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The RFI stops - at least explicitly - short of precluding SpaceX bidding with BFS as a lander.
It is certainly capable (in principle) of delivering 500kg to the lunar surface.

Note it's a RFI, it's just asking for ideas, no bidding involved, I don't think they can prevent SpaceX from submitting an answer.

The RFI asks the wrong question.

If NASA is interested in "commercial" options, then NASA should just define the cargo that they want delivered to the Moon, and the frequency of the delivery, and let the marketplace decide how to satisfy that requirement.

Because isn't the goal the cargo, not how it gets there?

I think NASA needs to know the range of lander capabilities first, this is different from ISS resupply since in this case the cargo doesn't exist yet. They should probably design the cargo around the lander capabilities, instead of the other way around, especially considering some potential providers would be modifying existing or planned non-lander hardware to serve as a lander, in which case the payload capabilities would be pre-determined by the base hardware.
While I think BFR/S is awesome, at least a very very large slice of the problem could be solved by fairly minimal technical development missions that get everyone comfortable with the fact that pumps and bolts work in space.
A lot of the above thread is dancing on the heads of pins in order to avoid that.

Yes, things are technically possible with unitary launches, or pretending that specific 'low risk' transfers of fluids or cargo are OK while implicitly assuming others are impossible, but we really need to move on.
Refueling anything that's not autogenously pressurized requires at least three consumable transfer lines with very significant pressure differentials. It's not an easy problem.
SpaceX General Section / Re: Where will BFR be built?
« Last post by RedLineTrain on Today at 03:35 PM »
A relatively modestly-sized factory:  ~200,000 square feet.

32 meter height.  Construction would last 16-18 months.

A smaller 65,000 square foot building (also 32 meter height) would be built earlier.  I guess that's where the early BFS will be built.
I kinda doubt ULA's ELC payments are going to totally disappear, I bet NRO is still going to be paying it (although probably less than the current USAF + NRO amounts).

That would result in yet another lawsuit that would be won (one way or the other) by SpaceX. There is no such thing as a truly competitive environment if the uneven playing field remains in place.
ELC is mandated by law to terminate in 2020 at the latest.

The current form of ELC will terminate, but I think the vision for EELV 2 included some payments for supporting government specific infrastructure and ULA will soon be maintaining two launch pads solely for NRO use.

If ULA is pursuing commercial contracts, they will not be solely for NRO use.

I was talking about the Delta IV pads, which will probably be solely used by NRO for several years.
Space Science Coverage / Re: Pluto-Planet debate discussions
« Last post by as58 on Today at 03:33 PM »
Stern, in the other twit thread,
Typical astronomer. Stick to astronomy,

Stern would've made a great cosmologist.
SpaceX General Section / Re: NASA CRS-7 report released
« Last post by cambrianera on Today at 03:28 PM »
The document refers specifically to 'Impact Strength', is that applicable to the the F9 use case?
The document says:
The impact strength of 17-4 ph, especially large size bar in the H900 and H925 conditions, may be very low at subzero temperatures: consequently the use of 17-4 ph for critical applications at low temperatures should be avoided.
Low impact strength means possibility of brittle fractures, critical application should always avoid brittle behavior.
Yes, it is applicable to F9.

The document also says that for 'Non impact' applications it's OK to use down to -320
Umm, no.
The document says:
For non impact applications, such as valve seats, parts in the H925 condition have performed satisfactorily down to -320°F.
Valve seats are basically scrapers acting on smooth, polished surfaces; they are tested 100% on valves and easily changed during manufacturing. Change on site is more difficult but not uncommon.
And document does not says "it's OK", it says "have performed satisfactorily", like the many SpaceX struts that didn't failed.
What follows is interesting:
The H1100 and H1150 conditions have improved impact strength so that parts made from small-diameter bar can be used down to -100°F with low risk.
Do you really want "low risk" on your multi million dollars rocket?
And do you really think this kind of behavior would allow man rating?

We didn't get one but two failures.  And other undisclosed close calls.

you can't just throw that out there and not do any follow is like teasing the dog..not something one should do. :)
can you give any details??
SpaceX General Section / Re: NASA CRS-7 report released
« Last post by whitelancer64 on Today at 03:19 PM »

In light of the material specification being known to be inappropriate for the application, that quote takes on a very distinct "normalization of deviance" flavor.  That it had not yet failed is not a guarantee it wouldn't fail at some future point.

For a deviance to be normalized, such a deviance needs to happen and then be signed off as acceptable. For example, foam insulation breaking off and striking the orbiter during every shuttle launch. Struts didn't break on every Falcon 9 launch.

And of course, that something didn't break doesn't mean it couldn't break, but that is true of literally every part on everything when it's functioning normally.
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