SpaceX Crew Dragon Splashes Down after Historic Test Flight - Glad to hear that the mission was accomplished successfully, I'm struck by the accuracy that is required for these missions, for example once demo1 completes it's missions, they have validated the design and 1 instance of building the spaceship, but don't they then have to run the same tests on demo2 the astronaut carrying vehicle? How can they be sure that the build is an exact replica? There are so many moving partswww.scientificamerican.com #