Enlarge / The Crew Dragon spacecraft sits atop a Falcon 9 rocket, with the crew access arm extended. (credit: SpaceX) Officials from NASA and SpaceX said final preparations were underway for a critical flight test of Crew Dragon's launch escape system on Saturday morning from Kennedy Space Center in Florida. The four-hour launch window opens at 8am ET (13:00 UTC), and SpaceX indicated it may use much of that time to find an ideal slot due to weather conditions. At the beginning of the launch window, weather at the pad should be ideal, but forecasters have concerns about offshore winds and waves.