  The dynamics of fibres, modelled as a sequence of inertial beads linked via
elastic springs, in turbulent flows is dictated by a non-trivial interplay of
their inertia and elasticity. Such elastic, inertial fibres preferentially
sample a three-dimensional turbulent flow in a manner qualitatively similar to
that in two-dimensions [Singh et al., Phys. Rev. E 101, 053105 (2020)]. Inertia
and elasticity have competing effects on fibre dynamics: Inertia drives fibres
away from vortices while elasticity tends to trap them inside. However, both
these effects are reversed at large values. A large inertia makes the fibres
sample the flow more uniformly while a very large elasticity facilitates the
sampling of straining regions. This complex sampling behaviour is further
corroborated by quantifying the chaotic nature of sampled flow regions. This is
achieved by evaluating the maximal Lagrangian Lyapunov Exponents associated
with the flow along fibre trajectories.
