Commercial Crew Spacecraft Competition

[mr. mark]

http://www.flightglobal.com/news/articles/spacex-completes-system-requirements-review-for-crewed-launches-378446/

SpaceX completes system requirements review for crewed launches 
>

"The SRR, which was completed at a meeting at SpaceX's Hawthorne, California headquarters on 29 October, signify that NASA is satisfied that the Dragon capsule, Falcon 9 launch vehicle and other components of SpaceX's proposal can meet the CCiCap requirements, and that questions raised at the project kickoff meeting in August have been answered or mooted".

[Jim]

Not about ISS reboost. Just what is the maximum altitude can the commercial crew vehicles can get to in their current stack configuration. Someone might want to operate some sort of facility/platform higher up than the ISS requiring visits in the future.

Boeing and SNC can add more solids to the Atlas to increase altitude as desired

[pathfinder_01]

Not about ISS reboost. Just what is the maximum altitude can the commercial crew vehicles can get to in their current stack configuration. Someone might want to operate some sort of facility/platform higher up than the ISS requiring visits in the future.

The issuse might be less rocket performance and more TPS and other system issuses. I know the shuttle was limited in how high it could go and safely return by it's TPS system.

[Go4TLI]

Not about ISS reboost. Just what is the maximum altitude can the commercial crew vehicles can get to in their current stack configuration. Someone might want to operate some sort of facility/platform higher up than the ISS requiring visits in the future.

The issuse might be less rocket performance and more TPS and other system issuses. I know the shuttle was limited in how high it could go and safely return by it's TPS system.

No.  The orbiter was limited based on prop quantity since it took a substantial amount to get the vehicle and payload to altitude and then still having enough to de-orbit the large vehicle in a standard amount of time

[Oberon_Command]

Not about ISS reboost. Just what is the maximum altitude can the commercial crew vehicles can get to in their current stack configuration. Someone might want to operate some sort of facility/platform higher up than the ISS requiring visits in the future.

The issuse might be less rocket performance and more TPS and other system issuses. I know the shuttle was limited in how high it could go and safely return by it's TPS system.

No.  The orbiter was limited based on prop quantity since it took a substantial amount to get the vehicle and payload to altitude and then still having enough to de-orbit the large vehicle in a standard amount of time

Was there an known entry velocity that the orbiters were rated to? How high could an orbiter go assuming it had the propellant?

[joek]

Not about ISS reboost. Just what is the maximum altitude can the commercial crew vehicles can get to in their current stack configuration. Someone might want to operate some sort of facility/platform higher up than the ISS requiring visits in the future.

Good question, especially since we don't really have anything definitive as to a "current stack configuration".  IIRC commercial CTS requires nominal ~400km(?) reach.  Presumably anything above that would be a lower payload?  Unless the CTS contenders have more margin than required?

[Garrett]

Not about ISS reboost. Just what is the maximum altitude can the commercial crew vehicles can get to in their current stack configuration. Someone might want to operate some sort of facility/platform higher up than the ISS requiring visits in the future.

The issuse might be less rocket performance and more TPS and other system issuses. I know the shuttle was limited in how high it could go and safely return by it's TPS system.

No.  The orbiter was limited based on prop quantity since it took a substantial amount to get the vehicle and payload to altitude and then still having enough to de-orbit the large vehicle in a standard amount of time

Was there an known entry velocity that the orbiters were rated to? How high could an orbiter go assuming it had the propellant?

FWIW, orbital velocities decrease with increasing altitude.
I don't know how that works for reentry velocities however. My first intuition would be that reentry velocities also decrease, but then I also presume that the craft picks up extra vertical velocity from "falling" to Earth during reentry?

[Jason1701]

Not about ISS reboost. Just what is the maximum altitude can the commercial crew vehicles can get to in their current stack configuration. Someone might want to operate some sort of facility/platform higher up than the ISS requiring visits in the future.

The issuse might be less rocket performance and more TPS and other system issuses. I know the shuttle was limited in how high it could go and safely return by it's TPS system.

No.  The orbiter was limited based on prop quantity since it took a substantial amount to get the vehicle and payload to altitude and then still having enough to de-orbit the large vehicle in a standard amount of time

Was there an known entry velocity that the orbiters were rated to? How high could an orbiter go assuming it had the propellant?

FWIW, orbital velocities decrease with increasing altitude.
I don't know how that works for reentry velocities however. My first intuition would be that reentry velocities also decrease, but then I also presume that the craft picks up extra vertical velocity from "falling" to Earth during reentry?

All vehicles have the same gravitational potential when they hit the atmosphere, so their speed at entry interface goes up with the square root of their previous orbital radius.

[JohnFornaro]

Everyone misses the point and the process should be kept in perspective, it’s a "Competition".   The best that met the specs should get into the next round period.

Those firms who have bragged about continuing "no matter what" will have to put up, or shut up.   All the firms have a chance to be in final "Competition" for the contract in aprox two years.  That being said only stupid firms would bring this into a court.

Anything that needs correcting?

Only the word "stupid".  Any firms bringing that hypothetical case would pat themselves on the back as being "smart".  Those of us who like the idea of "competition", would call them "obstructionists", on the other hand.  "Wasters of time and effort", maybe, but not really "stupid".

The scaled comparison fotos up there are particularly good.  Note how four of the five designs start looking very much alike.  This demonstrates one of my sketchy principles:  A pound of spacecraft is a pound of spacecraft, when functionality and operation remains constant.  When you add wings the pound per spacecraft ratio changes, which is not surprising since there is a fundamental change of functionality and operation.

Great thread, very informative.

[Lobo]

Not about ISS reboost. Just what is the maximum altitude can the commercial crew vehicles can get to in their current stack configuration. Someone might want to operate some sort of facility/platform higher up than the ISS requiring visits in the future.

Boeing and SNC can add more solids to the Atlas to increase altitude as desired

Will the Atlas SRB's be man rated too?  I thought the plan was to use an SRB-less Atlas so they wouldn't have to deal with man-rating them?

[Lars_J]

Not about ISS reboost. Just what is the maximum altitude can the commercial crew vehicles can get to in their current stack configuration. Someone might want to operate some sort of facility/platform higher up than the ISS requiring visits in the future.

Boeing and SNC can add more solids to the Atlas to increase altitude as desired

Will the Atlas SRB's be man rated too?  I thought the plan was to use an SRB-less Atlas so they wouldn't have to deal with man-rating them?

AFAIK, CST-100 is already going to be launched with the 412 variant of Atlas V - 1 solid.

[Lobo]

Not about ISS reboost. Just what is the maximum altitude can the commercial crew vehicles can get to in their current stack configuration. Someone might want to operate some sort of facility/platform higher up than the ISS requiring visits in the future.

Boeing and SNC can add more solids to the Atlas to increase altitude as desired

Will the Atlas SRB's be man rated too?  I thought the plan was to use an SRB-less Atlas so they wouldn't have to deal with man-rating them?

AFAIK, CST-100 is already going to be launched with the 412 variant of Atlas V - 1 solid.

Ok, thanks, so apparently that's a "yes".  I thought both SNC and Boeing were using AV402's. 
Any idea of what's involved in modifying the standard Atlas SRB to make it man-rated?  if anything?

[hkultala]

Not about ISS reboost. Just what is the maximum altitude can the commercial crew vehicles can get to in their current stack configuration. Someone might want to operate some sort of facility/platform higher up than the ISS requiring visits in the future.

Boeing and SNC can add more solids to the Atlas to increase altitude as desired

Will the Atlas SRB's be man rated too?  I thought the plan was to use an SRB-less Atlas so they wouldn't have to deal with man-rating them?

AFAIK, CST-100 is already going to be launched with the 412 variant of Atlas V - 1 solid.

I think you remember incorrectly. It's 402, not 412.

Osc Prometheus was planning to use 412, but it has been canned a long time ago.

So no man-rated solids for atlas.

[Lars_J]

AFAIK, CST-100 is already going to be launched with the 412 variant of Atlas V - 1 solid.

I think you remember incorrectly. It's 402, not 412.

Osc Prometheus was planning to use 412, but it has been canned a long time ago.

So no man-rated solids for atlas.

My source, an article on this site: http://www.nasaspaceflight.com/2011/08/atlas-v-wins-boeing-selects-launcher-cst-100-capsule/

...According to Dr Sowers, the Atlas V will fly in the 412 configuration, involving one solid strap-on booster and a dual-engine Centaur Upper Stage...

Another source: http://spaceflightnow.com/news/n1108/04boeingatlas/

That might have changed since then, but at the time of the announcement, the 412 configuration was the chosen one.

[yg1968]

You are right, the CST-100 will use the Atlas V 412. It has not changed and it has been mentionned a number of times. In Boeing's CCiCap SAA, there is a picture of an Atlas V 412.

[Lobo]

There’s some interesting news on the DC, as it seems to be proceeding well. 

It’s a fan favorite for sure.  I’m just wondering how things will shake out in the long run.  Sounds like they want Commercial crew to be downselected to just one.  Not sure what they’ll do for commercial cargo once the SpaceX and OSC contracts are filled.  Will they keep both or down select to one?

Seems like ultimately, probably the best fiscal sense would be to get down to two suppliers who can both do cargo and crew.  Cygnus can’t do crew obviously, and DC can’t do unpressurized cargo, and not a lot of pressurized cargo.  So maybe DC gets cut before the final downselect for crew and Cygnus is cancelled once it’s current cargo contract is done?  Leaving CST-100 and Dragon.  Both could do crew and cargo.  Dragon already has a trunk, so they could do unpressurized cargo during a crew mission.  And, since commercial crew vehicles can handle 7 people, but likely won’t be taking up any more than 3 or 4 at a time (Russians will continue doing their own crew rotations I’m pretty sure), that means Dragon wouldn’t need both rows of seats.  They could have Dragon set up for four crew, and use the area behind for a fair amount of pressurized cargo, as well as unpressurized cargo in the trunk.
(I’m assuming the robot arm could unload the trunk if Dragon is at the docking port instead of the berthing port?)

I would assume CST-100 will be similar.  That would mean that crew and pressurized cargo can be combined.  Perhaps augmented by dedicated cargo for large pressurized components and/or if unpressurized cargo cannot be accessed while a capsule is at the docking port.  See below, and imagine the back row of 3 seats taken out, and that volume filled with storage racks for pressurized cargo like the current cargo dragon is.

This seems like the most efficient way to go.  However, DC seems to have a lot of support by fans, and it would seem by some in NASA.  NASA seems pretty interested in it, and are apparently planning on leasing them a OPF for processing them?  Probably not something they’d be worrying about right now if they didn’t think DC had a pretty good shot.  They are doing the same for CST-100 too.  So I just can’t see how this all shakes out in the end.  Anyone have some educated guesses on that?

[Zed_Noir]

Seems like ultimately, probably the best fiscal sense would be to get down to two suppliers who can both do cargo and crew.  Cygnus can’t do crew obviously, and DC can’t do unpressurized cargo, and not a lot of pressurized cargo.  So maybe DC gets cut before the final downselect for crew and Cygnus is cancelled once it’s current cargo contract is done?  Leaving CST-100 and Dragon.  Both could do crew and cargo. 

There is the possibility that Orbital could send the Cygnus up on the Falcon 9. After all, what matters is tonnage delivered, not the delivery vehicle. So SpaceX becomes one service provider with 2 delivery vehicles (Dragon & Cygnus).

The CST-100 might not come online if Boeing doesn't put up some money itself.

[yg1968]

I am not sure why SpaceX would compete against itself. I also doubt that Orbital would want to use the Falcon 9 for its spacecraft given that it already has Antares.

[thydusk666]

There is the possibility that Orbital could send the Cygnus up on the Falcon 9.

Where did you get that from?

[Comga]

(I’m assuming the robot arm could unload the trunk if Dragon is at the docking port instead of the berthing port?)

Simple questions get lost in long posts, but this one is interesting and should have a simple answer. 
Could the SSRMS reach into the trunk of a crew version of Dragon if that capsule was docked to the forward port on Node 2?