Cygnus cargo flight set for launch to space station

This caused the flight of a United Launch Alliance Atlas V 401 rocket with Orbital ATK’s Cygnus spacecraft to be scrubbed.

Forecasters put the odds of good weather at 60 percent for Thursday’s 5:55 p.m. EST launch attempt. Early Friday afternoon, the forecast improved slightly, with thick clouds still the main concern for the planned 5:33 p.m. liftoff. Launch of the Atlas V is scheduled for Thursday evening. The redesigned Cygnus – along with the additional power supplied by the Atlas V rocket – is capable of carrying 7,700 pounds (3,500 kilograms) of cargo and scientific experiments to the space station.

Orbital arranged to use United Launch Alliance’s Atlas V rocket while it upgrades its Antares rocket, which failed due to a problem with its reconditioned Ukrainian engine. That work has required only minor modifications to the stage itself, said Mike Pinkston, vice president and general manager of the Antares program at Orbital ATK, in a December 3 interview.

Nasa hopes to resume commercial shipments this week to the International Space Station, following months of frustrating delay.

The Orbital Sciences/ATK Cygnus CRS-3 mission was lost when its Antares launcher exploded on the pad on October 28, 2014 at NASA’s Wallops Flight Facility.

The Orbital launch failure was the first of three station resupply mishaps that included the loss of a Russian Progress supply ship in April and a SpaceX Dragon cargo ship in June.

Virginia-based Orbital is modifying the Antares, replacing its AJ-26 first-stage engines with RD-181 engines, and the revamped version of the booster should be ready to fly sometime next year, company representatives have said. Elon Musk’s aerospace company will launch about one dozen uncrewed missions to the ISS under a deal with the USA space agency.

If no other supplies reach the station, the crew will hit reserve supplies of food in April 2016, NASA said.

The Deke Slayton II is the first ISS-bound spacecraft that had been previously worked on inside the space station.