The Support of an Aircraft for Ground Resonance Tests: A Survey of Available Methods

Abstract

The current trend in ground resonance testing is aimed at providing aircraft modes of vibration appropriate to the free‐free condition. To achieve this objective the rigid body frequencies of the aircraft on its supports must be low by comparison with the frequency of any mode of distortion. A minimum frequency ratio of 1:3 is specified. The various types of support in current use are considered in relation to the minimum frequency they are likely to provide. It appears that none are capable of frequencies lower than about 0·5 cycles/sec. For the forthcoming generation of large thin‐wing aircraft with fundamental frequencies below 1 cycle/sec. some further development in methods of support seems necessary. A non‐linear spring system appears to hold great promise in this respect, and one such system is described capable of frequencies less than 0·25 cycles/sec. for a limited range of movement.

Citation

Molyneux, W.G. (1958), "The Support of an Aircraft for Ground Resonance Tests: A Survey of Available Methods", Aircraft Engineering and Aerospace Technology, Vol. 30 No. 6, pp. 160-166. https://doi.org/10.1108/eb032976