The Soviet Vostok and American Gemini spacecraft both made use of ejection seats. The European Space Agency's Hermes and the Soviet "Buran"-class spaceplanes would also have made use of them if they had ever flown with crews. As shown by Soyuz T-10a, an LES must be able to carry a crew compartment from the launch pad to a height sufficient for its parachutes to open. Consequently, they must make use of large, powerful (and heavy) solid rockets. The Soyuz launch escape system is called "CAC" or "SAS", from the Russian/transliterated Russian "Система Аварийного Спасения" or "Sistema Avariynogo Spaseniya", meaning emergency rescue system.