Orbital ATK’s Cygnus spacecraft is set to return to International Space Station (ISS) resupply duties in December, hitching a ride on an Atlas V, prior to resuming operations with the modified Antares rocket in 2016. Cygnus has been out of action since the CRS-3/OrB-3 failure that occurred in October 2014 – with the full investigation results yet to be released to the public.
The return of Cygnus resupply missions will prove to be a welcome boost for the ISS, following an unprecedented loss of three Visiting Vehicle missions in close succession, including the OrB-3 Cygnus that was lost shortly after launch.
The loss of the CRS-3/OrB-3 Cygnus was followed by the failure of the Russian Progress M-27M spacecraft and the destruction of the CRS-7 Dragon when SpaceX’s Falcon 9 v1.1 failed during ascent.
The dramatic failure of the Antares rocket T+14 seconds into ascent from its Wallops pad was the result of a “probable turbopump-related failure” in one of the two Aerojet Rocketdyne AJ-26 main engines.
The initial investigation into the failure was conducted earlier this year.
“The Antares Orb-3 Accident Investigation Board (AIB) sent its final draft report to the FAA (Federal Aviation Administration) on March 30 for review,” noted L2 information in March. “They will have the first review of it per commercial launch regulations. That review is expected to take no more than a week.”
However, alleged disagreements over the ultimate root cause that resulted in the turbopump failure required further evaluation.
“The AJ-26 engine failure caused that rocket to crash. The investigation focused on ruling out Foreign Object Debris (FOD),” L2 notes added in May. “Information is pointing to an internal engine fault and an issue on a turbo pump, but that investigation is still ongoing.”
The latest conclusions were recently provided to the FAA, although a projected release date of the results to the public has slipped on a weekly basis since earlier this year.
Ultimately, the troubled AJ-26 engine will no longer be used on Antares missions, with Orbital ATK opting to switch to a different engine – a decision made early into the post-failure recovery process.
The replacement engine – on what will be known as the Antares 200 – will be the RD-193, or RD-181 as they are known when labelled under their “foreign export” designation.
The first of those new engines have already been shipped to the United States from Russia under what is believed to be a $1 billion deal between Orbital ATK and Energiya/Energomash. The deal is understood to include the purchase of 60 engines.
During a conference call with investors this week, ATK Orbital noted it had successfully concluded acceptance testing on the new engine, allowing for a projected return to flight for the Antares rocket in 2016.
Progress on the upgraded Antares has proceeded well, with NASA’s Launch Services Program (LSP) noting it had supported the completion of the Critical Design Review (CDR) earlier this year.
“LSP Propulsion Engineering supported the Antares 230/330 hydraulics CDR, providing comments to CRS to improve the robustness and operability of the system,” per L2 notes.
“LSP Vehicle Systems Engineering, Propulsion Engineering, Stress, Avionics and SMA (Safety and Mission Assurance) participated in the Antares Stage 1 CDR for the modifications necessary to integrate the RD-181 engine at both the 230 and 330 thrust levels.”
With the Wallops facility at the Mid-Atlantic Regional Spaceport (MARS) now returning to an operational status following the physical damage caused by the OrB-3 failure, the first major milestone for Antares’ return will be a hot fire test – which will take place either at the end of this year or early in 2016.
The conference call noted all new Antares hardware is expected to be on site by mid-August.
While preparations are made to return Antares to launch operations, Cygnus will be back in action before the year is out, hitching a ride on the United Launch Alliance (ULA) Atlas V – specifically AV-061 – for the CRS-4/OrB-4 mission.
The launch will take place from Space Launch Complex -41 (SLC-41) at Cape Canaveral.
The interim solution was arranged between the two companies to ensure ATK Orbital continued to fulfill its obligations per the Commercial Resupply Services (CRS) contract with NASA.
The return of Cygnus is expected to take place in December, with the current launch date showing on Flight Planning documentation (L2) as December 3, with Cygnus arriving at the ISS for berthing on December 6 for a 60 day mission.
Key processing milestones are expected to pick up the pace this month, with the OrB-4 Pressurized Cargo Module (PCM) – built by Thales Alenia Space in Italy – set to arrive in the United States as soon as this weekend.
It is then scheduled to be trucked to the Kennedy Space Center (KSC) early next week.
Processing will involve integration with the Service Module to “create” the Cygnus spacecraft, prior to its checkout, payload installation and fairing encapsulation. The Atlas V will await the spacecraft’s arrival for mating at her SLC-41 complex.
There remains the possibility the return of the Cygnus may also – depending on processing flow schedules – be pushed up by a number of weeks.
NASA managers noted this could become a potential request during comments made shortly after the failure of the CRS-7 Dragon mission.
However, ISS managers will likely wait for SpaceX’s updated manifest, when it will reveal its own return to flight plans in the coming days/weeks – which may include when the next Dragon will be launched to the ISS.
SpaceX’s updated schedule is understood to be eyeing a tightly packed salvo of launches, potentially opening with a Return To Flight mission from Vandenberg in October – per the latest source information in L2.
Both SpaceX and ATK Orbital have a series of resupply runs to conduct under their ongoing CRS contracts.
During Thursday’s teleconference, ATK Orbital noted it now has two additional missions that will be added to its ISS cargo resupply contract. These missions are being scheduled to occur between mid-2017 and early 2018.
NASA will then move into the CRS2 phase, aimed at resupplying the ISS through what is now an extended lifetime on orbit.
(Images: via L2’s Antares/Cygnus Section – Containing presentations, videos, a vast set of unreleased hi-res images, interactive high level updates and more, with additional images – including the new Atlas V with ORB-4 Cygnus via L2 artist Nathan Koga. Other images via Orbital and NASA).
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