A little while ago, the SpaceX Crew Dragon spacecraft blated off atop a Falcon 9 rocket from the Cape Canaveral base in its SpX-DM1 (SpaceX Demonstration Mission 1) or SpaceX Demo-1 mission. After about eleven minutes it successfully separated from the rocket’s last stage and went on its way to carry out its mission. This is the first test of the Crew Dragon spacecraft with a journey to the International Space Station and back. In this case there’s no one on board but if all goes well in the next launch there will be the first transport of astronauts.
In September 2014 NASA announced that it had selected Boeing’s and SpaceX’s projects for the new phase of manned spacecraft development. The contract called Commercial Crew Transportation Capability (CCtCap) included the completion of the spacecraft with the initial idea of starting crew transport in 2017. Due to a series of delays only now they’re beginning the tests and if all goes well during 2019 they can start the first launches of astronauts on the new private spacecraft.
The Crew Dragon spacecraft is a version of what was called the Dragon 2 or V2 equipped with the systems needed to transport human beings. The Dragon 2 in its cargo version, called Cargo Dragon 2, will replace the space cargo ship currently used by SpaceX probably with the start of the new contract for the transport of cargoes to the International Space Station and back.
The Crew Dragon spacecraft was designed to carry up to seven people but it was decided to use it for no more than four people. That allows NASA to send limited cargoes with astronauts. In the SpX-DM1 mission there will be some cargoes for a total of just under 200 kg (about 400 lbs) but instead of humans there will be an Anthropomorphic Test Device (ATD), a version of the crash test dummies used to test cars fitted with sensors that will record the forces it will experience during the journey. This ATD, which is wearing the space suit developed by SpaceX, was nicknamed Ripley, like the protagonist of the Alien saga.
Cargo spacecraft’s missions take 2-3 days to reach the International Space Station because the maneuvers they need have greater margins to correct them in case of problems. In the transport of astronauts they try to make the journey as short as possible and the SpX-DM1 mission, even if unmanned, will take just over a day to arrive. Tomorrow, at about 11 UTC, the Crew Dragon will reach the Station and another difference compared to the space cargo ship is that it will not be captured by the Canadarm2 robotic arm but will dock directly to the International Docking Adapter (IDA) installed in August 2016. When the moment to start real missions comes, the Crew Dragon will remain docked up to 210 days, for this test the return is scheduled for March 8th.