NASA and SpaceX have agreed to launch Demo-2 to the International Space Station on May 27. Demo-2 is the crewed flight test of SpaceX’s Crew Dragon carrying NASA astronauts Bob Behnken and Doug Hurley, the first launch of astronauts to the ISS from American soil since the space shuttle program was terminated in 2011. If successful, Demo-2 will open the door for operational flights of Crew Dragon.

SpaceX and Boeing are developing crew space transportation systems through public-private partnerships with NASA. They own the spacecraft. NASA just buys services, but the companies must meet contractual requirements to demonstrate the systems are safe to transport NASA astronauts.

For SpaceX, that includes conducting an uncrewed flight test, Demo-1, completed in March 2019; a Pad Abort Test and an In-Flight Abort Test of a system to separate the spacecraft from the Falcon 9 rocket and return the crew safely to Earth in case of an emergency during launch, completed in May 2015 and January 2020 respectively; and now the crewed flight test, Demo-2.

NASA and SpaceX announced on March 18 that they planned to launch in mid-to-late May, but the question has been whether the COVID-19 pandemic would force a delay.

Apparently not. NASA announced today that the launch is scheduled for May 27 at 4:32 pm ET. It will take off from Launch Complex 39A at Kennedy Space Center (KSC), Florida, which SpaceX leases from NASA.

KSC is at Stage 3 of NASA’s Response Framework, with mandatory telework except for mission essential personnel.

The exact duration of the mission is to be determined. Originally it was going to be a short test flight of perhaps a week, but delays in the availability of the U.S. systems have led to a reduced crew complement on ISS that NASA is eager to resolve. Hence Demo-2 was extended to 2-3 months. This test version of the spacecraft can remain in space for up to 110 days. The operational version can stay for at least 210 days.

Only one NASA astronaut, Chris Cassidy, and two Russian cosmonauts, Anatoly Ivanishin and Ivan Vagner, are aboard ISS right now. They arrived last week and will remain until October.

Usually the crew complement is six — three each in two Soyuzes, rotating on roughly 6 month schedules — but Russia has reduced the number of annual Soyuz flights to ISS from four to two because the U.S. systems were supposed to be ready by now. Soyuz has been the only way to get to and from ISS since the end of the shuttle program. The three crew members who had been staffing the ISS returned to Earth hours ago after their own long duration missions.