support is gratefully acknowledged.


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Copyright information

© The Korean Society for Aeronautical & Space Sciences and Springer Nature Singapore Pte Ltd. 2018

Authors and Affiliations

  1. 1.Aircraft Structures Research Team, Fixed Wing Aircraft Research Office, Aeronautics Research and Development Head OfficeKorea Aerospace Research InstituteDaejeonRepublic of Korea

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