Jack Fischer undergoes a leak check of his Russian Sokol launch prior to climbing aboard the spacecraft as part of pre-launch preparations.

In the Integration Building at the Baikonur Cosmodrome in Kazakhstan, Expedition 51 crewmember Jack Fischer of NASA undergoes a leak check of his Russian Sokol launch and entry suit April 6 prior to climbing aboard the Soyuz MS-04 spacecraft as part of pre-launch preparations. Fischer and Fyodor Yurchikhin of the Russian Federal Space Agency (Roscosmos) will launch April 20 on the Soyuz MS-04 spacecraft for a four and a half month mission on the International Space Station. NASA/Gagarin Cosmonaut Training Center/Andrey Shelepin