Launch from Cape Canaveral (KSC); landing on Edwards AFB.

Main goal of this mission was to deploy the Gamma Ray Observatory (GRO) with a weight of 17,5 t, on flight day three. There was a need of an unscheduled EVA performed by Jerry Ross and Jerome Apt on April 07, 1991 (4h 24m) to free and deploy the failed GRO high-gain antenna. A second (scheduled) EVA by Jerry Ross and Jerome Apt occured on April 08, 1991 (6h 11m) to test moving themselves and equipment for the planned ISS. The spacewalk was to test methods of moving crew members and equipment around the future Space Station.

Several other experiments included the Space Station Heat Pipe Advanced Radiator Experiment (SHARE II) and the Bioserve Instrumentation Technology Associates Materials Dispersion Apparatus (BIMDA) to explore the commercial potential of experiments in the biomedical, manufacturing processes and fluid sciences fields, as the SAREX (Shuttle Amateur Radio Experiment) and the Protein Crystal Growth experiment.