STS 37, also known as Atlantis (STS-37), is a US crewed spacecraft operated by JSC and manufactured by RWI. Launched on April 5, 1991, from LC39B at AFETR using the Space Shuttle launch vehicle, it has a winged orbiter configuration with dimensions of 37.3 meters in length and span, and 23.8 meters in diameter. The spacecraft's dry mass is 84,467 kilograms while its launch mass was 91,847 kilograms. STS 37 features fuel cells and batteries for power supply and two OME (AJ10-190) motors. Its mission purpose was to serve as a crewed spacecraft with a shape described as Box + 2 Wing + Fin.