NASA has been fibbing to Congress about the SLS and propellant depots.

Bottom lines:

NEA Mission Observations – Mixed Fleet

* Costs $10s of billions less through 2030 over alternate HLLV/SEP-based architecture approaches
– Only $10B more than all Falcon Heavy approach
* Fits within conservative exploration budget through 2030 with extended ISS and budget cuts while allowing 3-4 NEA missions
* Breaking costs into smaller, less-monolithic amounts allows great flexibility in meeting smaller and changing budget profiles
* Allows first mission to NEA in 2024, potentially several years earlier than HLLV/SEP-based approaches, meeting President’s deadline and actual availability of NEA 2008EV5
* Launch capacity not much of an issue with two suppliers
– Availability risk also improved
* Use of two CLVs, similar to COTS, should reduce cost and risk through competition
* Integration of large CPS stage with multiple vehicles could reduce commonality and add complexity

Lunar Mission Observations -RP Depot/CPS

* Costs $10s of billions less through 2030 over alternate HLLV/SEP-based architecture approaches
– Only $2B more than LO2/LH2 Depot approach
* Fits within conservative exploration budget through 2030 with extended ISS and budget cuts while allowing 4-8 lunar missions
* Breaking costs into smaller, less-monolithic amounts allows great flexibility in meeting smaller and changing budget profiles
* Allows first lunar mission to in 2024, potentially several years earlier than HLLV-based approaches
* Launch capacity does not appear to be a major issue
* Dependence on a single CLV and provider likely unacceptable
* Integration of large CPS stage with small-diameter Falcon easier due to smaller stage size
* Integration of lunar lander on Falcon limits design options
* RP-based depot/CPS provides slightly higher LCC for lunar missions with lower risk

Just as I and others have been saying for years. But it doesn’t “save or create” the jobs in the right places.

[Update mid morning]

I’m looking through the briefing now. They have an interesting design reference mission to an asteroid that appears to use solar electric propulsion to get the departure propellant out to EML-1. If you look at the sandpile for the reference HEFT DRM-1, on chart 10, you can see how much the budget would be reduced if you forgo the development of the HLLV. It looks like about a third of the total, and doesn’t get you to the asteroid until eighteen years from now. Going with the depot approach saves tens of billions and accelerates the mission by half a decade.

For the lunar mission, they don’t do it they way I would — they have a LEO depot, and then do it Apollo style from there. I’d put a depot at EML-1, and send the lander up separately on a slow boat, to minimize the high-impulse delta vee necessary for the trip. Ideally, you’d have multiple depots and reusable space systems throughout the architecture. But the way they’ve done it gets the cost down to sixty billion through 2030 (presumably current-year dollars), with a lunar landing in 2024l with another mission every two years. So by my count, we get four lunar missions at a cost of fifteen billion each. Still very expensive, but a lot cheaper than with the SLS, and sooner. If you use Delta IV-H instead of Falcon Heavy, the price goes to $75B. Most likely one would use a mixed fleet for resiliency.

These architectures look an awful lot like the kinds we did at Boeing seven years ago for CE&I, that Mike Griffin never even looked at. All of their cost assumptions appear to be very conservative. And they probably don’t take into account the fact that you’d launch the hardware dry, which reduces structural weight.

[Update a few minutes later]

Wow. The cost comparison charts are devastating. In Chart 48, the heavy architecture is over twice as much in DDT&E as any of the others. If Dana was chairman, this would be the subject of a hearing, but he’s not, so it won’t be. But he can certainly issue a press release. I’m assuming that this is the briefing that he was asking for last month.

[Early afternoon update]

In finishing the briefing, I see that they have a lot of trade studies planned, and they haven’t done the risk comparison with the HLLV approach. The latter surely has to consider that anything that’s only flown once every couple years is intrinsically less reliable, because there’s no way to get the processing team in a rhythm. The SLS is such a monumentally bad idea that it could only have come from Congress.