[en] The longitudinal electric field associated with the observed electrostatic turbulence in the solar wind is shown to modify the dispersive characteristics of the hydromagnetic waves propagating along the interface between the solar wind and the cometary plasma. Extremely weak turbulence has a tendency to stabilize these surface waves, whereas turbulence of moderate level can be stabilizing or destabilizing depending on the strength of the cometary magnetic field Bsub(oc) relative to the interplanetary magnetic field Bsub(os). For Bsub(oc) >or approx. Bsub(os), destabilization is not possible. (author)