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* [Starlink] saving ship 20
@ 2022-02-12 17:01 Dave Taht
  2022-02-12 18:36 ` Gary E. Miller
  2022-02-12 21:49 ` David Lang
  0 siblings, 2 replies; 7+ messages in thread
From: Dave Taht @ 2022-02-12 17:01 UTC (permalink / raw)
  To: starlink

(is there a good email list for spacex, rather than starlink stuff?
I'm really not into twitter, reddit, etc)

After watching elon musk's presentation thursday night I was struck by
the symbolism of ship 20 behind him and wondering why the planned
flight was to attempt a splashdown at the end.

https://starshipcampaign.com/starship/ship-20/

I could think of a more leapfrog-like approach where they left it in
orbit, to analyze the effects of a longer term stay there, testing
restarts, or vacuum welding problems on the engines, using as a
agena-like target for rendezvous maneuvers, trying out repairing or
replacing various parts...

Do they not have enough thrust, even with an empty payload bay, to
stay up there?

Is there a dummy payload planned? I was thinking of one of bigalow's
demo inflatable habs, and along that rathole was, why not just cut a
hole in the side and spray in insulation...

Not even sure if there is a working door...

-- 
I tried to build a better future, a few times:
https://wayforward.archive.org/?site=https%3A%2F%2Fwww.icei.org

Dave Täht CEO, TekLibre, LLC

^ permalink raw reply	[flat|nested] 7+ messages in thread

* Re: [Starlink] saving ship 20
  2022-02-12 17:01 [Starlink] saving ship 20 Dave Taht
@ 2022-02-12 18:36 ` Gary E. Miller
  2022-02-12 19:42   ` Dave Taht
  2022-02-12 21:49 ` David Lang
  1 sibling, 1 reply; 7+ messages in thread
From: Gary E. Miller @ 2022-02-12 18:36 UTC (permalink / raw)
  To: starlink

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Yo Dave!

On Sat, 12 Feb 2022 09:01:50 -0800
Dave Taht <dave.taht@gmail.com> wrote:

> (is there a good email list for spacex, rather than starlink stuff?
> I'm really not into twitter, reddit, etc)
> 
> After watching elon musk's presentation thursday night I was struck by
> the symbolism of ship 20 behind him and wondering why the planned
> flight was to attempt a splashdown at the end.

I agree this is not the place, but if not, where?

> I could think of a more leapfrog-like approach where they left it in
> orbit, to analyze the effects of a longer term stay there, testing
> restarts, or vacuum welding problems on the engines, using as a
> agena-like target for rendezvous maneuvers, trying out repairing or
> replacing various parts...

It is very hard to inspecct a booster in space.  One of the big wins for
the returnable rocket has been the after action failure analysis.  You
can see all the things the almost screwed the mission, Then improve them
for the next one.

And, as we have seen many times, getting back in one piece is the hardest
part to get right.

> Do they not have enough thrust, even with an empty payload bay, to
> stay up there?

I'm sure they do, but to stay up they would need a course corrction
or two.

> Is there a dummy payload planned? I was thinking of one of bigalow's
> demo inflatable habs, and along that rathole was, why not just cut a
> hole in the side and spray in insulation...

Maybe another Tesla?

RGDS
GARY
---------------------------------------------------------------------------
Gary E. Miller Rellim 109 NW Wilmington Ave., Suite E, Bend, OR 97703
	gem@rellim.com  Tel:+1 541 382 8588

	    Veritas liberabit vos. -- Quid est veritas?
    "If you can't measure it, you can't improve it." - Lord Kelvin

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^ permalink raw reply	[flat|nested] 7+ messages in thread

* Re: [Starlink] saving ship 20
  2022-02-12 18:36 ` Gary E. Miller
@ 2022-02-12 19:42   ` Dave Taht
  2022-02-12 22:04     ` David Lang
  0 siblings, 1 reply; 7+ messages in thread
From: Dave Taht @ 2022-02-12 19:42 UTC (permalink / raw)
  To: Gary E. Miller; +Cc: starlink

On Sat, Feb 12, 2022 at 10:36 AM Gary E. Miller <gem@rellim.com> wrote:
>
> Yo Dave!
>
> On Sat, 12 Feb 2022 09:01:50 -0800
> Dave Taht <dave.taht@gmail.com> wrote:
>
> > (is there a good email list for spacex, rather than starlink stuff?
> > I'm really not into twitter, reddit, etc)
> >
> > After watching elon musk's presentation thursday night I was struck by
> > the symbolism of ship 20 behind him and wondering why the planned
> > flight was to attempt a splashdown at the end.
>
> I agree this is not the place, but if not, where?

I used to haunt an alt.space list that I can no longer remember the name of.

>
> > I could think of a more leapfrog-like approach where they left it in
> > orbit, to analyze the effects of a longer term stay there, testing
> > restarts, or vacuum welding problems on the engines, using as a
> > agena-like target for rendezvous maneuvers, trying out repairing or
> > replacing various parts...
>
> It is very hard to inspecct a booster in space.  One of the big wins for
> the returnable rocket has been the after action failure analysis.  You
> can see all the things the almost screwed the mission, Then improve them
> for the next one.

Having a pause to inspect the lost tiles, and assess the damage before
even attempting re-entry strikes me as a good idea. I hope they've
lined up some good telescopes this time to take a peek at it. Always
sad we didn't get that done for columbia.

Developing the capability to do on-orbit repair, also is a good goal.

A small robot to do external inspection?

It seems pointless to attempt re-entry if you determined it was going to
fail and seems better to plan on exploring other options.

>
> And, as we have seen many times, getting back in one piece is the hardest
> part to get right.

So why not have a plan B involving staying in orbit, rather than burning up?

>
> > Do they not have enough thrust, even with an empty payload bay, to
> > stay up there?
>
> I'm sure they do, but to stay up they would need a course corrction
> or two.

testing restart seems smart.

> > Is there a dummy payload planned? I was thinking of one of bigalow's
> > demo inflatable habs, and along that rathole was, why not just cut a
> > hole in the side and spray in insulation...
>
> Maybe another Tesla?

Something cheesier than that. But I could envision instruments, at least.
> RGDS
> GARY
> ---------------------------------------------------------------------------
> Gary E. Miller Rellim 109 NW Wilmington Ave., Suite E, Bend, OR 97703
>         gem@rellim.com  Tel:+1 541 382 8588
>
>             Veritas liberabit vos. -- Quid est veritas?
>     "If you can't measure it, you can't improve it." - Lord Kelvin
> _______________________________________________
> Starlink mailing list
> Starlink@lists.bufferbloat.net
> https://lists.bufferbloat.net/listinfo/starlink



-- 
I tried to build a better future, a few times:
https://wayforward.archive.org/?site=https%3A%2F%2Fwww.icei.org

Dave Täht CEO, TekLibre, LLC

^ permalink raw reply	[flat|nested] 7+ messages in thread

* Re: [Starlink] saving ship 20
  2022-02-12 17:01 [Starlink] saving ship 20 Dave Taht
  2022-02-12 18:36 ` Gary E. Miller
@ 2022-02-12 21:49 ` David Lang
  2022-02-12 21:53   ` Nathan Owens
  1 sibling, 1 reply; 7+ messages in thread
From: David Lang @ 2022-02-12 21:49 UTC (permalink / raw)
  To: Dave Taht; +Cc: starlink

On Sat, 12 Feb 2022, Dave Taht wrote:

> (is there a good email list for spacex, rather than starlink stuff?
> I'm really not into twitter, reddit, etc)
>
> After watching elon musk's presentation thursday night I was struck by
> the symbolism of ship 20 behind him and wondering why the planned
> flight was to attempt a splashdown at the end.

they need to test reentry and the heat shield.

> https://starshipcampaign.com/starship/ship-20/
>
> I could think of a more leapfrog-like approach where they left it in
> orbit, to analyze the effects of a longer term stay there, testing
> restarts, or vacuum welding problems on the engines, using as a
> agena-like target for rendezvous maneuvers, trying out repairing or
> replacing various parts...
>
> Do they not have enough thrust, even with an empty payload bay, to
> stay up there?

'space junk', the powers that be frown on putting stuff in orbit. many shuttle 
flights had the delta-v to take the external tanks to orbit, but they 
deliberatly had them burn up instead.

hopefully, once commercial stations become a thing, they will be interested in 
accumulating 2nd stages and other things that we currently are deliberatly 
deorbiting.

> Is there a dummy payload planned? I was thinking of one of bigalow's
> demo inflatable habs, and along that rathole was, why not just cut a
> hole in the side and spray in insulation...
>
> Not even sure if there is a working door...

No door at all on ship 20-24. there is a barrel section that has a door cut in 
it, but that's it so far.

David Lang


^ permalink raw reply	[flat|nested] 7+ messages in thread

* Re: [Starlink] saving ship 20
  2022-02-12 21:49 ` David Lang
@ 2022-02-12 21:53   ` Nathan Owens
  0 siblings, 0 replies; 7+ messages in thread
From: Nathan Owens @ 2022-02-12 21:53 UTC (permalink / raw)
  To: David Lang; +Cc: Dave Taht, starlink

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The top spot to chat about space stuff is Reddit, probably followed by the
NASASpaceFlight Forums, fwiw.

On Sat, Feb 12, 2022 at 1:49 PM David Lang <david@lang.hm> wrote:

> On Sat, 12 Feb 2022, Dave Taht wrote:
>
> > (is there a good email list for spacex, rather than starlink stuff?
> > I'm really not into twitter, reddit, etc)
> >
> > After watching elon musk's presentation thursday night I was struck by
> > the symbolism of ship 20 behind him and wondering why the planned
> > flight was to attempt a splashdown at the end.
>
> they need to test reentry and the heat shield.
>
> > https://starshipcampaign.com/starship/ship-20/
> >
> > I could think of a more leapfrog-like approach where they left it in
> > orbit, to analyze the effects of a longer term stay there, testing
> > restarts, or vacuum welding problems on the engines, using as a
> > agena-like target for rendezvous maneuvers, trying out repairing or
> > replacing various parts...
> >
> > Do they not have enough thrust, even with an empty payload bay, to
> > stay up there?
>
> 'space junk', the powers that be frown on putting stuff in orbit. many
> shuttle
> flights had the delta-v to take the external tanks to orbit, but they
> deliberatly had them burn up instead.
>
> hopefully, once commercial stations become a thing, they will be
> interested in
> accumulating 2nd stages and other things that we currently are deliberatly
> deorbiting.
>
> > Is there a dummy payload planned? I was thinking of one of bigalow's
> > demo inflatable habs, and along that rathole was, why not just cut a
> > hole in the side and spray in insulation...
> >
> > Not even sure if there is a working door...
>
> No door at all on ship 20-24. there is a barrel section that has a door
> cut in
> it, but that's it so far.
>
> David Lang
>
> _______________________________________________
> Starlink mailing list
> Starlink@lists.bufferbloat.net
> https://lists.bufferbloat.net/listinfo/starlink
>

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^ permalink raw reply	[flat|nested] 7+ messages in thread

* Re: [Starlink] saving ship 20
  2022-02-12 19:42   ` Dave Taht
@ 2022-02-12 22:04     ` David Lang
  2022-02-12 23:08       ` Dave Taht
  0 siblings, 1 reply; 7+ messages in thread
From: David Lang @ 2022-02-12 22:04 UTC (permalink / raw)
  To: Dave Taht; +Cc: Gary E. Miller, starlink

On Sat, 12 Feb 2022, Dave Taht wrote:

> Having a pause to inspect the lost tiles, and assess the damage before
> even attempting re-entry strikes me as a good idea. I hope they've
> lined up some good telescopes this time to take a peek at it. Always
> sad we didn't get that done for columbia.

for this first flight, they are deliberatly not going into an orbit that would 
clear the ground (they are going high enough, and fast enough, but not round 
enough), so that they don't need to deal with the complications of a zero-g 
restart (settling the fuel, etc)

They have lined up the NASA aircraft that has a big telescope on it to watch it 
during reentry, and unlike everyone else, they put lots of cameras on and in 
their rockets (spectacular PR and very useful to figure out what went wrong)

Odds are that something will go wrong before reentry on the first flight, but 
they have the timeline go all the way to a landing burn above the ocean, but I 
don't think anyone is expecting it to be intact by the time it spashes down. It 
would be an absolutly spectacular win if it does survive to that point.

> Developing the capability to do on-orbit repair, also is a good goal.
>
> A small robot to do external inspection?
>
> It seems pointless to attempt re-entry if you determined it was going to
> fail and seems better to plan on exploring other options.

until we have a lot more access to space, people are more afraid of 'space junk' 
than interested in accumulating resources in space.

Even if they end up missing some tiles and get a burn-through during reentry, 
it's worth doing the reentry to learn how the skydiver approach works compared 
to what every other spacecraft has done. There has never been anything close to 
this big that's attempted reentry, they don't know how well the computer models 
actually match reality. Given that it will be years before there is manned 
flight that would be able to use it if they left it up there, odds are good that 
it would come down first anyway, just in an uncontrolled fashion.

I'll point out that the bigelow inflatable module on the ISS is only being used 
for storage, NASA doesn't trust inflatables.

>>
>> And, as we have seen many times, getting back in one piece is the hardest
>> part to get right.
>
> So why not have a plan B involving staying in orbit, rather than burning up?

if you never attempt reentry, you can never succeed.

>>
>> > Do they not have enough thrust, even with an empty payload bay, to
>> > stay up there?
>>
>> I'm sure they do, but to stay up they would need a course corrction
>> or two.
>
> testing restart seems smart.

these are gen-1 raptor engines, given how much more complicated they are than 
the gen-2 raptors, how useful would it be? and it would add a LOT of 
complication. Also, unless you boosted it up above the ISS, it will deorbit 
fairly quickly. Starlinks are higher and denser, and they have a lifetime of 5 
years or so without reboost.

David Lang

^ permalink raw reply	[flat|nested] 7+ messages in thread

* Re: [Starlink] saving ship 20
  2022-02-12 22:04     ` David Lang
@ 2022-02-12 23:08       ` Dave Taht
  0 siblings, 0 replies; 7+ messages in thread
From: Dave Taht @ 2022-02-12 23:08 UTC (permalink / raw)
  To: David Lang; +Cc: Gary E. Miller, starlink

thx all. I still think that attempting re-entry with a known-busted
heatshield is kind of a waste, but...

btw, the alt.space mailing list I had been on for a decade or three
(on one of my retired accounts) is "arocket", which has participants
such as henry spencer (https://en.wikipedia.org/wiki/Henry_Spencer),
the original founder of the L5 society, and a few other notables.

https://www.freelists.org/post/arocket/FW-NASA-HQ-News-NASA-Awards-Artemis-Contract-for-Future-Mega-Moon-Rocket-Boosters,3

Just spent an enjoyable hour catching up there.

On Sat, Feb 12, 2022 at 2:04 PM David Lang <david@lang.hm> wrote:
>
> On Sat, 12 Feb 2022, Dave Taht wrote:
>
> > Having a pause to inspect the lost tiles, and assess the damage before
> > even attempting re-entry strikes me as a good idea. I hope they've
> > lined up some good telescopes this time to take a peek at it. Always
> > sad we didn't get that done for columbia.
>
> for this first flight, they are deliberatly not going into an orbit that would
> clear the ground (they are going high enough, and fast enough, but not round
> enough), so that they don't need to deal with the complications of a zero-g
> restart (settling the fuel, etc)
>
> They have lined up the NASA aircraft that has a big telescope on it to watch it
> during reentry, and unlike everyone else, they put lots of cameras on and in
> their rockets (spectacular PR and very useful to figure out what went wrong)
>
> Odds are that something will go wrong before reentry on the first flight, but
> they have the timeline go all the way to a landing burn above the ocean, but I
> don't think anyone is expecting it to be intact by the time it spashes down. It
> would be an absolutly spectacular win if it does survive to that point.
>
> > Developing the capability to do on-orbit repair, also is a good goal.
> >
> > A small robot to do external inspection?
> >
> > It seems pointless to attempt re-entry if you determined it was going to
> > fail and seems better to plan on exploring other options.
>
> until we have a lot more access to space, people are more afraid of 'space junk'
> than interested in accumulating resources in space.
>
> Even if they end up missing some tiles and get a burn-through during reentry,
> it's worth doing the reentry to learn how the skydiver approach works compared
> to what every other spacecraft has done. There has never been anything close to
> this big that's attempted reentry, they don't know how well the computer models
> actually match reality. Given that it will be years before there is manned
> flight that would be able to use it if they left it up there, odds are good that
> it would come down first anyway, just in an uncontrolled fashion.
>
> I'll point out that the bigelow inflatable module on the ISS is only being used
> for storage, NASA doesn't trust inflatables.
>
> >>
> >> And, as we have seen many times, getting back in one piece is the hardest
> >> part to get right.
> >
> > So why not have a plan B involving staying in orbit, rather than burning up?
>
> if you never attempt reentry, you can never succeed.
>
> >>
> >> > Do they not have enough thrust, even with an empty payload bay, to
> >> > stay up there?
> >>
> >> I'm sure they do, but to stay up they would need a course corrction
> >> or two.
> >
> > testing restart seems smart.
>
> these are gen-1 raptor engines, given how much more complicated they are than
> the gen-2 raptors, how useful would it be? and it would add a LOT of
> complication. Also, unless you boosted it up above the ISS, it will deorbit
> fairly quickly. Starlinks are higher and denser, and they have a lifetime of 5
> years or so without reboost.
>
> David Lang



-- 
I tried to build a better future, a few times:
https://wayforward.archive.org/?site=https%3A%2F%2Fwww.icei.org

Dave Täht CEO, TekLibre, LLC

^ permalink raw reply	[flat|nested] 7+ messages in thread

end of thread, other threads:[~2022-02-12 23:08 UTC | newest]

Thread overview: 7+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2022-02-12 17:01 [Starlink] saving ship 20 Dave Taht
2022-02-12 18:36 ` Gary E. Miller
2022-02-12 19:42   ` Dave Taht
2022-02-12 22:04     ` David Lang
2022-02-12 23:08       ` Dave Taht
2022-02-12 21:49 ` David Lang
2022-02-12 21:53   ` Nathan Owens

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