journal article·2022-04-22Open access

Technological Aspects of a Reparation of the Leading Edge of Helicopter Main Rotor Blades in Field Conditions

Michał Sałaciński, Krzysztof Puchała, Andrzej Leski, Elżbieta Szymczyk, Volodymyr Hutsaylyuk, Arkadiusz Bednarz, Piotr Synaszko, Rafał Kozera, Klaudia Olkowicz, Dominik Głowacki

Applied Sciences· Volume 12· Issue 9

Abstract

The Polish Air Force operates more than one hundred helicopters of the Mi family (manufactured by Mil Helicopters), equipped with metal main rotor blades. The main rotor blades are among the most stressed components of these structures. For this reason, they are subject to more frequent inspections during operation than other components. One type of damage detected during inspections is the local disbonding of fragments of the anti-erosion layer from the leading edge. This harmless-looking damage is very dangerous, since it quickly leads to the complete detachment of the layer. The leading edge, unprotected by the metal cover, erodes rapidly. The detached layer, when thrown away at high speed, endangers other parts of the helicopter, such as the tail rotor, and may cause damage to other helicopters if flying in formation. The technology supplied by the manufacturer to date has not encompassed the field repair of this type of damage. Therefore, efforts were made to develop repair technology for rapid repairs of blades in field conditions during missions of the Task Force White Eagle in Afghanistan. This article presents the concept of repair technology feasible in field conditions and presents the results of post-repair edge tests. Test results to identify the materials used in the construction of the trailing edge are also presented. The results of materials testing facilitated the development of technological processes, and, in the future, will aid the selection of a substitute bonding paste system with similar parameters that are essential for repairs.
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Research context

OpenAlex topics: High-Velocity Impact and Material Behavior · Energetic Materials and Combustion · Rocket and propulsion systems research

SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.

Affiliations

Air Force Institute of Technology, Airworthiness Division, 01-494 Warsaw, Poland

Faculty of Mechanical Engineering, Military University of Technology, 00-908 Warsaw, Poland

Łukasiewicz—Institute of Aviation, 02-256 Warsaw, Poland

Faculty of Mechanical Engineering and Aeronautics, Rzeszów University of Technology, 35-959 Rzeszow, Poland

Faculty of Materials Science and Engineering, Warsaw University of Technology, 02-507 Warsaw, Poland

Faculty of Power and Aeronautical Engineering, Warsaw University of Technology, 00-665 Warsaw, Poland

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