  Observations and modelling suggest that the fluctuations in magnetised
plasmas exhibit scale-dependent anisotropy, with more energy in the
fluctuations perpendicular to the mean magnetic field than in the parallel
fluctuations and the anisotropy increasing at smaller scales. The
scale-dependence of the anisotropy has not been studied in full-orbit
simulations of particle transport in turbulent plasmas so far. In this paper,
we construct a model of critically balanced turbulence, as suggested by
\cite{GoSr1995}, and calculate energetic particle spatial diffusion
coefficients using full-orbit simulations. The model uses an enveloped
turbulence approach, where each 2-dimensional wave mode with wavenumber
$k_\perp$ is packed into envelopes of length $L$ following the critical balance
condition, $L\propto k_\perp^{-2/3}$, with the wave mode parameters changing
between envelopes. Using full-orbit particle simulations, we find that both the
parallel and perpendicular diffusion coefficients increase by a factor 2,
compared to previous models with scale-independent anisotropy.
