Orbital Sciences will not be launching a demonstration of its Antares launched Cygnus cargo ship to the International Space Station by the end of 2012 as originally planned. In an announcement made October 18, the company laid out a new schedule that puts the first test launch as late as the second quarter of 2013.
The announcement was made in a conference call with investors and did not indicate any particular cause for the delay. A propellant loading test for Antares is scheduled for October 21, with a 30 second test fire to follow in early November. Antares testing will take place at the Wallops Island spaceport in Virginia from which all Antares launches are also expected to take place. The first Antares test flight is planned for December.
Antares is a medium class expendable launch vehicle designed to launch payloads up to 5,000 kg into low Earth orbit. It uses kerosene/liquid oxygen propellant with an optional bipropellant third stage. The unmanned Cygnus capsule consists of two sections: the cargo module and the service module. The cargo module, which is pressurized and has an interior volume of 18m3 is manufactured by Thales Alenia Space. Orbital Sciences manufactures the service module itself. The solar powered vessel is expected to have a wet mass of 1800 kg. A second generation Cygnus is planned that will increase interior volume to 27 m3. Cygnus will berth to ISS with the help of the station’s robotic arm, much like Dragon.
Orbital Sciences is under contract to provide eight supply runs for NASA. Unlike Dragon, Cygnus is not able to return supplies since it reenters Earth’s atmosphere destructively as do the Progress, HTV, and ATV supply vessels.
Below, representation of a typical Cygnus mission: