Direct measurements of the thermal ionospheric ion distribution function made from two sounding rockets launched into the expansive phase of an auroral substorm are discussed. Ion flows perpendicular (convective) and parallel to the geomagnetic field lines are derived from these observations at altitudes from 200 to 840 km. Equivalent convective electric fields were observed to vary between a few tens of millivolts per meter to over 150 mV/m and are shown to be highly correlated with energetic electron precipitation. High-velocity (up to 2 km/s) parallel ion flows were observed at various times and also found to be correlated with auroral electron precipitation. A correlation analysis of perpendicular (or equivalent electric fields E⊥) and parallel ion flow velocities with energetic electron intensities I at various energies is presented. The form of the E⊥ versus the logarithm of I relationship is shown to be approximately linear over most of the observed E⊥ range. Ionospheric 'line-tying' models are presented and compared with the measured E⊥ versus I relationship. The model is found to be most consistent with observations when magnetospheric forces are assumed to be independent of the instantaneous values of E⊥ and I rather than viscouslike. No evidence was found to suggest that decoupling of magnetospheric and ionospheric convection through parallel electric fields produced the observed anticorrelation of E⊥ and I.