US space agency NASA said on Thursday its industry partners, Boeing and SpaceX, are targeting the return of human spaceflight from Florida's Space Coast in 2018."Both companies are scheduled to begin flight tests to prove the space systems meet NASA's requirements for certification in the coming year," Xinhua quoted NASA as saying."Boeing's Starliner will launch on a United Launch Alliance Atlas V rocket from Space Launch Complex 41 and SpaceX's Crew Dragon will launch on the company's Falcon 9 rocket from Launch Complex 39A."Boeing is expected to perform an uncrewed flight test in August, during which the unmanned Starliner will dock to the International Space Station for about two weeks.Then, the company will fly the Starliner spacecraft for its first commercial spaceflight to the International Space Station in November with two crew members on board.Meanwhile, SpaceX is targeting the second quarter of 2018 for its first uncrewed demonstration mission with Crew Dragon to and from the International Space Station.It will be followed by a crewed mission in the third quarter of 2018 that will see two NASA astronauts flying to and from the International Space Station in SpaceX' s Crew Dragon spacecraft.The two crewed missions by Boeing and SpaceX "represent a major milestone in the return of human spaceflight from the United States," NASA was quoted as saying.If everything goes well, the companies are each slated to fly six crew missions to the International Space Station beginning in 2019 and continuing through 2024, it added.