Author Topic: Commercial Crew (CCtCAP) - Discussion Thread  (Read 261401 times)

Offline deruch

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Re: Commercial Crew (CCtCAP) - Discussion Thread
« Reply #940 on: 11/02/2017 11:33 PM »
NASA can argue the safety standards set are not met and the contractor needs to fix whatever NASA points to at their own cost.
No, NASA won't.
NASA has already been priming ASAP and the HEO - NASA Advisory Committee to except the fact that the originally set LOC/LOM numbers will not be met. That is being done by putting doubt on NASA's own theoretical models for calculating LOC/LOM. Just carefully read the ASAP minutes and HEO - NAC presentations and one can clearly see what is going on: a waiver will eventually be granted for lower LOC/LOM capabilities.

If lower LOC/LOM for capsules are genuinely important then damage when docked to a spacestation can be handled at a system level. Docking bays designed to protect visiting vehicles against debris can be added to the ISS (and DSG). A Kevlar or equivalent wall will do this. Air tight doors are not needed because spacecraft are happy to stay in vacuum providing they are heated.

The LOC/LOM targets are explicitly vehicle side only, without program/operations mitigation.  Which is not to say that there won't be such added, only that the vehicles were supposed to meet the stated target without such.
Shouldn't reality posts be in "Advanced concepts"?  --Nomadd

Offline toren

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An Assessment of Cost Improvements in the NASA COTS/CRS Program and Implications for Future NASA Missions

Edit/gongora:  Links to the entries on NASA Technical Reports Server
Paper
Presentation Slides

This is great stuff!  Real numbers and an understandable presentation.  Kudos to the author.  (I say that as someone with 20-plus years of experience in reading new venture and operational budgets and estimates.)

Offline A_M_Swallow

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Re: Commercial Crew (CCtCAP) - Discussion Thread
« Reply #942 on: 11/02/2017 11:49 PM »
NASA can argue the safety standards set are not met and the contractor needs to fix whatever NASA points to at their own cost.
No, NASA won't.
NASA has already been priming ASAP and the HEO - NASA Advisory Committee to except the fact that the originally set LOC/LOM numbers will not be met. That is being done by putting doubt on NASA's own theoretical models for calculating LOC/LOM. Just carefully read the ASAP minutes and HEO - NAC presentations and one can clearly see what is going on: a waiver will eventually be granted for lower LOC/LOM capabilities.

If lower LOC/LOM for capsules are genuinely important then damage when docked to a spacestation can be handled at a system level. Docking bays designed to protect visiting vehicles against debris can be added to the ISS (and DSG). A Kevlar or equivalent wall will do this. Air tight doors are not needed because spacecraft are happy to stay in vacuum providing they are heated.

The LOC/LOM targets are explicitly vehicle side only, without program/operations mitigation.  Which is not to say that there won't be such added, only that the vehicles were supposed to meet the stated target without such.

Once a waiver exists the problem has to be solved somewhere else.

Offline su27k

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An Assessment of Cost Improvements in the NASA COTS/CRS Program and Implications for Future NASA Missions

Edit/gongora:  Links to the entries on NASA Technical Reports Server
Paper
Presentation Slides

This deserves its own thread, it's too important to be buried under CCtCAP, besides ~50% of the paper is about COTS and CRS, has nothing to do with CCtCAP.

Edit/Lar: Here's the thread: http://forum.nasaspaceflight.com/index.php?topic=44180

Also LOL about the following, I wonder if the author visits NSF:
Quote
It’s worth noting that many an internet discussion about the cost of commercial cargo to the ISS have failed to draw the distinctions that make for rigorous analysis, or even trying to account for major factors. Common errors include using the Space Shuttle programs historical average cost per flightd to calculate costs per kg to the ISS at a low yearly flight rate as a multiple of that average, incorrectly treating the Shuttle’s per flight costs as if NASA could purchase those flights by the yard. To make matters worse, other common errors forget that Shuttle upgrades, though not a recurring yearly operational cost, were a large, ever present and continuous capital expense in every yearly budget. Operating a Shuttle meant continually funding Shuttle upgrades. Other typical errors include using the Shuttle’s maximum payload (not cargo) of about 27,500kg to Low Earth Orbit (LEO) at 200km, then comparing against the commercial prices for ISS cargo (not payload) delivered to the actual, higher 400km ISS orbit. With errors like these such analysis are incorrect (though “not even wrong” might also apply.)
« Last Edit: 11/08/2017 05:30 PM by Lar »

Offline AncientU

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Re: Commercial Crew (CCtCAP) - Discussion Thread
« Reply #944 on: 11/03/2017 11:04 AM »
Agree.  Too broad for this thread...

Examples:
PPP
Quote
Recommendation: We  propose  a  steady  transformation  of  NASA space  exploration  and  operations funding towards more, smaller commercial / public-private partnerships, favoring those with strong non-government business cases,  to increase  the  pace  of NASA achievements and avoid having  most funding in projects with goals forever a generation away.

Depots
Quote
A NASA team looked at propellant depot scenarios in 2011. The cost estimating approach for stages, tankers and the depot have since been refined.  Changes in assumptions are minor (for example, there is no assumption of cost commonality in manufacturing between propulsion stages and depots in the work here, a more conservative assumption).  Overall the new results confirm earlier findings that refueling scenarios are promising, with ample margin for error in cost estimation and for inevitable “unknown unknowns”.  Figure 16 shows an in-space refueling architecture used for lunar exploration where the SpaceX Falcon Heavy in development becomes NASA’s commercial heavy lift provider. The deep space spacecraft and lander are the same as in prior scenarios, also public private  partnerships. The new element is the propellant depot scaled for filling from tankers rendezvousing in low Earth orbit such that enough propellant is available to support 1 lunar mission per year.

Entrenchment
Quote
Reviews of cost over-runs in the US Department of Defense (DoD) note “the well-known bureaucratic power game of front-loading or buying-in.”  Once early funding is spent, this “in effect, gives the contractor permission to use public money to build his political protection network by systematically spreading subcontracts and production facilities to as many congressional districts as possible.”  Inevitably the low operational or per unit costs never materialize as their purpose was only to justify and entrench the early up-front costs.
« Last Edit: 11/03/2017 11:04 AM by AncientU »
"If we shared everything [we are working on] people would think we are insane!"
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Online gongora

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Re: Commercial Crew (CCtCAP) - Discussion Thread
« Reply #945 on: 11/29/2017 05:19 PM »
The slides from the NAC HEO Committee meeting are out.  No official change to dates (will be interesting to see if there are any comments about that during the presentation.)

( the presentations can be found at https://www.nasa.gov/directorates/heo/nac-heoc )
« Last Edit: 11/29/2017 05:20 PM by gongora »

Online gongora

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Re: Commercial Crew (CCtCAP) - Discussion Thread
« Reply #946 on: 11/29/2017 09:10 PM »
The slides from the NAC HEO Committee meeting are out.  No official change to dates (will be interesting to see if there are any comments about that during the presentation.)

( the presentations can be found at https://www.nasa.gov/directorates/heo/nac-heoc )

The dates on the schedule slide are from the beginning of September (the last publicly available update), they get updated about once a quarter.

Offline deruch

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Re: Commercial Crew (CCtCAP) - Discussion Thread
« Reply #947 on: 12/01/2017 07:25 PM »
In the program and safety risks slides, they've left off "Ammonia Emergency Response" this time.  Doesn't necessarily mean that it was closed out, maybe just left off?
Shouldn't reality posts be in "Advanced concepts"?  --Nomadd

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