  We present a numerical study in resistive magnetohydrodynamics where the
initial equilibrium configuration contains adjacent, oppositely directed,
parallel current channels. Since oppositely directed current channels repel,
the equilibrium is liable to an ideal magnetohydrodynamic tilt instability.
This tilt evolution, previously studied in planar settings, involves two
magnetic islands or fluxropes, which on Alfvenic timescales undergo a combined
rotation and separation. This in turn leads to the creation of (near) singular
current layers, posing severe challenges to numerical approaches. Using our
open-source grid-adaptive MPI-AMRVAC software, we revisit the planar evolution
case in compressible MHD, as well as its extension to 2.5D and full 3D
scenarios. As long as the third dimension remains ignorable, pure tilt
evolutions result which are hardly affected by out of plane magnetic field
components. In all 2.5D runs, our simulations do show secondary tearing type
disruptions throughout the near singular current sheets in the far nonlinear
saturation regime. In full 3D, both current channels can be liable to
additional ideal kink deformations. We discuss the effects of having both tilt
and kink instabilities acting simultaneously in the violent, reconnection
dominated evolution. In 3D, both the tilt and the kink instabilities can be
stabilized by tension forces. As a concrete space plasma application, we argue
that interacting tilt-kink instabilities in repelling current channels provide
a novel route to initiate solar coronal mass ejections, distinctly different
from currently favored pure kink or torus instability routes.
