Per Spaceflight Now:

NASA is sure enough that Boeing and SpaceX can safely launch astronauts to the International Space Station by early 2019 to hold off paying Russia to keep flying U.S. crews to the research complex, and one official says a deadline to order parts for new Russian Soyuz crew capsules may have already passed.

Boeing and SpaceX are working on new commercial capsules designed to transport at least four astronauts to and from the orbiting outpost, but their schedules appear to be slipping, this time due to technical woes, not the lack of funding that caused previous delays in the program.

Until the U.S.-built spaceships are certified by NASA, all space station crews will launch and land aboard Russian Soyuz spacecraft.

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