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Dragon to cost about $140 million per launch



 
 
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  #21  
Old October 27th 11, 01:11 PM posted to sci.space.shuttle
Bob Haller
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Posts: 3,197
Default Dragon to cost about $140 million per launch


No, I didn't. *My original comment was that Dragon was quoted by SpaceX
as being about one-tenth the cost of a Shuttle mission. *$1.4 billion
divided by 140 equals 0.1.

For a crew changeover mission, it's still going to be much less
expensive to use Dragon than to use Shuttle; even with a resupply
performed by shuttle at the same time. *They've never transferred more
than few tonnes at each shuttle docking, except modules (hardly relevant)..-


since the standing army cost to launch any shuttle was a ongoing
expense......

5 billion per year with one shuttle launched every 2 years, the cost
of a single flight every other year
10 BILLION

unless shuttle C had been built..... the infrastructure and launch
teams the same, it would of retained the unique shuttle abilities at a
realtively low cost.....

featuring multiple resupply trips, the ability to launch new modules
and big replacement parts, add a capsule somehow to the C version,
with better safety, like launch boost escape...

when a shuttle did fly, minimially man it with crew of 2, with
ejection seats. or a jetisonable crew pod.....

  #22  
Old October 27th 11, 01:49 PM posted to sci.space.shuttle
Jeff Findley[_2_]
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Posts: 1,388
Default Dragon to cost about $140 million per launch

In article , bthorn64
@suddenlink.net says...

On Thu, 27 Oct 2011 10:31:24 +1100, Alan Erskine
wrote:
There's another point to this. If anyone wants to build a

replacement
for ISS, they will be able to use Falcon Heavy - more than twice the
payload of Shuttle.


What would perform the control, communications, rendezvous and
docking? Could a Dragon fly around with 35,000 lbs. of module on its
nose?


Possibly. If it doesn't have the fuel capacity needed, you could stack
two Dragon service modules top of each other. Falcon Heavy gives you
plenty of options to "throw mass" at this problem.

Another possibility is the satellite bus that Orbital Sciences is using
for their COTS station resupply spacecraft.

Jeff
--
" Ares 1 is a prime example of the fact that NASA just can't get it
up anymore... and when they can, it doesn't stay up long. "
- tinker
  #23  
Old October 27th 11, 02:03 PM posted to sci.space.shuttle
Jeff Findley[_2_]
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Posts: 1,388
Default Dragon to cost about $140 million per launch

In article , bthorn64
@suddenlink.net says...

On Wed, 26 Oct 2011 08:14:03 -0400, Jeff Findley
wrote:

MPLM cargo is a bit more than 9,000 kg. Dragon up-mass is 6,000 kg and
down-mass is 3,000 kg. In crew mode, Dragon supports up to 7
passengers.


I don't believe Dragon is going to get anywhere near 6,000kg mass to
ISS. Its shape and volume just don't lend themselves to it. I'll be
happy to be proven wrong, though.


That's the capacity SpaceX is advertising. Agreed that in practice,
this could be different.

Again, ISS assembly is complete. There is no requirement to

duplicate
shuttle's ability to deliver entire station modules to ISS. The
requirement is cargo deliveries (and later crew rotation flights) .


I'm not the one who compared Dragon's cost to Shuttle's cost. Alan
opened that door, so the defense of Shuttle is allowed.

In any case, I think we're living dangerously in having no 'large
upmass' capability for Station. Are you really so certain there won't
be another SARJ failure or something else requiring a big spare part
that NASA has no way to launch anymore?

And there is still talk of Node 4 to fly as an "exploration node" to
ISS.


I'd think that Delta IV Heavy or Falcon Heavy could loft large masses to
ISS when used in conjunction with a Dragon service module or the service
module that Orbital Sciences is using on their ISS resupply craft. The
Russians have done the same thing with a Progress service module to
deliver their docking modules to ISS (launched on a Soyuz launch
vehicle). That and they've used TKS derived service modules to deliver
large station modules (launched on Proton). Certainly the US can do the
same.

Dragon Payload Volume: 10 m3 (350 ft3) pressurized and 14 m3 (490 ft3)
unpressurized compared to MPLM's pressurized volume of 31 m3. MPLM has
about a 3 to 1 advantage in volume.


I think it will be closer to 4 to 1 when you factor in volume that has
to be set aside for the hatch, etc., in a basically conical structure.
I said before, Dragon will run out of room (volume) long before it
runs out of mass. I stand by that, but will be happy to admit I was
wrong if SpaceX pulls it off.

The other part of the 6 to 1 is the mass carried in addition to the
MPLM by the Shuttle. Such as CMGs or ammonia tanks on the MPESS, and
all the water delivered from Shuttle's fuel cells, which was
substantial, not counted as Shuttle cargo, and counted as pure cargo
by all other cargo haulers.


So you weren't looking at a specific STS mission carrying an MPLM when
you came up with your 6:1 ratio?

Obviously the shuttle's unpressurized volume is huge, but again, we're
talking ISS resupply missions, not assembly missions, so volume isn't
quite as critical.


Whoever said resupply only involves internal stowage? Kibo and
Columbus were both built with external science equipment in mind, and
now there is very little opportunity to fly external experiments. What
little external capacity HTV has will likely end up being used for
critical replacement parts like CMGs or ammonia tanks.


Very little opportunity? I think not. HTV is flying and has provisions
for unpressurized cargo. Dragon does as well (14 m3 volume for
unpressurized cargo). I'm not sure about OSC's vehicle...

Total program cost for the shuttle was $196 billion in 2011 dollars.
There were 135 missions (including the two which destroyed Challenger
and Columbia) so the cost per flight was $1.45 billion dollars.


While that's true, Shuttle in an operational sense didn't cost that
much. We already had Shuttle, we didn't have Falcon 9/Dragon. It
wasn't going to cost $1.45 billion per flight out of NASA's budget at
the time NASA was deciding whether or not to extend Shuttle. It was
$700 million or so out of the U.S. Treasury per flight each year in
2006-2010. (It was a little higher than that, but I think we must
assume that other "space support" budget would continue to exist if
Shuttle were replaced by Dragon.)

$700 million for one Shuttle flight versus, call it one Manned Dragon
flight at $140 million each and four or five Cargo Dragons at, what
$100 million each? The numbers get interesting.


While the numbers are "interesting", shuttle isn't flying anymore.
Commercial competition for ISS resupply is the capitalist way to go
about moving forward. Costs should drop as competition should spur the
commercial providers to innovate in a way that the prior single source
cost-plus contracts did not.

You're not a socialist, are you? ;-)

If Dragon really does take six flights to replicate a typical shuttle
crew rotation and resupply mission (I doubt it would), each Dragon
flight would need to cost more than $240 million dollars.


I think $150-200 million is probably going to be the ballpark for
Manned Dragon, and I think that's a bargain. They currently claim $140
million, if I heard right, but Falcon 1 and 9 have both busted their
budgets in the past (they are still very cheap, I'm not claiming
otherwise, just not as cheap as they originally hinted they would be).
If SpaceX ends up on the high side at $200 million, is losing
Shuttle's huge upmass, downmass, and impressive in situ
construction/repair capability, and the option to fly other missions
like another Hubble repair (looking all the more desirable now that
Webb has completely screwed the pooch) really worth $40 million?


It will be interesting. SpaceX is working hard on making Falcon 9's
first stage reusable. Even if they fail at this, reusable boosters for
Falcon Heavy (a much easier problem to solve) would make 1/2 of the
stages reusable, which means well over half of the engines could be
reused per launch. Reusability could be a huge game changer for SpaceX
both in terms of improved reliability and reduced cost.

If the number
is four Dragon flights to equal a typical MPLM flight, then SpaceX only
needs to cost less than $360 million dollars.


I think they'd have to screw up a lot, or be NASA regulationed to
death to hit that high. Unfortunately, both are completely within the
realm of possibility.


True, but to me, this is still better than SLS. The one silver lining
to NASA screwing the pooch on Ares I and Orion is that they *have* to
rely on commercial providers for ISS resupply. If Ares I and Orion were
flying, NASA might have given a single finger salute to the commercial
providers and continued along the socialist path of US government only
vehicles flying to ISS.

I'm betting SpaceX can come in with costs lower than that if it's
successful in reusing Dragon multiple times, which is the plan.


I'm betting they might be able to lower costs, but they won't actually
cut their prices. Mr. Musk is still a capitalist at heart. He'll lower
his prices only so far to win contracts, no farther.

Kind of a moot point since shuttle is retired. Comparing Dragon to
Progress and Soyuz (or ATV or HTV) is a better choice.


Just reponding originally to Alan, who compared one apple (Dragon) to
a bushel of apples (Shuttle.)


Ok.

Jeff
--
" Ares 1 is a prime example of the fact that NASA just can't get it
up anymore... and when they can, it doesn't stay up long. "
- tinker
  #24  
Old October 27th 11, 07:49 PM posted to sci.space.shuttle
Jorge R. Frank
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Posts: 2,089
Default Dragon to cost about $140 million per launch

On 10/27/2011 08:03 AM, Jeff Findley wrote:

I'd think that Delta IV Heavy or Falcon Heavy could loft large masses to
ISS when used in conjunction with a Dragon service module


Dragon doesn't have a service module, as that term is usually
understood. The "trunk", as SpaceX calls it, contains only the solar
arrays, radiators, and external cargo accommodation. *All* Dragon
propulsion capability is integrated into the capsule itself.

or the service
module that Orbital Sciences is using on their ISS resupply craft. The
Russians have done the same thing with a Progress service module to
deliver their docking modules to ISS (launched on a Soyuz launch
vehicle). That and they've used TKS derived service modules to deliver
large station modules (launched on Proton). Certainly the US can do the
same.


You can't just slap an inert module on the end of a service module and
expect the stack to be controllable. If you look carefully at Orbital's
Cygnus, the pressurized module has RCS clusters arrayed around the front
end. They're fed by propellant lines running *through the module* to the
service module in the aft end.

Ditto the Progress-derived modules and the TKS. They've got RCS clusters
at both ends for controllability.

Bottom line is that the ISS module must be fairly tightly integrated
with the service module.

Very little opportunity? I think not. HTV is flying and has provisions
for unpressurized cargo. Dragon does as well (14 m3 volume for
unpressurized cargo). I'm not sure about OSC's vehicle...


Current version of Cygnus has no unpressurized cargo accommodation, but
a variant could be developed that would do so.

If the number
is four Dragon flights to equal a typical MPLM flight, then SpaceX only
needs to cost less than $360 million dollars.


I think they'd have to screw up a lot, or be NASA regulationed to
death to hit that high. Unfortunately, both are completely within the
realm of possibility.


True, but to me, this is still better than SLS. The one silver lining
to NASA screwing the pooch on Ares I and Orion is that they *have* to
rely on commercial providers for ISS resupply.


Well, no, they *could* just continue to use Soyuz and Progress provided
Congress continues to waive INKSNA. Might even be cheaper if ISS ends in
2020.

  #25  
Old October 27th 11, 07:52 PM posted to sci.space.shuttle
Jorge R. Frank
external usenet poster
 
Posts: 2,089
Default Dragon to cost about $140 million per launch

On 10/27/2011 07:49 AM, Jeff Findley wrote:
In , bthorn64
@suddenlink.net says...

On Thu, 27 Oct 2011 10:31:24 +1100, Alan Erskine
wrote:
There's another point to this. If anyone wants to build a

replacement
for ISS, they will be able to use Falcon Heavy - more than twice the
payload of Shuttle.


What would perform the control, communications, rendezvous and
docking? Could a Dragon fly around with 35,000 lbs. of module on its
nose?


Possibly. If it doesn't have the fuel capacity needed, you could stack
two Dragon service modules top of each other. Falcon Heavy gives you
plenty of options to "throw mass" at this problem.


I already addressed part of this in my other reply, but if you're going
to use two Dragons for this task, you need two Dragon *capsules* (Dragon
doesn't have a service module) and the capsules would need to be on
opposite ends of the module to provide sufficient control authority.

Another possibility is the satellite bus that Orbital Sciences is using
for their COTS station resupply spacecraft.


Ditto here, unless you plan to mount RCS clusters to the other end of
the module, as Orbital is doing with Cygnus.

  #26  
Old October 27th 11, 09:01 PM posted to sci.space.shuttle
snidely
external usenet poster
 
Posts: 1,303
Default Dragon to cost about $140 million per launch

"Jorge R. Frank" scribbled something like ...

You can't just slap an inert module on the end of a service module and
expect the stack to be controllable. If you look carefully at
Orbital's Cygnus, the pressurized module has RCS clusters arrayed
around the front end. They're fed by propellant lines running *through
the module* to the service module in the aft end.

Ditto the Progress-derived modules and the TKS. They've got RCS
clusters at both ends for controllability.

Bottom line is that the ISS module must be fairly tightly integrated
with the service module.


Seems to me the control-of-jets issue is more important than shared
plumbing. I'd be thinking about 2 "thin" service modules, with either a
wireless connection to a common control port, or a connection that could
use a data bus that would be part of the payload module anyway.

/dps
  #27  
Old October 27th 11, 09:38 PM posted to sci.space.shuttle
snidely
external usenet poster
 
Posts: 1,303
Default ISS re-entry scenarios (was Dragon to cost about ...)

"Jorge R. Frank" scribbled something like ...
[...] if ISS ends in 2020.


Wandering a bit further afield, have you heard if the simulations show any
difference in how much debris will reach the earth for a whole-ISS entry
interface vs individual modules entering seperately?

I understand that "picking one's spot" argues for diving in as a single
unit, although a cheap re-entry "tug" device could assist with control in
the IMES scenario.

/dps
  #28  
Old October 28th 11, 03:41 PM posted to sci.space.shuttle
Bob Haller
external usenet poster
 
Posts: 3,197
Default ISS re-entry scenarios (was Dragon to cost about ...)

On Oct 27, 4:38*pm, Snidely wrote:
"Jorge R. Frank" scribbled something like ...

[...] if ISS ends in 2020.


Wandering a bit further afield, have you heard if the simulations show any
difference in how much debris will reach the earth for a whole-ISS entry
interface vs individual modules entering seperately?

I understand that "picking one's spot" argues for diving in as a single
unit, although a cheap re-entry "tug" device could assist with control in
the IMES scenario.

/dps


well a out of control tumbling ISS would likely see structural failure
with ISS shedding modules all along its ground track
  #29  
Old October 29th 11, 02:20 AM posted to sci.space.shuttle
Jorge R. Frank
external usenet poster
 
Posts: 2,089
Default Dragon to cost about $140 million per launch

On 10/27/2011 03:01 PM, Snidely wrote:
"Jorge R. scribbled something like ...

You can't just slap an inert module on the end of a service module and
expect the stack to be controllable. If you look carefully at
Orbital's Cygnus, the pressurized module has RCS clusters arrayed
around the front end. They're fed by propellant lines running *through
the module* to the service module in the aft end.

Ditto the Progress-derived modules and the TKS. They've got RCS
clusters at both ends for controllability.

Bottom line is that the ISS module must be fairly tightly integrated
with the service module.


Seems to me the control-of-jets issue is more important than shared
plumbing. I'd be thinking about 2 "thin" service modules, with either a
wireless connection to a common control port, or a connection that could
use a data bus that would be part of the payload module anyway.


True, but that's not what Jeff was proposing. He was proposing either
Dragon or Cygnus. Dragon doesn't have a service module and Cygnus's
service module isn't "thin" in the sense you're talking about.
  #30  
Old October 29th 11, 02:23 AM posted to sci.space.shuttle
Jorge R. Frank
external usenet poster
 
Posts: 2,089
Default ISS re-entry scenarios (was Dragon to cost about ...)

On 10/27/2011 03:38 PM, Snidely wrote:
"Jorge R. scribbled something like ...
[...] if ISS ends in 2020.


Wandering a bit further afield, have you heard if the simulations show any
difference in how much debris will reach the earth for a whole-ISS entry
interface vs individual modules entering seperately?


Won't make a whole lot of difference; the structure is aluminum and
there is not much "shadowing" effect, especially if the station is
maneuvered to a ZVV attitude after the deorbit burn (which would both
ensure maximum drag and maximum exposure of modules).
 




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