For those of you who can afford it, but who haven’t done so yet, I’d suggest getting a subscription to the L2 section of Chris Bergin’sNASASpaceflight.com forum. They’ve typically been well ahead of the ball on several of the major NASA CxP stories that have broken over the last few years. And a lot of their work involves more than just calling up the NASA Public Affairs Office and then repeating their talking points verbatim and calling it investigative journalism.
One of the latest gems, which by itself would make an L2 subscription worthwhile (if you’re interested in the Constellation Program), is the release of 11 of the 12 ESAS Appendices (the one containing financial data on various launchers has some proprietary data in it, so it wasn’t able to be posted). These are where a lot of the methodology, data, and ground assumptions for the ESAS study were documented. Doug Stanley had referenced them during some of his Q&A threads there on the NSF forums, and originally they were supposed to be publicly released, but NASA decided not to release any of them, even though only one part had sensitive information.
Now, having seen some of what’s in them (I’ve mostly been focusing on the 300+ page appendix to Chapter 6, that details all of their launch vehicle related decisions), I can understand why some people might not want that data to see the light of day. I was hoping to get permission to post a screenshot or two and some direct quotes, but for now you’ll have to get a subscription and check it out yourself.
Some gems to look for when you get a chance, all within the first 40 pages:
- Exceptions given in the ground rules and assumptions on maximum dynamic pressures to In-line SRM based crew launch concepts that weren’t given to any other vehicles (without the exception, all of the five-segment Stick concepts would’ve been ruled out from the start).
- Unrealistically assuming a fixed LAS mass regardless of first stage characteristics (like T/W, max-Q, and whether you can shut them down or not).
- Inaccurate dry mass numbers for existing EELV upper stages (just as some of the guys on NASASpaceflight.com had been saying for years now).
And more. I hope someone can get NASA to finally release these publicly, because these discrepencies need to be explained. Hopefully if NASA ever does a study like this again in the future, they’ll be more open along the way, and thus expose themselves to less negative feedback when their data finally does see the light of day.
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