Orbital ATK’s first unmanned Cygnus cargo ship since the loss of the ORB-3 mission last year is nearly ready for an early December return-to-flight to deliver over 7,700 pounds of supplies, equipment, and experiments to the International Space Station (ISS) for NASA. The OA-4 mission is scheduled to launch Dec. 3, courtesy of a United Launch Alliance (ULA) Atlas-V 401 rocket, and this week engineers in the Space Station Processing Facility at NASA’s Kennedy Space Center in Florida finished packing the pressurized portion of the spacecraft for the 17,500 mph trip to the $100 billion international orbital research outpost.
Workers had to lift the spacecraft’s Pressurized Cargo Module (PCM) and rotate it upright to join it to the spacecraft’s second critical piece of hardware, the power-producing Service Module (SM)—the “brain” of Cygnus that holds the spacecraft’s avionics, electrical, communication, propulsion system, and instrumentation to steer in space.
The spacecraft as a whole is an enhanced version of the original, featuring an extended PCM, a lighter CM, and new lightweight Ultraflex solar arrays, upgrades which will enable the new Cygnus to fly nearly as much weight as the last three Cygnus missions combined.
The OA-4 resupply mission will come over a year after Orbital ATK’s 133-foot-tall Antares rocket exploded spectacularly just six seconds after liftoff on Oct. 28, 2014, carrying the company’s Cygnus on its third ISS resupply mission under a $1.9 billion Commercial Resupply Services (CRS) contract with NASA. Signed in December 2008, the agreement requires the Dulles, Va.-based company to fly eight dedicated Cygnus missions to the ISS by 2016 to deliver a total of 44,000 pounds of payloads and other items for NASA.
The contract has since since been extended, for obvious reasons, and NASA has already given Orbital ATK two additional missions under that same contract as well, missions OA-9e and OA-10e, giving Cygnus 10 flights under the CRS-1 contract instead of the original eight.
However, the increased capability of the ULA Atlas-V compared to the Orbital ATK Antares means ULA can haul 35 percent more cargo to orbit with Cygnus, which would have allowed Orbital ATK to fulfill their original CRS-1 contract in seven flights instead of eight. Now, with the contract extended to 10 flights, it is expected that Orbital ATK will only really need nine, with the 10th Cygnus CRS-1 contract flight optional depending on the needs of the ISS.
NASA signed two CRS contracts; the other was signed with SpaceX for the same ISS resupply services. This summer a SpaceX Falcon-9 also exploded with its Dragon capsule packed with thousands of pounds of ISS cargo, leaving the United States again unable to reach the ISS on its own. SpaceX also received an extension from NASA for their CRS-1 contract, with several new resupply missions added to the manifest.
The loss of ORB-3 last year was eventually blamed on a turbopump-related failure in one of the two Aerojet Rocketdyne AJ-26 stage one main engines the Antares employed. Aerojet, however, has rebutted this cause and instead puts the blame on improper handling. Orbital ATK has since replaced the AJ-26 engines on the Antares 130 variant, and has instead purchased Russian RD-181 engines from NPO Energomash for the more powerful Antares 230 variant. The greater performance of the upgraded Antares 230 will permit Cygnus to deliver over 20 percent more cargo—some 15,000 pounds—to low-Earth orbit.
The first set of the rocket’s new RD-181 engines arrived at Orbital ATK’s Antares launch site at the Mid-Atlantic Regional Spaceport on NASA’s Wallops Flight Facility in Virginia last July, and the first set of new engines have already been integrated with the rocket’s modified core stage. A second set of engines for another Antares was expected to be delivered this fall, and a 29-second static test fire of the upgraded Antares first stage with the new AJ-26 engines is on track for December or January.
“The integration of our first launch vehicle is well underway and we are solidly on track to resume flying Antares in 2016,” said Mike Pinkston, Vice President and General Manager of Orbital ATK’s Antares Program. “The RD-181 provides more thrust and higher specific impulse than the AJ-26. This, combined with the extra power of the Castor 30XL upper stage, will greatly increase the payload capacity of Antares, enabling Orbital ATK to achieve the cargo requirements of their CRS contact with NASA in fewer flights.”
The Antares launch pad sustained damage from the ORB-3 explosion as well, and has since been completely repaired. The future of Antares and Cygnus, however, is not certain. NASA is expected to announce Nov. 5 whether Orbital ATK receives another multi-billion dollar CRS contract (CRS-2) or not, as there are several companies in the running. If Cygnus is not contracted for the next round of NASA ISS resupply contracts then the Wallops launch site, and Antares rocket, may remain quiet for much longer than just the last year.
In the meantime Orbital ATK will need ULA for another Atlas-V rocket to launch Cygnus a second time early next year, which will supplement two or three Antares-launched missions to the ISS in 2016, with the first expected next spring.
“With OA-4 set to launch in December and at least three additional missions to the ISS planned in 2016, we remain solidly on schedule to meet our CRS cargo requirements for NASA,” said Frank Culbertson, president of Orbital ATK’s Space Systems Group and former NASA space shuttle/ISS astronaut. “Our team’s performance in meeting milestones on an accelerated timeline demonstrates the company’s flexibility and responsiveness to customer needs. If all goes as planned, on Dec. 3, space watchers new and seasoned can thrill to seeing a unique, ‘two-of-its-kind’ launch, as an Atlas-V rocket lofts a Cygnus cargo ship to orbit.”
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