  We investigate the disorder-driven phase transition from a fractional quantum
Hall state to an Anderson insulator using quantum entanglement methods. We find
that the transition is signaled by a sharp increase in the sensitivity of a
suitably averaged entanglement entropy with respect to disorder -- the
magnitude of its disorder derivative appears to diverge in the thermodynamic
limit. We also study the level statistics of the entanglement spectrum as a
function of disorder. However, unlike the dramatic phase-transition signal in
the entanglement entropy derivative, we find a gradual reduction of level
repulsion only deep in the Anderson insulating phase.
