Wednesday, September 19, 2012
SLS / Orion
Orion and SLS: Where Are They Now?
By Amy Teitel
An artist’s concept of SLS lifting Orion off the launch pad. We might see this sometime in 2017. Image Credit: NASA
It’s been a little over a year since NASA announced its intention to build the Space Launch System or SLS, the rocket that will be bigger and more powerful than the Saturn V. It’s payload is set to be the Orion Multi-Purpose Crew Vehicle, the Apollo-inspired capsule that is slated to take men to the Moon, Mars, and asteroids at some still-undefined point in the future. Last Wednesday, the Republican Subcommittee on Space and Aeronautics held a hearing to examine ongoing developments of Orion and SLS. The word from NASA is that both projects are moving forward. But schedules are starting to slip, and things will only get worse if the agency faces further budget cuts.
Testifying at the September 12 hearing were Cleon Lacefield, Vice President and Orion Program Manager from Lockheed Martin; Boeing Space Exploration Vice President and SLS Stages Program Manager Jim Chilton; NASA Deputy Associate Administrator for Exploration Systems Development Daniel L. Dumbacher; and Matt Mountain, Director of the Space Telescope Science Institute.
The overall feeling, as Dumbacher vocalized it, is that SLS and Orion “fit well within a broader U.S. launch strategy” and remain “fundamental building blocks in a capability-based architecture designed for long-term human exploration of our solar system.”
NASA, Dumbacher said, has made steady progress. The agency completed an integrated Systems Requirements Review in February for the full-up Orion, SLS, and related ground systems. On July 2, the first flight test crew module of Orion arrived at KSC for assembly and integration. The spacecraft has gone completed acoustic and vibration tests, water impact tests, and in various configurations of parachute tests. The new Launch Abort System has been tested, as has a new navigation and docking system called STORRM – this one was done in orbit on STS-134. Its state-of-the art heat shield is under construction, and the avionics and software systems are still undergoing tests.
A mockup of the Orion capsule. Photo Credit: NASA
This is all building towards Orion’s first unmanned flight that will launch not on an SLS but a Delta IV. Still scheduled for sometime in 2014, Exploration Flight Test-1 (EFT-1) will be a two-orbit mission that will see the spacecraft reenter the atmosphere faster than any mission since Apollo crews returned from the Moon, testing the heat shield to a maximum reentry temperature of 2,000 degrees. It’s a pathfinding mission that will give NASA critical vehicle performance data needed to confirm detailed design of the Orion spacecraft to fly in 2017 on Exploration Mission-1 (EM-1).
To keep both these flights on schedule, NASA has streamlined Orion program management and incorporated “proven commercial practices to ensure our ability to work within constrained NASA budgets while keeping the program moving forward,” said Lacefield. He added that it’s a tenuous balance. “It remains critically important that Congress maintain FY2013 funding at the current level to ensure timely and successful implementation of EFT-1 in 2014.”
As for Orion’s eventual launch vehicle, SLS seems to be mirroring its future spacecraft’s progress. After the initial announcement last September 14, it took NASA just three months to get all contractors lined up; by the end of 2011 every element of SLS was organized.
The Boeing-built Core Stage has successfully completed initial reviews, and all hands are “on deck to achieve the aggressive schedule,” said Dumbacher. The 5-segment solid rocket motor is on track for a test firing next May. Booster and vehicle avionics and software are still pending testing. The 15 RS-25D liquid hydrogen/liquid oxygen engines recovered from the shuttle program are ready for integration and testing with the core stage when it’s completed. Unfortunately, this one piece of the SLS is the one new piece; everywhere else, technical elements and proven approaches from other programs have been implemented. The core stage is a critical piece, “the backbone on which the other elements depend,” said Chilton.
At the end of the day, it looks like the major challenges to both Orion and SLS aren’t technical, they’re management problems. The real challenge is maintaining program stability as Dumbacher described it, “acquiring the Orion and SLS systems so that the next elements of the Exploration enterprise can be developed.” There are also bound to be hardware development, manufacturing, and supply chain challenges as both programs move towards launch dates, though NASA says its working diligently with its contractors to find these potential problems early.
A comparison of the SLS with past and present NASA launch systems. Image Credit: NASA
The budget is also a problem just waiting to rear its head. As Chilton pointed out, a flat budget profile is atypical for development programs. It’s created a unique set of challenges that threaten to hamper particularly SLS throughout its evolutionary process. Mountain echoed this warning, citing the prevention of temporary budget changes and recognition that NASA can only develop one new SLS element at a time will be crucial to the program’s success.
As for what will come after the initial unmanned flights in 2014 and 2027, that’s also still in the air. So far, the first manned flight has already slipped. Originally scheduled for sometime in 2019, it’s been pushed back to 2021; there was no mention of whether that first manned flight will still be a circumlunar flight or not.
The paths these programs take will depends on what NASA decides is more important: the ability to launch heavier payloads into low Earth orbit or the capacity to send crews beyond Earth orbit. The final thing that will secure SLS’ success, says Mountain, is a commitment to decisions once they’re made. Unfortunately, recent history is filled with unfulfilled promises in space.
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