The argon release controlled studies (ARCS 1--3) rocket flights carried ion generators to altitudes of 400--500 km in the nighttime auroral ionosphere. Three distinct electrical charging and neutralization processes were seen on the payloads during gun operation: steady or dc vehicle charging, brief charging at gun turn-on, and extended oscillatory sequences. Many of the unexpected consequences of gun firings are attributed to these payload charging and neutralization processes. Electrical charging is regulated by the rate at which low-energy electrons escape from the generator, which in turn is dependent on magnetic field geometry. Each ion generator produced a dipolar magnetic field which merged with the Earth's field near the rocket. The resulting local magnetic field guided electrons back to the rocket for certain gun orientations, thereby inhibiting neutralization. Transient charging was attributed to the formation of an electron cloud around at least some vehicles, while dc charging altered the rocket's surroundings until the electron escape rate balanced the ion beam flux. We concluded that during oscillatory events the entire environment of a payload could alternate between hot electron and cold electron configurations at very high rates, possibly exceeding 10 kHz. There changes in the plasma environment did not produce substantial electric field perturbations at the dc or ac high impedance electric field sensors, so were not seen in data from typical wave detectors. However, changes in plasma density and temperature produced dramatic effects on low impedance electric current sensors such as Langmuir probes. These observations illustrate the importance of carrying both low and high impedance detectors on vehicles involved in active experiments. A number of possible future experiments are suggested to test and extend our understanding of the proposed charging and neutralization mechanisms. ¿ American Geophysical Union 1989