The launch of the Orbital Sciences/ATK Cygnus CRS-4 mission to the International Space Station (ISS) has been aborted for a second time due to high ground winds. According to NASA, the 5:55 pm EST launch of the unmanned commercial cargo ship atop an Atlas V rocket was going without a hitch until high winds rose in the last half hour. After several holds, Atlas launch control scrubbed the attempt at 5:59 pm.
Shortly after the order came to stand down, a launch control spokesman explained that high ground winds from the northeast could have caused the Atlas V rocket to drift into the gantry during liftoff. The launch has now been rescheduled to 5:10 pm EST Saturday.
Today's scrub marks the second delay for the CRS mission, which is slated to carry 7,745 lbs (3.513 kg) of supplies and experiments to the ISS by the enhanced Cygnus spacecraft. It has a greater payload capacity, new UltraFlex solar arrays, and new fuel tanks. In addition, due to Orbital Sciences' Antares rocket being out of commission after a launch pad explosion that destroyed the Orbital Sciences/ATK Cygnus CRS-3 mission, this is the first Cygnus launch using the ULA Atlas V launch system.
Source: NASA