Vyacheslav Zudov, a Soviet-era cosmonaut who attempted to dock with a Russian space station but failed, resulting in the first and only emergency splashdown in a Soyuz spacecraft, has died at the age of 82.

His death was reported by Roscosmos, Russia’s federal space corporation, on Wednesday (June 12). The agency’s statement read, «His two-day spaceflight became, without exaggeration, dramatic.» «The landing of ‘Radon’ (the call sign that the cosmonaut chose for himself) proved to be no less perilous.»

Selected for the cosmonaut corps with the third group of Soviet Air Force recruits in October 1965, Zudov was selected to command his inaugural and, as it would turn out, his sole spaceflight. On October 14, 1976, he and pilot Valery Rozhdestvensky launched on board Soyuz 23 with the intention of spending at least two weeks, if not two to three months, on the Salyut 5 space station. The Soyuz 23 flight was designed to resume operations at the orbiting outpost following the termination of a previous Soyuz crew’s mission earlier that year. Instead, Zudov and Rozhdestvensky encountered a comparable outcome. During their approach to Salyut 5, the autonomous docking system failed, leaving no alternative for Zudov and Rozhdestvensky to reach the space station. They had been trained on how to manually dock, but lacked the requisite skills to fly a rendezvous. Abandoning their mission and constrained by the Soyuz’s battery reserves, the two cosmonauts spent a day in orbit and then initiated their descent back to Earth. The Soviet Union developed the Soyuz to land on land, employing a main parachute and braking thrusters to facilitate a «soft» landing. Cosmonauts underwent training for contingency water landings, yet such a splashdown had yet to occur.

The Soyuz 23 spacecraft was designed to land near its launch site at the Baikonur Cosmodrome (present-day Kazakhstan). However, unfavorable weather conditions prevented the spacecraft from reaching its intended destination. Instead, it descended 1.2 miles (2 kilometers) off the shore of Lake Tengiz, which had partially frozen over by mid-October. The Soyuz’s main parachute did not separate as intended, and its reserve canopy was deployed inadvertently. Once saturated, both chutes acted as an anchor, pulling the capsule below the water. Despite the efforts of rescue teams, who were able to reach the site, the local conditions delayed their ability to access the capsule. Zudov and Rozhdestvensky were forced to power down and remain inside the spacecraft for several hours until their descent module could be hauled out of the water and onto solid land. Zudov and Rozhdestvensky were cold but healthy. The total time spent in space was 2 days and 6 minutes.

Vyacheslav Dmitriyevich Zudov was born on January 8, 1942, in Bor, a town on the left bank of the Volga River across from Nizhny Novgorod in Russia. He graduated from the Higher Military Pilot School in Balashov in 1963 and subsequently became a military transport pilot in the Soviet Air Force.

In addition to his own Soyuz 23 mission, Zudov served as backup commander for the Soyuz 15, Soyuz 21, Soyuz 35, and Soyuz T-4 missions before he retired from the cosmonaut corps on May 14, 1987. For his service to the space program, Zudov was named Hero of the Soviet Union and awarded the Order of Lenin, among other honors.

Zudov was married to Nina Nikitina and together they had two daughters, Natalya and Yelena. He was preceded in death by his Soyuz 23 crewmate, Rozhdestvensky, who died in 2011.

A memorial service for Zudov will be held on Friday, June 14, at the Federal Military Memorial Cemetery, a national cemetery of Russia, located on the northeastern outskirts of Moscow.