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The conspiracy theorists of Reddit are having a field day with the "thigh bone" and "spaceship" objects found on Mars' surface...


I refer you to this Wikipedia page:
SFN reports problems with ground systems.
ULA - Delta, Atlas, Vulcan / Re: Reuse business case
« Last post by rst on Today at 09:00 PM »
Has anyone reexamined the original spreadsheet in view of what SpaceX has been observed to be doing?

No, but it was already noted quite a bit earlier that the model is very sensitive to the refurb cost parameter (among others):

Look at row #2:  "Fraction of recovered HW production cost to total launch service cost"
Currently only 60% - so of course reuse makes less sense...  Where is this number from?  Is it applicable to an environment where your rapidly launching a large number of similar missions? (comm sats, refueling, etc)

Now change the number in the spreadsheet from 60% to 70%.  Not a big change, right?

Voila. Suddenly instead of never making sense, RTLS makes sense at 7 flights.

Make it 75%, and RTLS makes sense at 5 flights.

So yeah.  Pick and Choose.

It's been obvious for quite some time that SpaceX has been aiming toward refurb costs way lower than the ULA spreadsheet was assuming.  Per meekGee's original post, the payload penalty assumptions are likewise perhaps high (it's not clear that they were figuring in sea landings).  I don't think I have trustworthy numbers on any of this stuff, but anyone who thinks they do might want to play around a bit...
RP1 freezing point  -36F / -37c

Methane freezing point -295.6F/-182C

It's not a trivial difference.   :( You'd be unwise to try running liquid Methane through the same plumbing as RP1, so you're looking at a whole new set of plumbing, but only for the US.

I'll also note Shotwell said the FH test flight will attempt dual RTLS on the side boosters and barge recovery for the core but on the US she said they will try a "Long coast" for future NSS missions. From the Centaur flights "long coast" is normally < about 8 hours.

No mention of any attempt at US recovery for this flight. Perhaps (as others have speculated) it will be attempted by the test payload.

ITS is much too big for any of the existing pads that SX is using, so any pad would be a clean sheet, so spec'ing Methane rather than RP1 is no big deal. OTOH converting all pads to Methane, or worse still just the US supply, would be a major PITA.

SX's history is to make block changes, not warehouse un used inventory and generally not to look back.
That suggests if they do introduce Raptor into the F9 line they will go the whole hog, scrap Merlin and go Methane throughout. 

Between Merlins further potential thrust upgrades (190Klb?) and  the final introduction of cross feed (if needed) to FH F9 and FH have a very large potential performance stretch, before any engine or propellant changes. Most, if not all, of the Delta IVH payload/velocity profile should be viable with these architectures.

I'm guessing SX know exactly what they'd have to do put FH above the threshold for the SLS Block 1 as well in terms of payload (I think even the minimum PLF diam for SLS is too big a ratio for the F9 dia core), although I strongly doubt they will discuss this openly.   :(
Would it be reasonable to assume that launches would happen from Texas and have their first stages land at Cape Canaveral?

Would launching ITS from Texas be likely? How much more efficient is this than doing RTLS for the first stage?
No commentary while we wait.

Chris, my feed was fine.
Strange. I saw a red, but the webcast died before I could screenshot it?
Not on your end. Happened to me too. Seems to be back now though
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