Zenit-C was a sounding rocket developed in Switzerland. The Zenit was a single-step rocket with a length of 5.6 meters, a diameter of 0.42 meter and a takeoff weight of 610 kilograms. Propelled by a solid-propellant engine which supplied a thrust between 45 kN at launch and 22 kN in flight, the Zenit could carry a payload of 25 kilograms to a height of 210 km or a payload of 130 kilograms to a height of 115 km. At its maiden flight on October 27, 1967 at Salto di Quirra the Zenit topped 145 km. The Zenit was later launched only twice — once on July 30, 1971 at Salto di Quirra with a British Cuckoo rocket as a starting stage and once on December 13, 1973 at Andøya likewise with a "Cuckoo" starting stage.