ISS Commercial Resupply Services 2 (CRS2) 2017-2030

[QuantumG]

Who might have asked those two questions...?

SNC.

[baldusi]

Who might have asked those two questions...?

SNC.

Funny, I thought it was a rhetorical question.

[Llian Rhydderch]

Here is an article on CRS2:
ISS Cargo Shippers Face Competition from Space Taxis

Lovely.  What a novel idea!   

 ==>  Market competition from companies who are independently designing their own alternatives for meeting a set of requirements published by the government, and paid only for services rather than government ownership of the vehicles and technology. 

May a thousand flowers bloom! 

[John Santos]

Not sure if this is the right place for this, but would it be possible - with millimetre-tolerance close-quarters manouevring - to have the visiting vehicle dock without arm assistance at what are currently regarded as berthing ports? Would there be any significant practical advantage to that? Would NASA see it as a desirable capability?

No, absolutely not - CBMs are not designed to take the impacts that docking would impart. There is no capture ring to take the loads, and so the seals of the CBMs themselves would be damaged.

You would have to have some way to slowly and precisely position the VV against the CBM, then activate the capture bolts (which are on the active, i.e. ISS side).  To do this it might be helpful to have a mechanism to grab onto the ISS near the CBM at some convenient hard point, and a method to then precisely move the VV's CBM into position against the ISS's CBM.  Oh, I got it!     Put an arm with a grappling fixture on the visiting vehicle (controlled from the VV), grapple one of the FRGF or PDGF's near the CBM, and berth.  This would solve one of the issues with "Why must a visiting crewed vehicle dock with the ISS instead of berth with it?"  This is how the shuttle berthed new modules (though not itself) with the station before the station got its own Canadarm and a crew to operate it.

There still remain at least two technical problems that I know of, 1) the hatches on the ISS side of the CBMs can only be opened or closed from the inside (I'm pretty sure this was one of Jim's points), and the deberthing process is too slow for an emergency evacuation.  Plus a serious cost problem: unless you have some way to stow the arm inside the VV (like the shuttle did), you need a new one for each flight, and I'm sure they are very expensive.

I don't understand why people seem so dead set on being able to berth crewed visiting vehicles.  It would take several years at least to add an arm to Dragon, Dreamchaser or CST-100 (if you could find room for it), train the crews to use it, and so forth, when it would probably take less time to use the already planned docking mechanism.  I don't think this would speed up commercial crew, just slow it down.

EDIT: Or maybe I misunderstood.  Are you just proposing this as a method of attaching uncrewed VVs that wouldn't require so much crew time?  If so, my two technical objections wouldn't apply.  But if it were possible to remotely operate the VV's arm to do a berthing, it should be equally possible to remotely operate the station's arm.

[AnalogMan]

NASA has just posted the Draft Request for Proposal (RFP) for CRS2.
https://www.fbo.gov/spg/NASA/JSC/OPDC20220/NNJ14507542R/listing.html

Pre-solicitation Conference to be held August 7, 2014.  Comments and inquiries on dRFP due on or before July 18, 2014 for inclusion in conference.

Couple of quick notes:

Pricing to be based on missions instead of kilograms delivered or returned.

NASA Docking System (NDS) build-to-print data will be available for CRS2.  Final determination has not been made on if the NDS will be available as Government Furnished Property.

https://prod.nais.nasa.gov/eps/eps_data/160726-DRAFT-001-003.docx (265 pages)
https://prod.nais.nasa.gov/eps/eps_data/160726-DRAFT-001-001.pdf (covering letter)

Copy of Draft RFP in pdf format also attached.

[yg1968]

Pages 3 and 4 of the document (pages 7 and 8 of the PDF) provides a good overview of the requirements.

[yg1968]

Contract award date for CRS2 has been added:

Release Final Request for Proposal 09/30/14   
Proposals Due 11/14/14   
Contract Award 04/28/15

http://procurement.jsc.nasa.gov/crs2/schedule.asp

[yg1968]

August 7 pre-proposal conference presentation:
http://prod.nais.nasa.gov/eps/eps_data/160726-OTHER-001-001.ppt

[yg1968]

Q&A on the draft RFP (post #1):
https://prod.nais.nasa.gov/eps/eps_data/160726-OTHER-002-001.pdf

[yg1968]

August 7 pre-proposal conference presentation:
http://prod.nais.nasa.gov/eps/eps_data/160726-OTHER-001-001.ppt

Price is the most important selection criteria (see slide 41):

Relative Order of Importance

Price is approximately equal to the combination of Mission Suitability and Past Performance. 
Mission Suitability is more important than Past Performance. 
Price is more important than Mission Suitability. 
Price is more important than Past Performance. 

[Coastal Ron]

Here is an article on CRS2:
ISS Cargo Shippers Face Competition from Space Taxis

Lovely.  What a novel idea!   

 ==>  Market competition from companies who are independently designing their own alternatives for meeting a set of requirements published by the government, and paid only for services rather than government ownership of the vehicles and technology. 

May a thousand flowers bloom! 

In that article it has a quote from Boeing about the CST-100:

"With no crew, the capsule will be able to carry more than 1,100 kilograms of cargo"

Not sure I've seen that figure before, and it's interesting.  Dragon can carry about 3,310 kg of pressurized cargo to the ISS and return the same, and the Cygnus can carry 1,800 kg to the ISS.

So if price is the primary consideration the CST-100 will be challenged, since it would require 18 flights to deliver 20mt of supplies to the ISS vs 12 flights for Cygnus.  However CST-100 can return mass safely to Earth so that might be a consideration.

More food for thought until the CCtCap contract winners are announced, which should provide some insight into who the CRS2 competitors will be.

[QuantumG]

"With no crew, the capsule will be able to carry more than 1,100 kilograms of cargo"

Not sure I've seen that figure before, and it's interesting.  Dragon can carry about 3,310 kg of pressurized cargo to the ISS and return the same, and the Cygnus can carry 1,800 kg to the ISS.

Maybe Boeing and Cygnus are using a sensible means of calculating up mass. SpaceX hasn't flown a single Dragon flight with up mass even close to their claims.

[Borklund]

"With no crew, the capsule will be able to carry more than 1,100 kilograms of cargo"

Not sure I've seen that figure before, and it's interesting.  Dragon can carry about 3,310 kg of pressurized cargo to the ISS and return the same, and the Cygnus can carry 1,800 kg to the ISS.

Maybe Boeing and Cygnus are using a sensible means of calculating up mass. SpaceX hasn't flown a single Dragon flight with up mass even close to their claims.

Because NASA hasn't manifested that much cargo on any single flight. Doesn't mean it's not true. SpaceX can't just put random stuff in there to demonstrate capability, in order to satisfy obsessive forum dwellers.

[guckyfan]

"With no crew, the capsule will be able to carry more than 1,100 kilograms of cargo"

Not sure I've seen that figure before, and it's interesting.  Dragon can carry about 3,310 kg of pressurized cargo to the ISS and return the same, and the Cygnus can carry 1,800 kg to the ISS.

Maybe Boeing and Cygnus are using a sensible means of calculating up mass. SpaceX hasn't flown a single Dragon flight with up mass even close to their claims.

This is insulting SpaceX. They have stated a capability and there is no reason whatsoever to doubt it. It is just that there is another capability, the well known volume and shape of the Dragon capsule.

[docmordrid]

"With no crew, the capsule will be able to carry more than 1,100 kilograms of cargo"

Not sure I've seen that figure before, and it's interesting.  Dragon can carry about 3,310 kg of pressurized cargo to the ISS and return the same, and the Cygnus can carry 1,800 kg to the ISS.

Maybe Boeing and Cygnus are using a sensible means of calculating up mass. SpaceX hasn't flown a single Dragon flight with up mass even close to their claims.

Do you always fill the back of your vehicle to the max? Neither does NASA. ISTM they ship what's needed and ready. Ship more and the ISS crew may not have room to stow it and the trash  they've generated.

[QuantumG]

All I'm saying is that maybe Boeing and Orbital Sciences are estimating their payload capability in a way that is actually relevant to how NASA is going to use it. SpaceX didn't. There's no reason to get all defensive about it.

[baldusi]

Cargo CST-100 could launch on an 431, which might mean that they have more than enough margin to fill those 12m3.

[Nomadd]

 It seems off that deleting 7 crew with all the associated hardware would only give you 1100 kg cargo capability. I wonder if that number might be for a lifeboat capable capsule with everything needed for a six month stay and a trip home with crew.

[Garrett]

"With no crew, the capsule will be able to carry more than 1,100 kilograms of cargo"

Not sure I've seen that figure before, and it's interesting.  Dragon can carry about 3,310 kg of pressurized cargo to the ISS and return the same, and the Cygnus can carry 1,800 kg to the ISS.

Maybe Boeing and Cygnus are using a sensible means of calculating up mass. SpaceX hasn't flown a single Dragon flight with up mass even close to their claims.

Do you always fill the back of your vehicle to the max? Neither does NASA. ISTM they ship what's needed and ready. Ship more and the ISS crew may not have room to stow it and the trash  they've generated.

I don't think it's a question of not being able to stow stuff. The ATV and HTV bring up heavier loads as far as I can recall.

The Spx-4 mission is set to bring about 2300 kg (see this post), which is quite substantial.

Given the type of cargo being transported, I believe Dragon will always be volume limited so that we'll never see 3300 kg of payload during the current CRS contract. I think there's a quote out there to support that.

Also, it's likely that SpaceX designed Dragon with more mass carrying ability than was necessary for CRS as their Chief Designer is believed to have big ambitions ...

[abaddon]

All I'm saying is that maybe Boeing and Orbital Sciences are estimating their payload capability in a way that is actually relevant to how NASA is going to use it. SpaceX didn't. There's no reason to get all defensive about it.

According to the Cygnus fact sheet http://www.orbital.com/AdvancedSystems/Publications/Cygnus_factsheet.pdf Cygnus can take 2000kg (current version) or 2700kg (enhanced version, to debut Orb CRS 4.  The enhanced Cygnus requires the Antares 130 which is supposed to debut in the next mission).  Missions so far have delivered less mass than the 2000kg max of the current version; 700kg, 1261kg, 1494kg for an average of 1152kg per flight.  Excluding the demo mission it's still only 1377kg per flight, which extended out over the full flight manifest would result in just over 54% of the total upmass they are supposedly contracted to take to the station.  Even if all future flights take full upmass (2000kg for the next flight, 2700kg for the last five flights) and including the demo flight they still fall short of 20,000kg by over 1000 kg.  And we've seen nothing to date to suggest that any, let alone all future flights, will maximize the capacity of Cygnus.

Doesn't seem all that different from SpaceX to me.

[EDIT] I take that back, after running the numbers for Dragon this seems worse.
[EDIT2] Some small fixes to numbers, no real effect though.