Valery Kubasov, who has died aged 79, was a pioneer of spaceflight and one of the USSR's leading cosmonauts. His most striking achievement was The Apollo-Soyuz Test Project mission which led to the famous handshake in space.
It was the first joint space flight between the United States and Russia and was the first step towards the co-operation that led to the International Space Station.
In all, Kubasov flew three missions as a cosmonaut for the Soviet Union and spent more than 18 days in space. He was much decorated by the State, receiving the Order of Lenin, the Soviet Union's highest honor, but it was the Apollo-Soyuz Test Project that attracted the most fame and publicity - not only was it a triumph for both nations, it also raised hopes of more co-operation between the old enemies on earth as well as in space.
Kubasov was born in Vyazniki, northeast of Moscow, where his father was a mechanic, and trained as an aerospace engineer at the Moscow Aviation Institute in the 1950s. After graduating in 1958, he went to work for Sergei Korolev, one of the country's leading rocket engineers, before being selected to train as a cosmonaut in the mid-1960s.
His first mission was the Soyuz 6 flight in 1969, during which Kubasov used welding equipment in space, the first man to do so. It was an achievement that received much publicity in the Soviet Union, which was feeling the pressure of American success in space and needed to trumpet its achievements.
Kubasov was also due to be on board the Soyuz 11 mission in 1971 but had to pull out because of a lung infection. It was just as well for him - Soyuz 11 ended disastrously when the entire crew died on re-entry after their cabin de-pressurised.
The Apollo-Soyuz Test Project was launched in 1975 and was Kubasov's highest-profile mission. The idea of a joint American-Russian space mission had been raised by President Nixon three years before as part of détente and, after 18 months of joint training, the two crews blasted off on July 15 within a few hours of each other. They met in orbit two days later.
The two spacecrafts were locked for two days in all and the crews performed a number of scientific experiments. The famous handshake was performed through the open hatch of Soyuz by the two mission commanders Alexey Leonov and Tom Stafford.
Kubasov commanded his third and final flight into space, Soyuz 36, in 1980, and retired from the cosmonaut corps in 1993. He then served as deputy director for the aerospace corporation RSC Energia.
He is survived by his wife and their two children.