It’s hard to believe that this was said with a straight face:
“The review had to be incredibly detailed, so our plans for vehicle integration, flight software, test, verification and operations will result in a safe, affordable and sustainable vehicle design,” said Todd May, manager of the SLS Program at NASA’s Marshall Space Flight Center in Huntsville, Ala.
Really? Affordable? And if it’s not affordable it’s not sustainable.
As for safety, here’s what I wrote in the book:
It should be noted that NASA currently plans only two flights for the SLS—one in 2017 to demonstrate the 70-ton capability, and one with a crew in 2021, to…somewhere. They have said that, when operational, it may only fly every couple of years. What are the implications of that, in terms of both cost and safety?
Cost wise, it means that each flight will cost several billion dollars, at least for those first two flights. If, once in operation, it has a two- or three-billion-dollar annual budget (a reasonable guess based on Shuttle history), and it only flies every couple of years, that means that each subsequent flight will cost anywhere from four to six billion dollars.
From a safety standpoint, it means that its operating tempo will be far too slow, and its flights far too infrequent, to safely and reliably operate the system. The launch crews will be sitting around for months with little to do, and by the time the next launch occurs they’ll have forgotten how to do it, if they haven’t left from sheer boredom to seek another job.
As a last-ditch effort to try to preserve the Shuttle in 2010, some suggested that it be maintained until we had a replacement, but to fly it only once per year to save money. The worst part of such a proposal would have been the degree to which the system would have been even less safe, given that it was designed for a launch rate of at least four flights per year. It was unsafe to fly it too often (as NASA learned in the 80s as it ramped up the flight rate before Challenger), and it would be equally so to fly it too rarely.
NASA’s nominal plans for SLS compound this folly, which is magnified by the fact that both internal NASA studies and independent industry ones have demonstrated that there is no need for such a vehicle to explore beyond earth orbit (existing launchers could do that job just fine, with orbital mating and operations), and it is eating up all the funding for systems, such as landers and orbital propellant storage facilities, that are necessary. All of this is just more indication that actually accomplishing things in space is the lowest priority for Congress (and unfortunately, the space agency itself, otherwise, the administrator would be more honest with the appropriators on the Hill).
But this PDR will be hailed by supporters nonetheless.