Trans Motauto World
Vol. 10 (2025), Issue 2, pg(s) 47-50

TRANSPORT TECHNICS. INVESTIGATION OF ELEMENTS. RELIABILITY

Study on the Additional Ballistic Protection for Military Transport Helicopters

  • 1 University of Defence, Brno, Czech Republic
  • 2 Namest nad Oslavou Air Base, Namest nad Oslavou, Czech Republic

Abstract

The article presents a comprehensive study on the enhancement of ballistic protection for the consumption fuel tank of the Mi-171 transport helicopter, which is deployed in conflict zones across various countries. The study examines the helicopter’s critical areas, evaluates the levels of ballistic protection, and proposes solutions for augmenting the consumption fuel tank’s protection against firing. Three variants of potential ballistic protection are suggested, utilizing commercially available armours: steel Hardox 450, aluminium alloy Al 7039, and titanium alloy Ti-6AL-4V. The analysis is conducted using the Ansys Workbench software, aiming to determine the required thickness of homogeneous armour to achieve ballistic level 2 according STANAG 4569, capable of withstanding penetration by 7.62 39 API BZ ammunition. The study estimates the ballistic limit thickness necessary to prevent perforation of the ballistic protection panel. The simulation procedure and the material models of the armours employed are thoroughly described. Additionally, the study evaluates the weight of the protection system to identify the material with the minimum weight, thereby preserving aircraft performance. Notably, the use of titanium alloy and steel results in the greatest reduction in the weight of the protective system, with their masses being nearly identical. In contrast, the aluminum alloy exhibits a mass that is approximately 11% higher. A method for installing the armours on the helicopter is also proposed. The findings of this study are valuable for analysing airframe structures that face ballistic threats during military operations or terrorist attacks. Proposals for further refinement and a shooting experiment are discussed to enhance the accuracy and effectiveness of the protection solutions.

Keywords

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