Cygnus cargo vehicle gearing up for debut flight
BY STEPHEN CLARK
Posted: September 4, 2013
Orbital Sciences Corp. is almost ready to send the first commercial Cygnus cargo freighter on a demonstration mission to the International Space Station, and NASA officials gave the green light Wednesday for engineers to begin final preparations for the test flight's Sept. 17 launch on an Antares rocket from the Virginia coastline.
SpaceX, the start-up space transportation firm founded by Elon Musk, is NASA's other commercial cargo contractor. SpaceX completed the first test flight of its Dragon spacecraft to the space station in May 2012, and the California-based company has made two operational resupply runs to the outpost since then.
The Cygnus spacecraft gives NASA redundancy in case one of the two cargo providers encounters problems.
"The workhorses of the fleet for the U.S. segment [of the space station] will be the SpaceX vehicle and the Orbital vehicle," said Mike Suffredini, NASA's space station program manager. "We have them lined up to use them fairly regularly."
NASA and Orbital Sciences officials met Wednesday at the Johnson Space Center in Houston to review the status of preparations for the flight and discuss any concerns leading up to the launch.
According to Suffredini, officials identified no issues threatening a successful on-time launch, other than the standard processing left to go on the Antares rocket and Cygnus spacecraft.
The departure of a Japanese H-2 Transfer Vehicle on Wednesday also cleared a hurdle before the Cygnus flight can proceed. The HTV occupied the same port on the space station needed for the Cygnus spacecraft.
Orbital's Cygnus spacecraft and SpaceX's Dragon capsule were developed in a public-private partnership with NASA. The private companies own and operate the vehicles, but NASA provided funds and expertise to guide Orbital and SpaceX engineers through development and testing.
NASA's financial agreement with Orbital Sciences is worth $288 million, part of the agency's Commercial Orbital Transportation Services, or COTS, program.
Alan Lindenmoyer, NASA's COTS program manager, said the commercial cargo initiative started seven years ago with the intention of reducing the cost and complexity of sending supplies to the space station. Another objective was to make the resupply fleet responsive and capable of launching when needed.
"Last year, we came very close to seeing that vision become a reality with our first COTS partner SpaceX completing a demo flight to the space station and following up with operational flights to the space station," Lindenmoyer said Wednesday. "It was an amazing success, and here we are today with the opportunity to reinforce that capability with our second commercial partner ready to provide those services to the space station."
The development of the Cygnus spacecraft cost about $300 million, and the Antares rocket cost a little more to design and test, according to Frank Culbertson, executive vice president and general manager of Orbital's advanced programs group.
In an interview earlier this year, Culbertson declined to provide a specific value for the development of the Antares launcher. The new Antares launch pad, built by the Virginia Commercial Space Flight Authority, cost about $140 million.
Including investments from NASA, Orbital and the Commonwealth of Virginia, the Antares rocket, Cygnus spacecraft and the new launch pad collectively cost nearly $1 billion.
Orbital officials said the Cygnus spacecraft was scheduled to be attached to the upper stage of the Antares launcher Wednesday. Final cargo loading into the Cygnus spacecraft's pressurized module is set for Saturday, followed by its enclosure inside the rocket's 12.8-foot-diameter payload fairing.
Rollout of the Antares rocket from its horizontal integration facility to the launch pad one mile away is expected Sept. 13.
Launch aboard an Antares rocket on Sept. 17 is scheduled for 11:16 a.m. EDT (1516 GMT) from launch pad 0A at the Mid-Atlantic Regional Spaceport at NASA's Wallops Flight Facility on Virginia's Eastern Shore.
The 133-foot-tall Antares rocket sailed through a test launch in April, deploying a mock-up Cygnus spacecraft in orbit after smooth burns of its twin-engine first stage and solid-fueled second stage motor.
If all goes according to plan, the Antares will release the Cygnus spacecraft in orbit about 10 minutes after liftoff.
Then the Cygnus spacecraft will begin its own mission, exercising its software, engines, and other systems to ensure the vehicle is in top condition before it is trusted to approach within the space station's safety corridor on autopilot.
Under the control of Orbital Sciences engineers based in the company's Dulles, Va., headquarters, the Cygnus will extend its solar arrays, activate its propulsion system and start firing its thrusters to pace its approach to the International Space Station, where it is due to arrive Sept. 22.
Astronaut Luca Parmitano will guide the space station's robot arm to reach out and grapple the Cygnus spacecraft as it floats just below the outpost. The robot arm will move the Cygnus to a berthing port on the space station's Harmony module, where it will stay for about 30 days as the crew opens hatches and starts to unpack 1,500 pounds of food and other gear carried inside the vehicle's pressurized module, which is built by Thales Alenia Space of Italy.
Future Cygnus flights will haul more cargo, but Suffredini said NASA requested a light load on the demonstration mission - mostly low-priority supplies that officials would not miss if lost.
The astronauts will place trash and other equipment for disposal into the Cygnus compartment before the automated spacecraft's departure in October. Like the space station's Japanese, European and Russian supply vehicles, the Cygnus will burn up in the atmosphere during re-entry.
SpaceX's Dragon capsule is the only operational cargo craft capable of returning significant payloads to Earth intact.
If the flight is successful, the next Cygnus mission - tentatively set for December - will be the first of eight operational cargo deliveries under a $1.9 billion resupply contract with NASA.