Newslink: NASA's Mars Helicopter Whirls Through Tests on Way to 2020 Launch
NASA's first Mars helicopter is getting close to final approval for launch after passing several key tests.
https://www.space.com/nasa-mars-helicopter-final-testing.html
NASA's first Mars helicopter is getting close to final approval for launch after passing several key tests.
https://www.space.com/nasa-mars-helicopter-final-testing.html