I typically don’t get a chance to listen in on the Space Show too often. I work long enough hours that when I get home I typically don’t have a 1.5-2hr chunk of time where I can set aside for personal time. However there was a talk this week about orbital propellant depots given by Dallas Bienhoff of Boeing that I was planning on trying to find a way to listen to. Alas, it turns out that it was scheduled at the exact same time as a dentists appointment I had previously scheduled, so I had to download the archive and listen to it at home. I’ve met Dallas at a few space conferences over the years, including the ACES conference out at NASA Ames in October 2005. When it comes to orbital propellant depots, he’s one of the most knowledgeable people I know, so the show ended up being very interesting.
A lot of what Dallas said mirrors some of the points I’ve been making here. That propellant depots could greatly enhance the current lunar plan. That they could provide huge markets for commercial orbital flight. That NASA isn’t going to develop one of these on their own. Etc. I’d just like to comment on a few of the things he said that got me thinking.
Dallas presented a paper at STAIF a few weeks back discussing the implications of a commercial propellant depot for NASA’s ESAS architecture. He found that by using orbital propellant transfer, the amount of surface cargo that could be delivered in a single flight could be more than tripled. This would be enough to bring a Sundancer module, or a ISS derived module down to the lunar surface, even at the same time as bringing crew down.
The market implications are even more impressive. Just to support 2 NASA lunar flights per year, there would be demand for nearly 40 Falcon IX sized flights. When you compare this with the current global launch market, you can see how important this market could be. It’s large enough that it could possibly provide flight rates high enough to help close the business case for one or more orbital RLV companies.
There has been a lot of discussion claiming that orbital propellant depots only make financial sense if SpaceX is successful with their Falcon IX. However at different points in his interview, Dallas clarified several things. First, he clarified that the reason he used SpaceX numbers so much was because they were publicly available information that he couldn’t get in trouble for talking about. Second, in light of the high projected flight demand (40+ launches per year), a listener asked if Boeing or Lockheed’s prices could drop far enough for Delta or Atlas to close the business case. Dallas skirted the question, saying that the idea was possible, and that it was under investigation. If the numbers I’ve heard for human rated Atlas flights are any indication, then there is a real chance that Atlas could be a contender. Quite frankly, with a market this big, it’s almost guaranteed that there will be more than one supplier. Possibly even more than two or three. Third, he also discussed the possibility of buying foreign launches. He brought up the launch inclination difficulties associated with Russian launch sites, but what with Soyuz expected to start flying out of Kourou next year, that could change substantially. With foreign providers, there will be real competition going on, and the prices will likely be kept low enough, even without SpaceX, to make such a venture worthwhile. If SpaceX succeeds, all the better.
One thing that came to mind during his discussion of using foreign propellant launches was the fact that an international standard propellant transfer interface could be very useful at some point in the future. If someone like MDA of Canada (or any of a number of European or Asian companies) were to come up with a working, standardized interface design for propellant transfer, it wouldn’t be ITAR restricted, and would likely greatly facilitate the use of internationally launched propellant tankers. I imagine such standards already exist in other markets like oil transport and such. I wonder if a prize for coming up with such a specification might be useful?
Dallas also talked about the concept of anchor tenants, and how NASA could possibly make things drastically easier by acting as one. Unfortunately, Dallas came to the same conclusion as I did–that while writing NASA entirely off a customer is probably premature, they haven’t proven themselves to be very reliable or stable customers in the past. Basing your business plan on them buying propellant from you is a recipe for disaster. He did mention one possible alternative, which was interesting: Bigelow Aerospace. Now, that’s still a bit premature, seeing as how they haven’t yet orbitted their first manned space station, but they have expressed a lot of interest in cislunar transportation, lunar cyclers, and most recently landing whole lunar bases in a single flight. All of these could benefit immensely from orbital propellant transfer. So, once Bigelow gets his current projects brought to market, working with him might make a lot of sense.
Anyhow, I think Dallas painted a fairly useful picture of how close this technology is to primetime. There are probably ways to make a 1st generation propellant depot even simpler than he outlined, but I think he made my case that this is a near-term technology that can have massive impacts on commercial space transportation.
Listen to the whole thing.