SOYUZ-TMA 21, also known as Soyuz TMA-21, is a crewed spacecraft launched on April 4, 2011, from the Tyuratam (Baikonur) Cosmodrome, LC1 launch pad using a Soyuz-FG launch vehicle. The satellite has dimensions of 7.9 meters in length and a diameter of 2.7 meters with a span of 10.6 meters. It was manufactured by RKKE and had a dry mass of 2902 kg at launch. SOYUZ-TMA 21 is equipped with two deployable fixed solar arrays and batteries for power supply. The spacecraft's shape consists of a cylinder, cone, sphere, and two panels (Pan). Its configuration is identified as 7K-STMA, and its mission was to serve as a crewed spacecraft.