The agency on Wednesday selected March 2 as the date for the first unmanned test flight, and an undisclosed date in July for when U.S. spacemen finally get shot back into orbit from American soil.
In order to meet NASA's requirements, both SpaceX and Boeing must demonstrate an ability to safely and efficiently transport crews into space. SpaceX and NASA didn't specifically disclose why they had to reschedule the Crew Dragon test flight date, but it's likely due to safety precautions.
NASA said the revised dates "allow for completion of necessary hardware testing, data verification, remaining NASA and provider reviews, as well as training of flight controllers and mission managers".
SpaceX will launch a Falcon 9 with the astronaut-ready space capsule from NASA's Kennedy Space Center Launchpad 39A.
If schedules hold, the crewed launches this summer will be the first to take off from USA soil carrying humans to low-Earth orbit since the end of the Space Shuttle program in 2011.
After the Crew Dragon completes its first test flight, SpaceX aims to have the capsule's first manned mission take place in July, which is a bit later than planned. The Dragon test was most recently delayed from January.
Commercial crew test flight schedule slips again
The capsule then will be readied for an in-flight abort test in June. SpaceX already has conducted a successful on-pad abort test.
The agency now is targeting March 2 for launch of SpaceX's Crew Dragon on its uncrewed Demo-1 test flight.
Whenever they take off, Behnken and Hurley plan to stay aboard the station for about a week before returning to Earth with another Atlantic Ocean splashdown.
According to NASA, United Launch Alliance is finalizing processing for the Atlas V rocket that will provide the thrust for the Starliner launch from Cape Canaveral Air Force Station's launch complex 41.
Boeing, meanwhile, is targeting no earlier than April for its first launch of a Starliner crew capsule from Cape Canaveral, also without a crew. Unlike the Crew Dragon, the Starliner is created to land in the western United States using parachutes and airbags. The rocket performed a static fire test on the pad January 24 that the company said was successful.
These changes push both companies' first launches with astronauts into the late summer. Operational flights will begin sometime thereafter, assuming everything goes well.