NASA’s Space Launch System (SLS) heavy-lift rocket remains on track for a first launch in December 2017 despite warnings in a recent Government Accountability Office (GAO) about cost and schedule problems, the program’s manager said Friday.
Speaking at the 17th Annual International Mars Society Convention in Houston, SLS program manager Todd May said the program was at or ahead of schedule as it works through a series of critical design reviews (CDRs) for the SLS and its major systems. “We said four years ago we’d be at critical design review on the core [stage] this November. I’m glad to report that we actually completed that last month,” he said, a statement that generated an impromptu round of applause from the couple hundred attendees of the session. The CDR on the booster stages was completed just this week, he said, and the CDR for the full SLS is on track for the spring of 2015.
“Things are going pretty well. As far as the critical path, we’ve still got three to five months of slack” on the date the core stage is due to be delivered to the Stennis Space Center in Mississippi for testing, he said. “We’re just clicking off milestones.”
That rosy assessment stands in contrast to a report issued last month by the GAO that warned of cost and schedule risks to the program. “The SLS program office calculated the risk associated with insufficient funding through 2017 as having a 90 percent likelihood of occurrence,” the report stated, “furthermore, it indicated the insufficient budget could push the planned December 2017 launch date out 6 months and add some $400 million to the overall cost of SLS development.”
Asked about the GAO report, May suggested that conclusion was based on information that was now out of date. “They saw some things a couple of years ago. Some of the data is now obsolete,” he said. Specifically, he said the funding SLS received in fiscal year 2014, and what it expects to get in 2015 when the appropriations process is completed, is above the original request. In 2014, the administration requested $1.385 billion for SLS, but received $1.6 billion. In 2015, the administration requested $1.38 billion, but House and Senate version of appropriations bills offer $1.6 and 1.7 billion, respectively, for SLS.
That additional funding, May said, has mitigated the risk identified in the GAO report, provided that level of support continues. “If you don’t receive the appropriated levels, you could see challenges,” he said.
As for schedule risks, May said Monte Carlo risk models widely used in such analyses aren’t always accurate. “To me, they don’t change a basic program management tenet, which is to hurry every chance you get,” he said. That approach, he said, has worked for planetary exploration missions that have to launch within narrow windows. “They don’t pay attention to those things. They hurry every chance they get. So far, that’s paying off for us.”