Unfunded Human-rating Study Examined Atlas 5 Failure Modes
LAS CRUCES, N.M. — Completion of a yearlong joint study with NASA has brought the( ) Atlas 5 rocket a step closer to being certified to launch crew-carrying vehicles to the international space station starting later this decade, the space agency said.
NASA announced Oct. 15 that ULA had completed its work on an unfunded Space Act Agreement during which it examined, among other things, possible failure modes for the proven Atlas 5. Denver-based ULA, a Boeing-Lockheed Martin joint venture, fulfilled the fifth and final milestone of the agreement, awarded in 2011 as part of NASA’s Commercial Crew Development (CCDev) 2 program, in August.
Recipients of unfunded Space Act Agreements get access to NASA infrastructure and expertise but no money changes hands.
Data from the ULA study are critical to efforts by Boeing and Sierra Nevada Corp. to field commercial vehicles capable of ferrying astronauts to and from the space station. Houston-based Boeing Space Exploration and Sierra Nevada Space Systems of Louisville, Colo., have selected the Atlas 5 as the launcher for their proposed vehicles, which are being developed under funded Space Act Agreements awarded by NASA in August.
If either company ultimately wins a contract to transport astronaut crews, Atlas 5 will have to be certified by NASA as safe for human transport prior to 2017, the agency’s notional date for the first privately operated astronaut flight.
A third competitor in NASA’s Commercial Crew Program, Space Exploration Technologies Corp. () of Hawthorne, Calif., would launch its proposed crew capsule aboard its Falcon 9 rocket, which has made four successful flights to date. SpaceX is working on a crew-carrying variant of its Dragon cargo capsule, which has made two trips to the space station to date under a separate NASA-funded program.
NASA is spending a combined $1.2 billion on the SpaceX, Boeing and Sierra Nevada concepts under the third and final development round of the Commercial Crew Program. At the end of the 21-month effort, the agency intends to select at least one company to ferry space station crews on a commercial basis.
ULA’s study work was focused on understanding “all the different ways the Atlas 5 could possibly fail,” George Sowers, ULA’s vice president of human spaceflight, said in an Oct. 17 interview here. “This is all data that feeds into our emergency detection system and will eventually support certification.”
The emergency detection system, designed to detect crew-threatening launch anomalies, is critical to fielding a human-rated version of the Atlas 5. ULA won a $6.7 million Space Act Agreement for design work on the system in 2010.
Although the Atlas 5 is built and operated by ULA, it is Boeing or Sierra Nevada that would bear responsibility for securing a NASA safety certification for the vehicle. Rather than certify elements of a crew transportation system piecemeal, NASA says it will certify only a complete system that includes both a launcher and a crew vehicle.
NASA, meanwhile, is planning to award between two and four Certification Products Contracts in February. These contracts, which would be worth up to $10 million each, will allow NASA to examine certain elements of proposed crew transportation systems and determine whether the designs meet agency safety standards.
Besides work on the emergency detection system, ULA’s CCDev 2 Space Act Agreement also set design requirements for the company’s planned dual-engine Centaur upper stage; explored the technical challenges of certifying the Atlas 5 to NASA’s human-rating requirements; and settled on design approaches for modifying Launch Complex 41 at the Cape Canaveral Air Force Station in Florida to support the Boeing and Sierra Nevada crew vehicles.
Following the retirement of the space shuttle fleet in July 2011, NASA has relied on the Russian government to fly its astronauts to the space station. Rides on the Russian Soyuz system currently cost the U.S. space agency about $65 million a seat.