Upgraded Antares And Atlas V To Complete Orbital Crs Missions
The company's go-forward plans include using ULA's Atlas V launch vehicle instead of Antares, and its upgraded Antares launcher to complete the Commercial Resupply Service (CRS) contract with NASA.
For this, Orbital has contracted with United Launch Alliance for an Atlas V launch of Orbital's Cygnus cargo spacecraft from Cape Canaveral, Florida, in the fourth quarter of 2015, with an option for a second Atlas V launch in 2016 if needed.
Orbital says Atlas rocket's greater lift capacity will allow Cygnus to carry nearly 35% more cargo to the ISS than previously planned for CRS missions in 2015.
The company says its primary objective is to fulfill its commitment to NASA for ISS cargo deliveries with high levels of safety and reliability and minimum disruption to schedules.
The second plan is to accelerate the introduction of a new main propulsion system for the Antares rocket. Orbital has scheduled three additional CRS launches in the first, second and fourth quarters of 2016 using the upgraded vehicle. The greater payload performance of the upgraded Antares will permit Cygnus spacecraft on each of these missions to deliver over 20% more cargo than in prior plans. With necessary supplier contracts now in place, the first new propulsion systems are expected to arrive at the Antares final assembly facility at Wallops Island, Virginia in mid-2015 to begin vehicle integration and testing.
The flexibility of Orbital's Cygnus cargo spacecraft to accommodate heavier cargo loads, together with the greater lift capacity of the Atlas V and upgraded Antares vehicles, will allow the company to complete all currently contracted ISS deliveries in four missions instead of the five previously planned flights over the next two years.
These plans are expected to allow Orbital to accomplish all remaining cargo deliveries by the end of 2016 with no cost increase to NASA.
Under a 1.9 billion CRS contract with NASA, Orbital was to use Antares and Cygnus to deliver up to 44,000 pounds (20,000 kilograms) of cargo to ISS through late 2016. The Oct 28 mission was second of the eight missions planned.
Preliminary evidence and analysis conducted pointed to a probable turbopump-related failure in one of the two Aerojet Rocketdyne AJ26 stage one main engines. As a result, the use of these engines for the Antares vehicle likely will be discontinued.
The AJ-26 is a Aerojet modified Kuznetsov NK-33 engine manufactured nearly fifty years ago by the Soviet Union to power its failed giant N-1 moon rocket. After four consecutive launch failures, the project was cancelled.
Meanwhile, the Mid-Atlantic Regional Spaceport (MARS) has assessed the clean-up, repair and reconstruction work necessary to return the Wallops launch complex (were the Antares disintegrated) to operational status. Current plans call for repairs to be substantially completed by the fall of 2015, with recertification taking place before year end.
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