In order to establish a set of basic criterias for the evaluation of landing gear drop test by theoretical analysis, an approach using the requirements of the landing gear design or its equivalent forms is proposed to evaluate landing gear drop tests, and a set of all design requirements that fit the landing gear drop test of land-based aircrafts is given based on energy analysis. For the energy-dissipated design that cannot be verified directly, equivalent forms of energy dissipation requirements under different drop test conditions are developed by energy equivalent method. For the simulated air-borne impacts, the anti-stroke damping coefficient is defined to evaluate the capability of dissipating energy, and an equation for the relationship between the coefficient and the dissipated energy is established. Considering the limited time in the process of compression and rebound, the maximum value of the dissipated energy can be obtained with this equation. For the reduced-mass method, the relationship between energy dissipation and wheel motion is established, and the feasibility to avoid the jumpoff of the wheels is studied. The capabilities of the two methods for the drop test are compared, and the equivalent conditions of the two methods are given.
DU Jinzhu
,
MENG Fanxing
,
LU Xuefeng
. Criteria for evaluation of landing gear drop test based on energy method[J]. ACTA AERONAUTICAET ASTRONAUTICA SINICA, 2018
, 39(4)
: 221375
-221375
.
DOI: 10.7527/S1000-6893.2018.21375
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