Over on twitter today, Jeff Foust (@jeff_foust) reported on a new reusable rocket project that will be starting in DARPA’s Tactical Technology Office (TTO) next month. Rumor has it that Jess Sponable, the former Program Manager for the DC-X project, and long-time advocate for reusable launch vehicles, will be leading this new project.
According to Jeff’s twitter notes from Pam Melroy (DARPA TTO’s Deputy Director) talk at SPACE 2013:
- The goal is for a reusable first stage that can fly 10 times in 10 days, at speeds up to Mach 10
- The first stage would be sized big enough that with an expendable upper stage, it could place 1-4klbs in LEO
- The target launch price (not sure if this is for the 1st stage only or for both stages) is $5M/launch
- While the concept art showed many winged vehicles, they’re open to other approaches, so long as they can do staging at Mach 10
- There will be an Industry Day for XS-1 sometime early next month–this is an opportunity for interested parties to learn more about the program, and ask questions of the Program Manager and Contract Management team there at DARPA
- A Broad Area Announcement (BAA–a form of solicitation DARPA uses for most programs) is planned to be out sometime next month
That’s all Jeff shared via twitter, but I wouldn’t be surprised if he did a blog post with more details tonight on Space Politics or over on his NewSpace Journal blog. I’ll link to them if he does. I also created a discussion thread over on NASASpaceflight.com for this topic.
A couple of thoughts I mentioned there:
- Mach 10 is a pretty high staging number. Most of the RTLS First Stage concepts I discussed here on Selenian Boondocks optimize at staging numbers in the Mach 3-5 range. In fact, other than a hypersonic flyback stage (which I doubt is the best choice technically or financially), the only approaches that would yield anything near optimum performance with a Mach 10 staging requirement are the two Lift-Assisted Boostback options I discussed in my Boostback post. Knowing Jess, I’m sure this requirement is based on some sort of analysis, so I’d like to see where it came from. I worry that by picking such a high staging speed, he may be eliminating many promising alternative approaches. Though DARPA TTO has had a strong interest in hypersonic vehicles for a long time, so it could just be pressure from inside the office. Hopefully this still allows for a range of creative options. I guess it might be possible to do this boostback style with a slightly-less optimized VTVL vehicle of some sort.
- A reusable first stage with an expendable upper stage that can put 1-4klb into LEO could likely put 300-500kg into LEO with a reusable upper stage. This was in an interesting sweet spot that I was discussing with Jeff Greason at Space Access a few years ago.
- It’s important to remember that historically, most DARPA missions get canceled before flight. Some of this may be due to the high planned turnover at DARPA–program managers get hired for something like 3yr stints, after which time they go back to industry or elsewhere in government. The good news is if they can make enough progress, a lot of times technology from a mission that gets canceled can get infused into a newer mission with slight different focus (like the FREND robotic arms from the cancelled SUMO project getting baselined into the Phoenix program). I’m still super-excited that Jess was able to talk DARPA into funding something like this, and he does have a good shot if he has adequate funding. I just don’t want people acting as though this program has already succeeded. I sure as heck hope it does, and Jess is a sharp program manager with experience running projects like this before, so I’m hopeful. It just seems like cool space ideas get jinxed by premature overoptimism.
So, as I said, I’m really excited to see how this turns out. I wish I could attend the Industry Day unfortunately, but since Altius isn’t really a rocket company anymore, justify the travel costs may not be feasible. But if someone else can go, I’d love to get a report.
And good luck to DARPA!
[Update #1 2:59pm MDT: Over on my NASASpaceflight.com thread, yg1968 just posted some slides from the presentation, and a link to a video of the presentation–the relevant part starts just after the 20min mark, and confirms my concerns about them conflating hypersonic testing and low-cost access to space.]
[Update #2 3:05pm MDT: Jeff Foust just did a Space News article on the topic.]
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