Mathematical modelling of helicopter twin sling underslung dynamics using Kane’s matrix formulation
Prashant G. IYER, Jinu KRISHNAN, K.S. MANSOOR, Sheethal ANTONY
Abstract. For a winged body underslung attached to a helicopter using a single sling, side force and yawing moment coefficients play a significant role in determining the stability of the system. Instability in yaw plane due to lower dynamic pressure during helicopter take-off and touchdown can result in excessive cable twisting which can be detrimental for the mission and these lateral plane instabilities restrict the airspeed and maneuverability of the helicopter. Twin sling underslung system solves the issues by offering the advantage of enhanced load stability along with improved stability and balance for the awkwardly shaped loads. This paper describes mathematical modelling of a helicopter slung body dynamics in twin sling configuration, wherein the system dynamics is captured using a three-body, four degrees of freedom mathematical model with the differential equations of motion derived using matrix form of Kane’s method. The model is validated by comparing the results against a commercially available software in presence of dissipative aerodynamic forces. Further considering a sample helicopter trajectory from helicopter takeoff to touchdown, the slung body dynamics due to configuration update from single sling to twin sling is compared, and the advantages of the modified configuration clearly brought out.
Keywords
Multi-Body Dynamics, Twin Sling Underslung, Kane’s Method, Equations of Motion
Published online 3/1/2025, 10 pages
Copyright © 2025 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA
Citation: Prashant G. IYER, Jinu KRISHNAN, K.S. MANSOOR, Sheethal ANTONY, Mathematical modelling of helicopter twin sling underslung dynamics using Kane’s matrix formulation, Materials Research Proceedings, Vol. 49, pp 253-262, 2025
DOI: https://doi.org/10.21741/9781644903438-25
The article was published as article 25 of the book Mechanical Engineering for Sustainable Development
Content from this work may be used under the terms of the Creative Commons Attribution 3.0 license. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
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