Service module for OA-4 Cygnus arrives at KSC in lead up to December launch

Photo Credit: NASA
Orbital ATK has shipped the Service Module of the next Cygnus spacecraft to Kennedy Space Center in Florida in preparation for its upcoming flight. The OA-4 Cygnus will be launched atop a United Launch Alliance (ULA) Atlas V rocket from Cape Canaveral Air Force Station’s Space Launch Complex 41. If things continue to move at their current pace, that flight should lift off on December 3.
With its arrival at Kennedy, the Service Module and Cygnus’ extended pressurized cargo module (PCM), which is already at Kennedy Space Center, will be integrated with on another. The spacecraft will then be loaded with supplies and fueled before the full “stack” is mated to the Atlas V booster.
Cygnus’ service module is the part of the spacecraft that contains the vehicle’s avionics, propulsion, electrical, and communications systems.
The flight will be the first of two that Cygnus will undertake on an Atlas V as well as the first time Orbital ATK will deploy the “enhanced” version of the spacecraft, which will allow the vehicle to deliver the amount of cargo it is designed to ferry – 7,700 lbs (3,493 kg) scheduled to be sent to orbit on this flight.

The OA-4 mission will mark the first time that the enhanced version of Cygnus is planned to take flight (archive photo). Photo Credit: Patrick Black / NASA
“These are exciting times for the Cygnus team at Orbital ATK,” said Frank Culbertson, a former astronaut and President of Orbital ATK’s Space Systems Group. “With OA-4 set to launch in December and at least three additional missions to the Space Station planned in 2016, we remain solidly on schedule to meet our CRS cargo requirements for NASA. Our team’s performance in meeting milestones on an accelerated timeline demonstrates the company’s flexibility and responsiveness to customer needs.”
Orbital ATK was selected by NASA to develop and employ systems to send cargo and supplies to the International Space Station under the $1.9 billion Commercial Resupply Services (CRS) contract that the company has with NASA.
As noted during an interview on SpaceFlight Insider in March of this year, the capacity provided by the 401 configuration of the Atlas V will allow for the increased amount of crew supplies, equipment, and scientific experiments to astronauts on board the ISS sent on the OA-4 mission (as well as the use of the enhanced version of Cygnus).
The enhanced version of Cygnus has also been fitted with a lightweight space-qualified power system as well as UltraFlex solar arrays. OA-4 will mark the first use of these arrays.
Orbital ATK noted that the firm works to have most of the vehicles it produces to be capable of being flown on an array of launchers. This decision paid off after the Oct. 28 mishap. Orbital ATK purchased an Atlas V (and then an additional one) so that Dulles, a Virginia-based firm, could honor its commitments under CRS.
The OA-4 flight will be the first mission for Cygnus since the Oct. 28, 2014, loss of an Orbital ATK booster and its Cygnus cargo freighter.
Even before the accident, the firm was moving away from the Aerojet Rocketdyne-produced AJ-26 rocket engines that appear to have been the root cause of the accident; this according to a report appearing on NASASpaceFlight.com. If everything goes as planned, this new version of Antares will use the RD-181 engine – and could fly as early as March of 2016.
Around this same time frame that the second flight of a Cygnus on an Atlas V is scheduled to occur (Spring of 2016), Orbital ATK will also work to field the new enhanced version of its Antares booster.
The aerospace firm issued a statement noting that the next three Cygnus PCMs as well as the Service Modules for the three CRS missions that are slated to be carried out in 2016 are essentially complete and will be sent to KSC approximately two months prior to their individual launch dates.

Orbital ATK is working to return the Antares booster to service in March of 2016. Photo Credit: Chris Perry / NASA
Jason Rhian
Jason Rhian spent several years honing his skills with internships at NASA, the National Space Society and other organizations. He has provided content for outlets such as: Aviation Week & Space Technology, Space.com, The Mars Society and Universe Today.