Suffredini pointed out that ISS operations require 15-17 flights per year and “then sprinkle in EVAs, it’s hard to find time to do research.” EVA refers to extravehicular activity, or spacewalks. NASA has a goal of performing 35 hours of research per week, but the current average is 26.13 hours. He is trying to find ways to “buy back crew time” and looking forward to the era of commercial crew when the typical ISS crew complement will be seven instead of six.
This means that rather than doubling productivity, adding a crew member would increase it by a factor of two and a half. And adding two would increase it by a factor of four (assuming forty-hour weeks — not sure why NASA only has a target of thirty five, or why it’s not even higher, given that they don’t have a hell of a lot else to do up there).
As a way of plugging my upcoming book:
To get back to the bizarre (at least that’s how it would appear to a Martian) behavior with respect to ISS, what is it worth? Of what value is it to have people aboard? We have spent about a hundred billion dollars on it over almost three decades. We are continuing to spend two or three billion a year on it, depending on how one keeps the books. For that, if the purpose is research, we are getting about one person-year of such (simply maintaining the facility takes a sufficient amount of available crew time that on average, only one person is doing actual research at any given time). That would imply that we think that a person-year of orbital research is worth two or three gigabucks.
What is the constraint on crew size? For now, not volume, and not the life support system – I don’t know how many ultimately it could handle, but we know that there is not currently a larger crew because of NASA’s lifeboat requirement, and there has to be a Soyuz (which can return three) for each three people on the station. If what they were doing was really important, they’d do what they do at Scott-Amundsen, and live without. After all, as suggested earlier, just adding two researchers would immediately triple the productivity of the facility. That’s not to say that they couldn’t be continuing to improve the safety, and develop a larger life boat eventually (the Dragon is probably very close to being able to serve as one now, since it doesn’t need a launch abort system for that role), but their unwillingness to risk crew now is indicative of how unimportant whatever science being done on the station really is.
Actually, I should update the book to reflect the new numbers.
Even with the concerns about Dragon issues, I’d bet that there are plenty of people who’d be happy to trust it as a lifeboat right now, though they really should get the new docking adapter up there ASAP. That is really on the critical path to expanding capability. Of course, if they were really serious, they’d do without a lifeboat or ambulance, as Scott-Amundsen does in the winter, and just add crew. I guess Antarctic research is more important than orbital research.