Two barium plasma injection experiments were carried out during magnetically active periods in conjuction with the Skylan 3 mission. The high-explosive shaped charges were launched from Piker Flat near dawn on November 27 and December 4, 1973, UT. In both cases the AE index was near 400 &ggr;, and extensive pulsating auroras covered the sky. The first experiment, Skylab Alpha, occurred in the waning phase of a 1000-&ggr; substorm, and the second, Skylab Beta, occurred in the expansive phase of an 800-&ggr; substorm. In both, the convective was generally magnetically eastward, with 100-km-level electric fields near 40 mV/m. However, in the Alpha experiment the observed orientation of the barium flux tube fitted with theoretical field lines having no parallel current, but the Beta flux tube orientation indicated a substantial upward parallel sheet current. The Skylab Alpha experiment was observed and photographed by the crew of Skylab 3 for 4 1/2 min.