BREVARD COUNTY, Fla. — On Thursday afternoon, the first astronaut crews of the CST-100 Starliner toured Boeing's Commercial Crew and Cargo Processing Facility at Kennedy Space Center.
For the first time, astronauts saw the vessel that will transport them to the International Space Station.
"It's almost like the icing on the cake," NASA Astronaut Suni Williams said.
[ Read: Astronauts selected to crew first flight tests bring 'new era in American spaceflight' ]
NASA Astronaut Nicole Mann said seeing the vessel for the first time is a great experience.
"I've never flown in space before, so to be around the hardware and all the people (who) are building everything is just incredible," she said.
[ Crews will be separated into two groups that will travel to the ISS in 2019. ]
Unmanned tests are scheduled to begin by the end of the year or early next year.
"We want to make sure it happens correctly so it comes back so we can fly it," Williams said.
Scientists and engineers on Thursday worked on three vessels designed to remain in orbit for up to seven months and to be used for as many as 10 missions.
[ Read: 'We're ready to do more,' new NASA administrator says after 1st KSC visit ]
The astronauts are expected to be in space between two weeks to a year.
"It's been seven years since we launched a shuttle, and I think it's going to be good not only for our commercial companies (and) for NASA, but really for all of America."
A manned test flight has been delayed several times for further testing.