  The structure of accretion curtain flows arising from magnetically disrupted
discs is considered. It is shown that a sub-Alfvenic, magnetically channelled
flow is consistent with matching the magnetic field across the curtain base. It
is shown that some angular momentum is necessarily fed back into the disc, and
this reduces the accretion torque acting on the star.
  The sonic point coordinates are found and a critical rotation rate results
below which the sonic point merges with the curtain flow base so, for such
stellar rotation rates, little or no thermal assistance is required for
material to make the transition to a supersonic flow.
