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  #1  
Old August 29th 18, 06:27 PM posted to sci.space.policy
Fred J. McCall[_3_]
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SpaceX will only use brand new Dragon V2 craft for NASA crew missions.
Both SpaceX and Boeing were offered the option of reflying capsules
and Boeing plans to do so, landing on dry land on airbags and then
reflying each of their capsules up to 10 times. SpaceX, however, has
announced that they will only use new spacecraft for NASA crewed
missions (and still compete on costs because Falcon 9 is so much
cheaper than any ULA launcher).

So what happens with all the 'gently used' capsules that will be
stacking up at SpaceX? Apparently the plan is to switch them to cargo
versions and use them to fly ISS resupply missions under the next NASA
Commercial Cargo contract. This will let SpaceX do the cargo launches
for less than half the price of any competitors. Some number of Crew
Dragon could presumably also be used for non-NASA launches.


--
"The reasonable man adapts himself to the world; the unreasonable
man persists in trying to adapt the world to himself. Therefore,
all progress depends on the unreasonable man."
--George Bernard Shaw
  #2  
Old August 30th 18, 06:46 AM posted to sci.space.policy
Fred J. McCall[_3_]
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Default All New For NASA

JF Mezei wrote on Wed, 29 Aug 2018
16:58:39 -0400:

On 2018-08-29 13:27, Fred J. McCall wrote:
SpaceX will only use brand new Dragon V2 craft for NASA crew missions.


How much work is needed to refurb a Dragon V1,0 for reflight? Do they
have to get it back to bare shell and re-insall all components? Or just
pass it through a car wash to remove salt water on the outside and refly it?


Closer to the latter. Given Dragon V1 experience, it will probably
take several months to clean up and test.


For crewed version, after splash down in salt water, will NASA insist on
extracting crews from a floating capsule, or will they lift capsule onto
deck of ship and then open hatch? (aka: salt water ingress).


I think the plan is to pick up capsule, crew, and all and open it up
on deck, but I don't find anything definitive.


Another big variable is ship's "best before" date. A Dragon that has
spent 6 months docked to ISS may require full tear down because many
components are past their "best before" dates.


And monkeys may fly out my butt. They'll need to replenish
consumables plus do cleanup from salt water immersion. There is very
little that rots after 6 months.


It becomes simpler to refit the bare shell as cargo with fewer comonents
that require less testing to recertifty for flight.


That's not how it works. There is a lot of commonality between crewed
and cargo versions.


Also need to look at flight rate. With demand split between 2 suppliers,
SpaceX may have plenty of time to build a new crewed Dragon for each
flight, and if it needs more cargo flights, it makes sense to recycle
the crewed capsule into cargo.


Since their plan is to use a new Crew Dragon for each flight they'd
BETTER have time to get a new one ready.


--
"Some people get lost in thought because it's such unfamiliar
territory."
--G. Behn
  #3  
Old August 30th 18, 12:06 PM posted to sci.space.policy
Jeff Findley[_6_]
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Default All New For NASA

In article ,
says...

SpaceX will only use brand new Dragon V2 craft for NASA crew missions.
Both SpaceX and Boeing were offered the option of reflying capsules
and Boeing plans to do so, landing on dry land on airbags and then
reflying each of their capsules up to 10 times. SpaceX, however, has
announced that they will only use new spacecraft for NASA crewed
missions (and still compete on costs because Falcon 9 is so much
cheaper than any ULA launcher).

So what happens with all the 'gently used' capsules that will be
stacking up at SpaceX? Apparently the plan is to switch them to cargo
versions and use them to fly ISS resupply missions under the next NASA
Commercial Cargo contract. This will let SpaceX do the cargo launches
for less than half the price of any competitors. Some number of Crew
Dragon could presumably also be used for non-NASA launches.


Actually their CRS2 contract is going to cost NASA more money than their
CRS1 contract. But, they're still cheaper than the competition even
with that cost increase. And, as I understand it, Dragon 2 has more
internal volume than Dragon. And because most Dragon flights have been
volume limited (for pressurized cargo), this means NASA will get more
cargo to ISS on fewer Dragon 2 flights than Dragon flights.

All in all, this is a good thing.

Jeff
--
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These posts do not reflect the opinions of my family, friends,
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  #5  
Old August 30th 18, 12:16 PM posted to sci.space.policy
Jeff Findley[_6_]
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Default All New For NASA

In article ,
says...

That's my understanding. Conversion to cargo configuration will involve
taking out the seats, crew consoles, life support, and etc. Essentially
it means unbolting, unplugging, and removing components that simply
aren't needed.

This would be akin to me pulling the middle bad back row seats out of my
2013 Toyota minivan when I need to move things that are long. the
middle row seats are designed to be easily removed. The rear seats,
which can fold down into the floor, can be removed by a determined owner
who has a socket set and maybe an hour's worth of "free time". ;-)


Typo. That should be "middle and back".

With the minivan, it's easier to just rent a U-Haul trailer and pull it
behind when I need a lot of cargo space. For smaller loads, I just pull
the middle seats and leave them in the garage at the house and fold the
rear seats down into the floor.

At any rate, the Sienna can carry 8 passengers or two passengers and a
lot of cargo. It's similar to Dragon 2 in its crew/cargo flexibility.

Jeff
--
All opinions posted by me on Usenet News are mine, and mine alone.
These posts do not reflect the opinions of my family, friends,
employer, or any organization that I am a member of.
  #6  
Old August 30th 18, 03:45 PM posted to sci.space.policy
Alain Fournier[_3_]
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Default All New For NASA

On Aug/30/2018 at 7:16 AM, Jeff Findley wrote :
In article ,
says...

That's my understanding. Conversion to cargo configuration will involve
taking out the seats, crew consoles, life support, and etc. Essentially
it means unbolting, unplugging, and removing components that simply
aren't needed.

This would be akin to me pulling the middle bad back row seats out of my
2013 Toyota minivan when I need to move things that are long. the
middle row seats are designed to be easily removed. The rear seats,
which can fold down into the floor, can be removed by a determined owner
who has a socket set and maybe an hour's worth of "free time". ;-)


Typo. That should be "middle and back".

With the minivan, it's easier to just rent a U-Haul trailer and pull it
behind when I need a lot of cargo space. For smaller loads, I just pull
the middle seats and leave them in the garage at the house and fold the
rear seats down into the floor.

At any rate, the Sienna can carry 8 passengers or two passengers and a
lot of cargo. It's similar to Dragon 2 in its crew/cargo flexibility.


Did you ever test it in a vacuum and with radiations similar to what
there is in LEO? Maybe you're onto something here. :-)


Alain Fournier
  #7  
Old August 30th 18, 05:23 PM posted to sci.space.policy
Fred J. McCall[_3_]
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Posts: 10,018
Default All New For NASA

Jeff Findley wrote on Thu, 30 Aug 2018
07:06:45 -0400:

In article ,
says...

SpaceX will only use brand new Dragon V2 craft for NASA crew missions.
Both SpaceX and Boeing were offered the option of reflying capsules
and Boeing plans to do so, landing on dry land on airbags and then
reflying each of their capsules up to 10 times. SpaceX, however, has
announced that they will only use new spacecraft for NASA crewed
missions (and still compete on costs because Falcon 9 is so much
cheaper than any ULA launcher).

So what happens with all the 'gently used' capsules that will be
stacking up at SpaceX? Apparently the plan is to switch them to cargo
versions and use them to fly ISS resupply missions under the next NASA
Commercial Cargo contract. This will let SpaceX do the cargo launches
for less than half the price of any competitors. Some number of Crew
Dragon could presumably also be used for non-NASA launches.


Actually their CRS2 contract is going to cost NASA more money than their
CRS1 contract.


Yes, I know. But after the price increase they're still estimated to
be 50%-75% cheaper than the competition. I'm sure that if they simply
let to the 'best value' bidder SpaceX would wind up with all the
business. But they have 'no more single point failures' as part of
their objective, so they're going to buy much more expensive launches
to keep the competition in business.


--
"Millions for defense, but not one cent for tribute."
-- Charles Pinckney
  #8  
Old August 30th 18, 05:27 PM posted to sci.space.policy
Fred J. McCall[_3_]
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Posts: 10,018
Default All New For NASA

Jeff Findley wrote on Thu, 30 Aug 2018
07:10:56 -0400:

In article ,
says...

It becomes simpler to refit the bare shell as cargo with fewer comonents
that require less testing to recertifty for flight.


That's not how it works. There is a lot of commonality between crewed
and cargo versions.


That's my understanding. Conversion to cargo configuration will involve
taking out the seats, crew consoles, life support, and etc. Essentially
it means unbolting, unplugging, and removing components that simply
aren't needed.


That's essentially correct. There are also some additions (like
addition of cargo racks, both pressurized and unpressurized). It
apparently looks like this:

https://www.teslarati.com/spacex-no-...modifications/


--
"The reasonable man adapts himself to the world; the unreasonable
man persists in trying to adapt the world to himself. Therefore,
all progress depends on the unreasonable man."
--George Bernard Shaw
  #9  
Old August 30th 18, 05:34 PM posted to sci.space.policy
Fred J. McCall[_3_]
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Posts: 10,018
Default All New For NASA

JF Mezei wrote on Thu, 30 Aug 2018
11:24:52 -0400:

On 2018-08-30 07:10, Jeff Findley wrote:

That's my understanding. Conversion to cargo configuration will involve
taking out the seats, crew consoles, life support, and etc. Essentially
it means unbolting, unplugging, and removing components that simply
aren't needed.


And adding the structural supports for cargo. (aka glorified
shelves/racks or whatever).

However, if the insides of the Dragon are re-usable easily and not
damaged by a flight/landing, why go through the trouble of changing in
inside config from a crewed one proven to work to a cargo one ?


Because there are a lot more cargo flights than crewed flights.


It isn't just the "bolted on" consoles, but also all wiring harnesses.


If the wiring is 'built in' and not just strung all over Hell's half
acre you can just leave it in place after you unplug the consoles.


I wonder if Musk/SpaceX will ever explain what arguments were used to
decide that crewed shouldn't be re-usable as crewed.


Because even flying new they're cheaper than Boeing because Boeing
uses a ULA booster, so they can get NASA to pay to buy the Crew Dragon
new, which subsidizes the cargo side of things.


As far as the heat shield, does SpaceX just "spray" new ablative
material over existing used heat shield to bring it back to proper
thickeness, or does it strip the whole thing out and spray on a totally
new heat shield? Does either change the level of trust in its ability
to support crewed re-entry? (aka: heat shield with new top layer vs
totally new heat shield).


Neither one of those. The heat shield is thick enough to stand
multiple LEO reentries (something like 10) without any maintenance.
Some of it ablates away every flight, but not enough to require
replacement.


--
You have never lived until you have almost died.
Life has a special meaning that the protected
will never know.
  #10  
Old August 31st 18, 03:02 AM posted to sci.space.policy
Greg \(Strider\) Moore
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Posts: 752
Default All New For NASA

"JF Mezei" wrote in message ...

On 2018-08-30 07:10, Jeff Findley wrote:

That's my understanding. Conversion to cargo configuration will involve
taking out the seats, crew consoles, life support, and etc. Essentially
it means unbolting, unplugging, and removing components that simply
aren't needed.


And adding the structural supports for cargo. (aka glorified
shelves/racks or whatever).

However, if the insides of the Dragon are re-usable easily and not
damaged by a flight/landing, why go through the trouble of changing in
inside config from a crewed one proven to work to a cargo one ?

It isn't just the "bolted on" consoles, but also all wiring harnesses.

I wonder if Musk/SpaceX will ever explain what arguments were used to
decide that crewed shouldn't be re-usable as crewed.


NASA is always conservative (other than crewed STS-1 :-)

So my guess is it ultimately came down to: "because we said so" and
everything else was justification for that.

And my guess is after 3-4 flights, NASA will relent and go with a
refurbished crew capsule.


--
Greg D. Moore http://greenmountainsoftware.wordpress.com/
CEO QuiCR: Quick, Crowdsourced Responses. http://www.quicr.net
IT Disaster Response -
https://www.amazon.com/Disaster-Resp...dp/1484221834/

 




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