Research Article

Global Sensitivity of Constraint Analysis method: Drag coefficient and Stall Speed selection for Small UAVs

Volume: 6 Number: 4 September 12, 2026

Global Sensitivity of Constraint Analysis method: Drag coefficient and Stall Speed selection for Small UAVs

Abstract

The Constraint analysis method is applied in the early stages of aircraft conceptual design for determining preliminary sizing parameters such as wing loading and power loading. However, its application to small UAVs is challenged by uncertainties in several key input parameters, particularly those that require detailed geometric or aerodynamic information that is typically unavailable during the early design stages. To help designers to identify which parameters demand precise specification and which have negligible impact, a global sensitivity analysis was conducted. This allowed us to quantify the influence of each design parameter on constraint analysis outputs and classify them based on their influence. The results identify several dominant parameters. While some are predefined, the zero-lift drag coefficient requires detailed aerodynamic data that is unavailable early in design. To address this, we propose using parasite drag estimation method, adapted for small UAVs through the use of UAV-specific wetted-area ratios. A parametric study of stall speed shows that both power loading and wing loading exhibit a local maximum, suggesting that stall speed can be treated as a trade off parameter rather than a fixed requirement. For UAV designers, this work provides: (1) a sensitivity framework for constraint analysis, and (2) practical methods for selecting appropriate values for drag coefficient and stall speed during the early design stages.

Keywords

References

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  8. Tyan, M., Nguyen, N. V., Kim, S., & Lee, J.-W. (2017). Comprehensive preliminary sizing/resizing method for a fixed-wing–VTOL electric UAV. Aerospace Science and Technology, 71, 30–41. https://doi.org/10.1016/j.ast.2017.09.008

Details

Primary Language

English

Subjects

Mechanical Engineering (Other)

Journal Section

Research Article

Publication Date

September 12, 2026

Submission Date

May 13, 2026

Acceptance Date

August 18, 2026

Published in Issue

Year 2026 Volume: 6 Number: 4

APA
Sidi Moulay, S. M., & Mohamed Elamine, A. A. (2026). Global Sensitivity of Constraint Analysis method: Drag coefficient and Stall Speed selection for Small UAVs. Engineering Perspective, 6(4), 576-583. https://doi.org/10.64808/engineeringperspective.1950246
AMA
1.Sidi Moulay SM, Mohamed Elamine AA. Global Sensitivity of Constraint Analysis method: Drag coefficient and Stall Speed selection for Small UAVs. engineeringperspective. 2026;6(4):576-583. doi:10.64808/engineeringperspective.1950246
Chicago
Sidi Moulay, Sidi Moulaye, and Ait Ali Mohamed Elamine. 2026. “Global Sensitivity of Constraint Analysis Method: Drag Coefficient and Stall Speed Selection for Small UAVs”. Engineering Perspective 6 (4): 576-83. https://doi.org/10.64808/engineeringperspective.1950246.
EndNote
Sidi Moulay SM, Mohamed Elamine AA (September 1, 2026) Global Sensitivity of Constraint Analysis method: Drag coefficient and Stall Speed selection for Small UAVs. Engineering Perspective 6 4 576–583.
IEEE
[1]S. M. Sidi Moulay and A. A. Mohamed Elamine, “Global Sensitivity of Constraint Analysis method: Drag coefficient and Stall Speed selection for Small UAVs”, engineeringperspective, vol. 6, no. 4, pp. 576–583, Sept. 2026, doi: 10.64808/engineeringperspective.1950246.
ISNAD
Sidi Moulay, Sidi Moulaye - Mohamed Elamine, Ait Ali. “Global Sensitivity of Constraint Analysis Method: Drag Coefficient and Stall Speed Selection for Small UAVs”. Engineering Perspective 6/4 (September 1, 2026): 576-583. https://doi.org/10.64808/engineeringperspective.1950246.
JAMA
1.Sidi Moulay SM, Mohamed Elamine AA. Global Sensitivity of Constraint Analysis method: Drag coefficient and Stall Speed selection for Small UAVs. engineeringperspective. 2026;6:576–583.
MLA
Sidi Moulay, Sidi Moulaye, and Ait Ali Mohamed Elamine. “Global Sensitivity of Constraint Analysis Method: Drag Coefficient and Stall Speed Selection for Small UAVs”. Engineering Perspective, vol. 6, no. 4, Sept. 2026, pp. 576-83, doi:10.64808/engineeringperspective.1950246.
Vancouver
1.Sidi Moulaye Sidi Moulay, Ait Ali Mohamed Elamine. Global Sensitivity of Constraint Analysis method: Drag coefficient and Stall Speed selection for Small UAVs. engineeringperspective. 2026 Sep. 1;6(4):576-83. doi:10.64808/engineeringperspective.1950246

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