Space Ship achieves powered flight

[Greg (Strider) Moore]

http://www.nytimes.com/2013/04/30/science/space/virgin-galactics-spaceshiptwo-inches-closer-to-space.html?_r=0

Slowly but surely we're getting to more commercialization of space.

[Rick Jones]

"Greg \(Strider\) Moore" <moo...@ignorethisgreenms.com> wrote:
> http://www.nytimes.com/2013/04/30/science/space/virgin-galactics-spaceshiptwo-inches-closer-to-space.html?_r=0

> Slowly but surely we're getting to more commercialization of space.

"He and his children are to be passengers on that first flight. "

OK, I understand there will have been a somewhat full series of tests
before that "first" flight, and that Richard Branson wishes to project
an image of confidence and safety, but still, to take his kids along
with him? Even if they are adults at this point.

rick jones
--
oxymoron n, commuter in a gas-guzzling luxury SUV with an American flag
these opinions are mine, all mine; HP might not want them anyway... :)
feel free to post, OR email to rick.jones2 in hp.com but NOT BOTH...

[David Spain]

On 4/29/2013 6:15 PM, Greg (Strider) Moore wrote:
> http://www.nytimes.com/2013/04/30/science/space/virgin-galactics-spaceshiptwo-inches-closer-to-space.html?_r=0
>
>
> Slowly but surely we're getting to more commercialization of space.

I've become convinced. I *know* the secret doppelganger of Sir Richard
(sans beard and only slightly shorter hair). Put the following links up
side-by-side and tell me I'm wrong! :-)

> http://www.aiai.ed.ac.uk/~bat/GA/IMG/steve-zodiac-original-1.jpg

> http://blogs.villagevoice.com/runninscared/bransonsfpacesuit.png


Dave

[Sylvia Else]

On 30/04/2013 8:15 AM, Greg (Strider) Moore wrote:
> http://www.nytimes.com/2013/04/30/science/space/virgin-galactics-spaceshiptwo-inches-closer-to-space.html?_r=0
>
>
> Slowly but surely we're getting to more commercialization of space.

I'll believe that when I see such a craft do an orbit.

Sylvia.

[Greg (Strider) Moore]

>"David Spain" wrote in message
>news:p5-dnWIVTq_uY-PM...@giganews.com...

Hah. You're right!


>
>Dave
>
>

--
Greg D. Moore http://greenmountainsoftware.wordpress.com/
CEO QuiCR: Quick, Crowdsourced Responses. http://www.quicr.net

[Greg (Strider) Moore]

"Sylvia Else" wrote in message news:au9k9q...@mid.individual.net...

Huh?

That makes absolutely no sense. SS2 isn't designed to go into orbit.

And if you want a commercial designed craft that IS designed to go to orbit,
I present to you Dragon. Which has not only gone to orbit, but flown to the
Space Station and returned cargo.

So your comment makes no sense. We already HAVE commercialization of space.
We're now getting more.


>
>Sylvia.

[Jochem Huhmann]

"Greg (Strider) Moore" <moo...@ignorethisgreenms.com> writes:

> That makes absolutely no sense. SS2 isn't designed to go into orbit.
>
> And if you want a commercial designed craft that IS designed to go to
> orbit, I present to you Dragon. Which has not only gone to orbit, but
> flown to the Space Station and returned cargo.
>
> So your comment makes no sense. We already HAVE commercialization of
> space. We're now getting more.

She's right though. "Space" may begin at 100 km, but hopping up and down
isn't "going to space" in any meaningful way. It's more
commercialization of high-end joyrides than commercialization of space.


Jochem

--
"A designer knows he has arrived at perfection not when there is no
longer anything to add, but when there is no longer anything to take away."
- Antoine de Saint-Exupery

[Jeff Findley]

In article <au9k9q...@mid.individual.net>,
syl...@not.at.this.address says...

It won't be so many years and we should see commercial crew for ISS. If
SpaceX is also successful with its initiatives to reuse Falcon 9 and
Dragon, prices will drop enough that I'm quite certain we'll see them
operating to/from a commercial Bigelow space station as well as ISS.

There is a long way to go but we're finally seeing progress.

Jeff
--
"the perennial claim that hypersonic airbreathing propulsion would
magically make space launch cheaper is nonsense -- LOX is much cheaper
than advanced airbreathing engines, and so are the tanks to put it in
and the extra thrust to carry it." - Henry Spencer

[bob haller]

> She's right though. "Space" may begin at 100 km, but hopping up and down
> isn't "going to space" in any meaningful way. It's more
> commercialization of high-end joyrides than commercialization of space.
>
>         Jochem

tourism is a major industry, so hopper flights to near earth orbit is
a affordable stepping stone. and may well lead to airline like travel
new york to paris in 1.5 hours......

[Vaughn]

On 4/30/2013 8:08 AM, Greg (Strider) Moore wrote:
> "Sylvia Else" wrote in message news:au9k9q...@mid.individual.net...
>>
>> On 30/04/2013 8:15 AM, Greg (Strider) Moore wrote:
>>> http://www.nytimes.com/2013/04/30/science/space/virgin-galactics-spaceshiptwo-inches-closer-to-space.html?_r=0
>>>
>>>
>>>
>>> Slowly but surely we're getting to more commercialization of space.
>>
>> I'll believe that when I see such a craft do an orbit.
>
> Huh?
>
> That makes absolutely no sense.

That's strange, because it makes perfect sense to me. SS2 is only
designed to make very brief forays slightly above the arbitrary
human-defined 100 km limit of space. SS2 is a neat toy, it represents a
genuine advance to the state of aeronautical art, and it may even
generate profits, but human space travel it ain't.

Vaughn

[Jochem Huhmann]

But this isn't about orbit at all and this thing travels some dozens of
miles at best.

It's orders of magnitude away from orbit or some suborbital
intercontinental flight. It's hardly more than a stunt and there is no
way to go from this to what achieving orbit would require with any of
the technologies it uses. It's a first step to orbit as jumping up and
down is a first step to flying.

I mean, I wish them all the best, but this is not space tourism. Not if
you're "in space" for 15 minutes or so.

[Jeff Findley]

In article <m261z4x...@revier.com>, j...@gmx.net says...

>
> "Greg (Strider) Moore" <moo...@ignorethisgreenms.com> writes:
>
> > That makes absolutely no sense. SS2 isn't designed to go into orbit.
> >
> > And if you want a commercial designed craft that IS designed to go to
> > orbit, I present to you Dragon. Which has not only gone to orbit, but
> > flown to the Space Station and returned cargo.
> >
> > So your comment makes no sense. We already HAVE commercialization of
> > space. We're now getting more.
>
> She's right though. "Space" may begin at 100 km, but hopping up and down
> isn't "going to space" in any meaningful way. It's more
> commercialization of high-end joyrides than commercialization of space.

While SS2 will never make orbit, it will help to prove if there is a
"big enough" market for (still quite expensive) flights into space. If
there aren't enough customers who want to shell out $200k for a flight
on SS2, how big could the market be for tickets to orbit that are at
least 10x that price?

Note that I'm guessing on the multiplier here on the assumption that
SpaceX can reuse Dragons and reuse at least the first stage of Falcon 9.
Still, I'm quite hopeful that they can get the price per seat well below
what the Russians currently charge on their entirely expendable Soyuz
launch vehicle and Soyuz spacecraft.

[Jeff Findley]

In article <fcd4133c-2152-4206-8da5-f60f705b3029
@i2g2000yqf.googlegroups.com>, hal...@aol.com says...

>
> > She's right though. "Space" may begin at 100 km, but hopping up and down
> > isn't "going to space" in any meaningful way. It's more
> > commercialization of high-end joyrides than commercialization of space.
>

> tourism is a major industry, so hopper flights to near earth orbit is
> a affordable stepping stone.

Tourism is a major industry, but *space* tourism is virtually non-
existent at this time. It remains to be seen if Virgin Galactic will be
able to make money from SS2. The market may, or may not, materialize.

In other words, "build it and they will come" is not always true.

> and may well lead to airline like travel
> new york to paris in 1.5 hours......

SS2 will do no such thing. It's flight trajectory is not optimized for
distance, it's optimized for height. A trajectory that is not optimized
for distance would likely lead to a vehicle design far different than
SS2.

[Jeff Findley]

In article <klojrr$h3n$1...@speranza.aioe.org>, vaugh...@gmail.com
says...

I think of it as being akin to a sightseeing bus or boat that makes no
stops. The tourists still get to see everything out the window of the
bus, but they don't get off the vehicle until it arrives back at its
starting point.

When we were tourists in New York City, we paid to take a boat tour
around the island of Manhattan. It was a "non-stop" boat tour. I
consider that tourism.

[Jochem Huhmann]

Jeff Findley <jeff.f...@nospam.ugs.com> writes:

> While SS2 will never make orbit, it will help to prove if there is a
> "big enough" market for (still quite expensive) flights into space. If
> there aren't enough customers who want to shell out $200k for a flight
> on SS2, how big could the market be for tickets to orbit that are at
> least 10x that price?

Hard to say. I mean, you can't compare both anyway. One is a joyride
that lasts a few hours, most of which will look and feel like flying in
an airplane (because it's exactly that) with 20 minutes of
weightlessness thrown in. It's not a flight into space in any way.

The other is going to space for days or weeks, floating around and looking
at Earth rotating beneath. Paying ten times as much for getting hundreds
times more is certainly cheap.

[Jeff Findley]

In article <m21u9sx...@revier.com>, j...@gmx.net says...

>
> bob haller <hal...@aol.com> writes:
>
> >> She's right though. "Space" may begin at 100 km, but hopping up and down
> >> isn't "going to space" in any meaningful way. It's more
> >> commercialization of high-end joyrides than commercialization of space.
> >>

> >> ￜ ￜ ￜ ￜ Jochem

> >
> > tourism is a major industry, so hopper flights to near earth orbit is
> > a affordable stepping stone. and may well lead to airline like travel
> > new york to paris in 1.5 hours......
>
> But this isn't about orbit at all and this thing travels some dozens of
> miles at best.
>
> It's orders of magnitude away from orbit or some suborbital
> intercontinental flight. It's hardly more than a stunt and there is no
> way to go from this to what achieving orbit would require with any of
> the technologies it uses. It's a first step to orbit as jumping up and
> down is a first step to flying.
>
> I mean, I wish them all the best, but this is not space tourism. Not if
> you're "in space" for 15 minutes or so.

I disagree.

If what you say is true, then the boat tour my family took around
Manhattan wasn't "tourism" because we didn't stop until we were back at
our starting point. That's utter b.s. because we did get to see all the
sights we wanted to see. We didn't pick a tour that stopped anywhere
(e.g. Ellis Island) because the weather was inclement that day. We were
still tourists paying for a relatively short sight seeing trip.

[Greg (Strider) Moore]

"Jochem Huhmann" wrote in message news:m261z4x...@revier.com...

>
>"Greg (Strider) Moore" <moo...@ignorethisgreenms.com> writes:
>
>> That makes absolutely no sense. SS2 isn't designed to go into orbit.
>>
>> And if you want a commercial designed craft that IS designed to go to
>> orbit, I present to you Dragon. Which has not only gone to orbit, but
>> flown to the Space Station and returned cargo.
>>
>> So your comment makes no sense. We already HAVE commercialization of
>> space. We're now getting more.
>
>She's right though. "Space" may begin at 100 km, but hopping up and down
>isn't "going to space" in any meaningful way. It's more
>commercialization of high-end joyrides than commercialization of space.

It's space. It's commercial. So what if it's only joy-rides?

The folks paying know what they're buying and seem quite happy with that.


>
>
> Jochem

[Jeff Findley]

In article <m2wqrkv...@revier.com>, j...@gmx.net says...

>
> Jeff Findley <jeff.f...@nospam.ugs.com> writes:
>
> > While SS2 will never make orbit, it will help to prove if there is a
> > "big enough" market for (still quite expensive) flights into space. If
> > there aren't enough customers who want to shell out $200k for a flight
> > on SS2, how big could the market be for tickets to orbit that are at
> > least 10x that price?
>
> Hard to say. I mean, you can't compare both anyway. One is a joyride
> that lasts a few hours, most of which will look and feel like flying in
> an airplane (because it's exactly that) with 20 minutes of
> weightlessness thrown in. It's not a flight into space in any way.

Yet in the early days of aviation, people *did* pay for short flights in
an airplane that landed at the same place they took off.

[Greg (Strider) Moore]

"Vaughn" wrote in message news:klojrr$h3n$1...@speranza.aioe.org...

Well, no wonder it makes sense to you. You're obviously reading something I
didn't write.

I didn't say "space travel" I said commercialization of space.

Not all commercialization of space is space travel any more than
commercialization of the seas are trans-oceanic ocean liners or even cruise
ships.


>
>Vaughn

[Jochem Huhmann]

Jeff Findley <jeff.f...@nospam.ugs.com> writes:
>> and may well lead to airline like travel
>> new york to paris in 1.5 hours......
>
> SS2 will do no such thing. It's flight trajectory is not optimized for
> distance, it's optimized for height. A trajectory that is not optimized
> for distance would likely lead to a vehicle design far different than
> SS2.

It also lacks the energy, mass ratio and heat shield (for reentry) to do
anything like that. Even if optimized for distance instead of height
you'd get only a very short distance out of it.

And even a suborbital intercontinental flight would take you to much
greater heights than what SS2 achieves. An ICBM is at about 1200 km at
apogee.

[Jochem Huhmann]

"Greg (Strider) Moore" <moo...@ignorethisgreenms.com> writes:

>>She's right though. "Space" may begin at 100 km, but hopping up and down
>> isn't "going to space" in any meaningful way. It's more
>> commercialization of high-end joyrides than commercialization of
>> space.
>
> It's space. It's commercial. So what if it's only joy-rides?
>
> The folks paying know what they're buying and seem quite happy with that.

Nothing wrong with that, but lumping it in with spaceflight (which is
much harder to do and a totally different thing) just because it touches
space for a moment isn't very wise.

If those people having payed a deposit suddenly don't want to fly and
the thing tanks, are you going to say "It has been proven that space
tourism isn't viable"?

I mean, I would pay lots for being a week in orbit but I sure as
wouldn't pay $200k for such a joyride.

[Jochem Huhmann]

Jeff Findley <jeff.f...@nospam.ugs.com> writes:

> If what you say is true, then the boat tour my family took around
> Manhattan wasn't "tourism" because we didn't stop until we were back at
> our starting point. That's utter b.s. because we did get to see all the
> sights we wanted to see. We didn't pick a tour that stopped anywhere
> (e.g. Ellis Island) because the weather was inclement that day. We were
> still tourists paying for a relatively short sight seeing trip.

I still don't think a journey that takes you to space for ten or twenty
minutes counts as "space tourism".

OK, you can call it that if you want to, but alone the fact that going
to orbit and hopping up to 100 km are orders of magnitude apart from an
energy POV seems to suggest that using different names for different
things is the right thing to do.

[David Spain]

On 4/30/2013 8:44 AM, Jeff Findley wrote:
> It won't be so many years and we should see commercial crew for ISS. If
> SpaceX is also successful with its initiatives to reuse Falcon 9 and
> Dragon, prices will drop enough that I'm quite certain we'll see them
> operating to/from a commercial Bigelow space station as well as ISS.
>
> There is a long way to go but we're finally seeing progress.

I'm still intrigued about the type of flight profile SpaceX plans to use
for a reusable Falcon 9 first stage.

So far everything I've seen seems to plan out for a nearly vertical
trajectory for the first stage. The reason I suspect this so strongly is
not just the "grasshopper" tests, but the lack of infrastructure
investment on the part of SpaceX along the Atlantic or Pacific coastal
routes that Falcon 9 will likely fly.

In order to preserve a fair amount of downrange you'd want to have at
least purchased a site along the flight path that would allow the stage
to return along the parabolic in order to keep the maneuvers needed to
be as simple as possible. A small arc at apogee translates into hundreds
of miles downrange at the landing site. But I've seen no such activity.
Either east of Florida or south of California.

Assuming they are not intending to water ditch (why bother with landing
gear in that case?) then we are left with only a nearly vertical
up-and-down trajectory that allows a first stage RTLS.

This puts much more burden than currently exists on the second stage to
get the capsule into an orbital trajectory. The SpaceX video shows plans
for a recoverable 2nd stage as well, but I wonder if at least initially
they would plan to keep this disposable at least at the beginning. Here
the expense is only tanks and *one* engine, so the loss is not as
severe. Also note that all plans show the solar paneled Dragon "trunk"
as non-recoverable.

We have not yet seen Falcon 9 fly such a profile as the one needed for
recovery of the first stage. But I believe it will be essential in
getting the cost down into the range the Musk believes will put SpaceX
ahead of the rest. The question is who is willing to be the first to
actually want to pay to try that? Is NASA on board with that? It's
really not needed for the missions they want to fly since they have the
$$$ on hand to continue business-as-usual... We live in interesting times...

Dave

[David Spain]

On 4/30/2013 1:01 PM, Jochem Huhmann wrote:
> I still don't think a journey that takes you to space for ten or twenty
> minutes counts as "space tourism".
>
> OK, you can call it that if you want to, but alone the fact that going
> to orbit and hopping up to 100 km are orders of magnitude apart from an
> energy POV seems to suggest that using different names for different
> things is the right thing to do.

But good enough for the pilots at least to be considered astronauts.

FWIW back in the late 50's and early 60's the USAF was handing out
astronaut wings to X-15 pilots, for flying a craft which did nearly the
same thing as SS-1 / SS-2...


Dave

[Rick Jones]

Call it "space storming" or some such a la barn storming. I suspect
the effect on "space tourism" will be about the same as barn
storming's on "air tourism."

rick jones
--
Don't anthropomorphize computers. They hate that. - Anonymous

[Rick Jones]

Jochem Huhmann <j...@gmx.net> wrote:
> Hard to say. I mean, you can't compare both anyway. One is a joyride
> that lasts a few hours, most of which will look and feel like flying
> in an airplane (because it's exactly that) with 20 minutes of
> weightlessness thrown in. It's not a flight into space in any way.

The stories I have seen have been quoting 6 minutes of weightlessness.
Or perhaps 6 minutes of "free floating" (out of one's seat)
weightlessness.

rick jones
--
a wide gulf separates "what if" from "if only"

[Jeff Findley]

In article <Sf2dnX1aXJflZuLM...@giganews.com>, nospam@
127.0.0.1 says...

What you're missing in all of this is that Falcon 9 has become Falcon
v1.1 (or whatever SpaceX is calling it). The upgraded version has
higher thrust Merlin engines and stretched tanks. But, they're still
going to use it to place (roughly) the same payload into orbit.
Therefore, they have ample performance margin to play with.

On the first flight of the new vehicle, they plan on simulating a
landing of the first stage. Now this will happen over the ocean, so
it's not going to have landing gear, but it will simulate the flight
trajectory of a returning stage.

A traditional aerospace approach would be to use the additional
performance to put additional payload into orbit. But from Musk's point
of view, that is terribly short sighted. If he's able to reuse that
higher performance first stage, the "lost payload opportunity" will
actually become a "first stage reuse opportunity". That is key to
reducing costs long term.

An incremental increase of Falcon 9 payload to orbit is not in their
long term interests. This is especially true when you consider they're
working on Falcon Heavy to obtain *far* bigger payload increases than
could be had with the Falcon 9 configuration. Add to that the
possibility of reusing Falcon Heavy stages (perhaps only the outer
boosters) and you have the beginnings of a family of reusable launch
vehicles.

The approach SpaceX is taking needs to be considered in its totality.
Myopically focusing on one aspect of their approach can quickly lead you
astray.

[Jochem Huhmann]

David Spain <nos...@127.0.0.1> writes:

> On 4/30/2013 8:44 AM, Jeff Findley wrote:
>> It won't be so many years and we should see commercial crew for ISS. If
>> SpaceX is also successful with its initiatives to reuse Falcon 9 and
>> Dragon, prices will drop enough that I'm quite certain we'll see them
>> operating to/from a commercial Bigelow space station as well as ISS.
>>
>> There is a long way to go but we're finally seeing progress.
>
> I'm still intrigued about the type of flight profile SpaceX plans to use
> for a reusable Falcon 9 first stage.

I was wondering the very same things, but it seems SpaceX indeed wants
to fly the thing back to the launch site under power. This will need
quite a bit of propellants, but then the Falcon 9 1.1 has stretched
tanks, more powerful engines and will still launch the same payload
(when carrying Dragon), so it may work out. If it does this will mean
dealing the cost of additional fuel/oxidizer against getting back the
first stage right at the launch site. Which is a good deal.

> We have not yet seen Falcon 9 fly such a profile as the one needed for
> recovery of the first stage. But I believe it will be essential in
> getting the cost down into the range the Musk believes will put SpaceX
> ahead of the rest. The question is who is willing to be the first to
> actually want to pay to try that? Is NASA on board with that? It's
> really not needed for the missions they want to fly since they have the
> $$$ on hand to continue business-as-usual... We live in interesting
> times...

AFAIK the next Falcon launch already will be a Falcon 9 1.1 and the next
Grasshopper will be based on the 1.1 first stage. Seems to be fairly
obvious where this is going.

I'm still wondering how they want to get the first stage down without
tumbling and tearing it into scrap (it's not exactly aerodynamically
stable with most of the mass at the back, this thing will be desperately
trying to fly backwards without some active control).

[Jeff Findley]

In article <klov6b$eos$2...@usenet01.boi.hp.com>, rick....@hp.com
says...

>
> Jochem Huhmann <j...@gmx.net> wrote:
> > Hard to say. I mean, you can't compare both anyway. One is a joyride
> > that lasts a few hours, most of which will look and feel like flying
> > in an airplane (because it's exactly that) with 20 minutes of
> > weightlessness thrown in. It's not a flight into space in any way.
>
> The stories I have seen have been quoting 6 minutes of weightlessness.
> Or perhaps 6 minutes of "free floating" (out of one's seat)
> weightlessness.

Plus the view out of the windows. You're not going to get that view
from a jet powered "vomit comet" type of aircraft flying parabolas.

Is that going to be worth $200k? I personally wouldn't know, because
I'll never have that kind of money to spend on tourism, a thrill ride,
or whatever you want to call it. I will note that during aviation's
early days, only the very rich could afford to travel long distance by
air. The masses, like me, could only afford to travel long distance by
train and/or ship.

[Jeff Findley]

In article <m2fvy7x...@revier.com>, j...@gmx.net says...

>
> David Spain <nos...@127.0.0.1> writes:
>
> > On 4/30/2013 8:44 AM, Jeff Findley wrote:
> >> It won't be so many years and we should see commercial crew for ISS. If
> >> SpaceX is also successful with its initiatives to reuse Falcon 9 and
> >> Dragon, prices will drop enough that I'm quite certain we'll see them
> >> operating to/from a commercial Bigelow space station as well as ISS.
> >>
> >> There is a long way to go but we're finally seeing progress.
> >
> > I'm still intrigued about the type of flight profile SpaceX plans to use
> > for a reusable Falcon 9 first stage.
>
> I was wondering the very same things, but it seems SpaceX indeed wants
> to fly the thing back to the launch site under power. This will need
> quite a bit of propellants, but then the Falcon 9 1.1 has stretched
> tanks, more powerful engines and will still launch the same payload
> (when carrying Dragon), so it may work out. If it does this will mean
> dealing the cost of additional fuel/oxidizer against getting back the
> first stage right at the launch site. Which is a good deal.

SpaceX has said the cost of propellants is less than 1% of the total
launch costs. So yes, it's a good deal indeed!

> > We have not yet seen Falcon 9 fly such a profile as the one needed
for
> > recovery of the first stage. But I believe it will be essential in
> > getting the cost down into the range the Musk believes will put SpaceX
> > ahead of the rest. The question is who is willing to be the first to
> > actually want to pay to try that? Is NASA on board with that? It's
> > really not needed for the missions they want to fly since they have the
> > $$$ on hand to continue business-as-usual... We live in interesting
> > times...
>
> AFAIK the next Falcon launch already will be a Falcon 9 1.1 and the next
> Grasshopper will be based on the 1.1 first stage. Seems to be fairly
> obvious where this is going.
>
> I'm still wondering how they want to get the first stage down without
> tumbling and tearing it into scrap (it's not exactly aerodynamically
> stable with most of the mass at the back, this thing will be desperately
> trying to fly backwards without some active control).

They intend to "land" the first stage on the first v1.1 flight in the
ocean. In other words, simulate the trajectory of a "land landing".
This will aid them in their learning curve. This isn't anything
terribly new. DC-X/XA did much the same thing, at a smaller scale.

[Rick Jones]

Jochem Huhmann <j...@gmx.net> wrote:
> I'm still wondering how they want to get the first stage down
> without tumbling and tearing it into scrap (it's not exactly
> aerodynamically stable with most of the mass at the back, this thing
> will be desperately trying to fly backwards without some active
> control).

Isn't all the Grasshopper work testing of some active control? Put a
little spin on it after separation and let the thing coast to apogee
and then pop a drogue out the top?-)

How much mass will there be in each of the tanks at separation? Will
that be the point at which it is most desperate to fly backwards? As
they get closer to landing, presumably going slower and slower, will
it be any less desperate?

rick jones
--
"You can't do a damn thing in this house without having to do three
other things first!" - my father (It seems universally applicable :)

[Jochem Huhmann]

Jeff Findley <jeff.f...@nospam.ugs.com> writes:

> They intend to "land" the first stage on the first v1.1 flight in the
> ocean. In other words, simulate the trajectory of a "land landing".
> This will aid them in their learning curve. This isn't anything
> terribly new. DC-X/XA did much the same thing, at a smaller scale.

Certainly a good idea. But I'm still a bit confused about flying an
empty rocket stage that consists of lightweight tanks in the front and
heavy engines and thrust structure at the back without any kind of wings
or active control into denser atmosphere without having it turn around
and break apart. This is not easy, I think.

[Jochem Huhmann]

Rick Jones <rick....@hp.com> writes:

> Jochem Huhmann <j...@gmx.net> wrote:
>> I'm still wondering how they want to get the first stage down
>> without tumbling and tearing it into scrap (it's not exactly
>> aerodynamically stable with most of the mass at the back, this thing
>> will be desperately trying to fly backwards without some active
>> control).
>
> Isn't all the Grasshopper work testing of some active control? Put a
> little spin on it after separation and let the thing coast to apogee
> and then pop a drogue out the top?-)

The question is if the engine (or an RCS) is going to give you enough
control over it to keep it pointing the nose into the wind. This is very
much like throwing a dart backwards with the fins pointing forward.

But all of this depends heavily on the actual trajectory of the first
stage. If they manage to fly it back while still out of the dense
atmosphere and then let the atmosphere brake it when it already is very
near the landing site, all of this is moot. Then it will more or less
just fall towards the landing site and all you need to do is orient it
engine down and steer it towards the pad.

> How much mass will there be in each of the tanks at separation? Will
> that be the point at which it is most desperate to fly backwards? As
> they get closer to landing, presumably going slower and slower, will
> it be any less desperate?

At the point of landing you will want to have it flying backwards
anyway, you don't want to land it onto the nose ;-)

[bob haller]

>
> The stories I have seen have been quoting 6 minutes of weightlessness.
> Or perhaps 6 minutes of "free floating" (out of one's seat)
> weightlessness.
>
> rick jones

zero G makes many people ill. so a short jaunt can weed out those who
may want to avoid throwing up for 3 days:)

[Snidely]

Jeff Findley scribbled something on Tuesday the 30th:

> Is that going to be worth $200k? I personally wouldn't know, because
> I'll never have that kind of money to spend on tourism, a thrill ride,
> or whatever you want to call it. I will note that during aviation's
> early days, only the very rich could afford to travel long distance by
> air. The masses, like me, could only afford to travel long distance by
> train and/or ship.

You reminded me of the last story in _The Man Who Sold The Moon_.

/dps

--
Who, me? And what lacuna?

[Robert Love]

On 2013-04-30 15:34:19 +0000, Jochem Huhmann said:
>
> Hard to say. I mean, you can't compare both anyway. One is a joyride
> that lasts a few hours, most of which will look and feel like flying in
> an airplane (because it's exactly that) with 20 minutes of
> weightlessness thrown in. It's not a flight into space in any way.

I hate to cite mindless television as the right answer but "a 3 hour
tour" that is, 2 orbits. That's what I'd call a space tour. A
suborbital hop would never get my money.

2 orbits is short enough that you don't have to serve food and with
preparation, you don't have to have a toilet. You can't hold it 3
hours, you can't fly.

2 orbits is long enough to see day and night sides of earth, maybe
aurora and then check out favorites again on the next orbit.

[Jochem Huhmann]

The first one or two days are the worst, it usually gets better then. 6
minutes probably is just enough to feel uneasy, vomit once or twice and
then it's over ;-)

[Sylvia Else]

On 30/04/2013 10:08 PM, Greg (Strider) Moore wrote:
> "Sylvia Else" wrote in message news:au9k9q...@mid.individual.net...
>>
>> On 30/04/2013 8:15 AM, Greg (Strider) Moore wrote:
>>> http://www.nytimes.com/2013/04/30/science/space/virgin-galactics-spaceshiptwo-inches-closer-to-space.html?_r=0
>>>
>>>
>>>
>>> Slowly but surely we're getting to more commercialization of space.
>>
>> I'll believe that when I see such a craft do an orbit.
>
> Huh?
>

>SS2 isn't designed to go into orbit.

My point.

Sylvia.

[Jeff Findley]

In article <22d7ed38-fb97-4d9f-a490-784ee07a7778
@d6g2000yqi.googlegroups.com>, hal...@aol.com says...

I doubt that a few minutes in zero gravity is going to "weed out" many
people. That time is so short and the cabin of SS2 is so small, it's
doubtful they would become terribly disoriented in such a short period
of time.

To support your assertion, you'd have to provide a link to a study which
attempted to correlate astronauts getting sick on the Vomit Comet and
those getting true "space sickness" in orbit.

[Jeff Findley]

In article <m2bo8vx...@revier.com>, j...@gmx.net says...

>
> Jeff Findley <jeff.f...@nospam.ugs.com> writes:
> > They intend to "land" the first stage on the first v1.1 flight in the
> > ocean. In other words, simulate the trajectory of a "land landing".
> > This will aid them in their learning curve. This isn't anything
> > terribly new. DC-X/XA did much the same thing, at a smaller scale.
>
> Certainly a good idea. But I'm still a bit confused about flying an
> empty rocket stage that consists of lightweight tanks in the front and
> heavy engines and thrust structure at the back without any kind of wings
> or active control into denser atmosphere without having it turn around
> and break apart. This is not easy, I think.

I majored in Dynamics and Control when I got my B.S. in Aerospace
Engineering at Purdue and I can tell you with certainty that active
control systems rock.

[Jeff Findley]

In article <m27gjjx...@revier.com>, j...@gmx.net says...

These are all "details" which are going to be worked out during testing.

Computer simulations are a good thing (I write engineering software for
a living). But, there really is no substitute for testing the real
thing in the real world. Real world testing often reveals issues that
the computer simulations missed. As a software developer, I'd like to
note that even if the computer software is "perfect", if the input isn't
perfect, the simulation will suffer from the dreaded "garbage in,
garbage out" principle.

This is precisely why SpaceX will have the first stage on the next
flight start testing how to land the thing. Doing this over the ocean
seems like a great idea, since on an expendable you've got to clear the
area anyway. It will cost them very little to perform these sorts of
tests.

[Jochem Huhmann]

Jeff Findley <jeff.f...@nospam.ugs.com> writes:

> In article <m2bo8vx...@revier.com>, j...@gmx.net says...
>>
>> Jeff Findley <jeff.f...@nospam.ugs.com> writes:
>> > They intend to "land" the first stage on the first v1.1 flight in the
>> > ocean. In other words, simulate the trajectory of a "land landing".
>> > This will aid them in their learning curve. This isn't anything
>> > terribly new. DC-X/XA did much the same thing, at a smaller scale.
>>
>> Certainly a good idea. But I'm still a bit confused about flying an
>> empty rocket stage that consists of lightweight tanks in the front and
>> heavy engines and thrust structure at the back without any kind of wings
>> or active control into denser atmosphere without having it turn around
>> and break apart. This is not easy, I think.
>
> I majored in Dynamics and Control when I got my B.S. in Aerospace
> Engineering at Purdue and I can tell you with certainty that active
> control systems rock.

They will need to rock quite a bit to control a lightweight aluminum
can with its center of gravity at the rear. And this needs some powerful
RCS and fuel for it of course.

Anyway, I'm certain SpaceX wouldn't go forward with this without having
found that they can make it work. I'm just curious about the actual
trajectory of the first stage and flight profile for the return leg.

[Jeff Findley]

In article <m2y5byv...@revier.com>, j...@gmx.net says...

>
> Jeff Findley <jeff.f...@nospam.ugs.com> writes:
>
> > In article <m2bo8vx...@revier.com>, j...@gmx.net says...
> >>
> >> Jeff Findley <jeff.f...@nospam.ugs.com> writes:
> >> > They intend to "land" the first stage on the first v1.1 flight in the
> >> > ocean. In other words, simulate the trajectory of a "land landing".
> >> > This will aid them in their learning curve. This isn't anything
> >> > terribly new. DC-X/XA did much the same thing, at a smaller scale.
> >>
> >> Certainly a good idea. But I'm still a bit confused about flying an
> >> empty rocket stage that consists of lightweight tanks in the front and
> >> heavy engines and thrust structure at the back without any kind of wings
> >> or active control into denser atmosphere without having it turn around
> >> and break apart. This is not easy, I think.
> >
> > I majored in Dynamics and Control when I got my B.S. in Aerospace
> > Engineering at Purdue and I can tell you with certainty that active
> > control systems rock.
>
> They will need to rock quite a bit to control a lightweight aluminum
> can with its center of gravity at the rear. And this needs some powerful
> RCS and fuel for it of course.

Possibly. Testing will tell SpaceX if the trajectory they envision is
going to work with the control system, RCS, and center Merlin engine.
They have not published details. These sorts of details are no doubt
going to be trade secrets for as long as SpaceX can keep them secret.
They've already been going down the trade secret route (versus patents).
There have been articles about this in the media.

ELON MUSK: 'If We Published Patents, It Would Be Farcical'

Read more: http://www.businessinsider.com/elon-musk-patents-2012-11
#ixzz2S34Nl2l9

http://www.businessinsider.com/elon-musk-patents-2012-11


So pretty much any discussion here will involve massive speculation. As
such, I'll be waiting to hear what SpaceX has to say (and show) about
their tests. Publishing Grasshopper videos and pictures doesn't reveal
much. It's so close to DC-X that there really aren't any trade secrets
there. But it would not surprise me if SpaceX does *not* release the
complete video of the attempted "landings" of Falcon 9 first stages.
The trajectory, and techniques to control it, leading up to the final
landing stage (i.e. what Grasshopper does), might very well be
considered a trade secret. I'm guessing if it is successful, we'll only
see video of the final descent.

> Anyway, I'm certain SpaceX wouldn't go forward with this
> without having found that they can make it work. I'm just
> curious about the actual trajectory of the first stage
> and flight profile for the return leg.

True, at least in simulation. But real world testing is the only way to
prove that it will work. The philosophy of "test early and often" is
being applied here. It's a great way to make progress quickly, but it
does involve risk. But the strategy of testing first stage "landings"
on the ocean is a good one. If it fails, it does *not* impact the
mission in any way, shape, or form, so the risk to the mission is
mitigated.

[Rick Jones]

Jeff Findley <jeff.f...@nospam.ugs.com> wrote:
> Doing this over the ocean seems like a great idea, since on an
> expendable you've got to clear the area anyway.

I'd think that one would have to clear the area whether it is an
expendable or not - there is the hopefully rather small chance of a
loss of vehicle event right? And I presume that means the
"production" trajectory has to have at least a bit of arc to it.

[Jochem Huhmann]

Jeff Findley <jeff.f...@nospam.ugs.com> writes:


> Computer simulations are a good thing (I write engineering software for
> a living). But, there really is no substitute for testing the real
> thing in the real world. Real world testing often reveals issues that
> the computer simulations missed. As a software developer, I'd like to
> note that even if the computer software is "perfect", if the input isn't
> perfect, the simulation will suffer from the dreaded "garbage in,
> garbage out" principle.
>
> This is precisely why SpaceX will have the first stage on the next
> flight start testing how to land the thing. Doing this over the ocean
> seems like a great idea, since on an expendable you've got to clear the
> area anyway. It will cost them very little to perform these sorts of
> tests.

I totally agree with you here. Simulations at least can give you a good
assessment if what you want to do is possible at all. To make it
actually work you need testing. Since SpaceX obviously is trying to make
it work this means that the basic flight profile etc. seem to work out
in simulations. And since they don't talk about it we can just
speculate. Which is totally fine and interesting I would say.

My speculation is that the first stage will have a steep (mainly
vertical) trajectory so that the stage isn't too far downrange and high
enough to be able to cancel out the horizontal component and fly back to
the launch site before it hits the denser atmosphere. The actual reentry
(if you can call it that) will happen already very near the landing
site. Because once you're in the dense atmosphere this thing *will* fly
with the engine forward. Which means that you can brake and steer it,
but not fly it very far or fast anymore.

[Greg (Strider) Moore]

> "Jochem Huhmann" wrote in message news:m2obcwv...@revier.com...
>
>"Greg (Strider) Moore" <moo...@ignorethisgreenms.com> writes:
>
>>>She's right though. "Space" may begin at 100 km, but hopping up and down
>>> isn't "going to space" in any meaningful way. It's more
>>> commercialization of high-end joyrides than commercialization of
>>> space.
>>
>> It's space. It's commercial. So what if it's only joy-rides?
>>
>> The folks paying know what they're buying and seem quite happy with that.
>
>Nothing wrong with that, but lumping it in with spaceflight (which is
>much harder to do and a totally different thing) just because it touches
>space for a moment isn't very wise.

So why do you keep insisting on doing that if you disagree with it?

Note, I didn't lump it in with "spaceflight". I lumped it in with the
commercialization of space.


>
>If those people having payed a deposit suddenly don't want to fly and
>the thing tanks, are you going to say "It has been proven that space
>tourism isn't viable"?
>

Why the hell would I do that?

>I mean, I would pay lots for being a week in orbit but I sure as
>wouldn't pay $200k for such a joyride.
>

Well, no one really is. Many are paying that much to be "among the first"
and they're paying for the "fun" of going through training and feeling like
an astronaut for a week.

They're paying for an "experience" that includes a space-hop.

If they can afford it, great. A little out of my price range.


>
> Jochem
>

--
Greg D. Moore http://greenmountainsoftware.wordpress.com/
CEO QuiCR: Quick, Crowdsourced Responses. http://www.quicr.net

[jacob navia]

Le 30/04/13 00:15, Greg (Strider) Moore a �crit :

> http://www.nytimes.com/2013/04/30/science/space/virgin-galactics-spaceshiptwo-inches-closer-to-space.html?_r=0
>
>
> Slowly but surely we're getting to more commercialization of space.

So, the U.S. manned space program that flew a man to the moon (around
300 000 Kms) is being replaced by this stunt that can fly some
plutocrats to 100 Km for a sky-high price.

And everybody agrees that this is the best that could happen, now that
we got rid of NASA and its huge burocracy. Private enterprise! That's
the new thing!

[Greg (Strider) Moore]

"jacob navia" wrote in message news:kmda6v$7ps$1...@speranza.aioe.org...

>
>Le 30/04/13 00:15, Greg (Strider) Moore a �crit :
>> http://www.nytimes.com/2013/04/30/science/space/virgin-galactics-spaceshiptwo-inches-closer-to-space.html?_r=0
>>
>>
>> Slowly but surely we're getting to more commercialization of space.
>
>So, the U.S. manned space program that flew a man to the moon (around 300
>000 Kms) is being replaced by this stunt that can fly some
>plutocrats to 100 Km for a sky-high price.
>

Ayup. I predict in the first operational year more plutocrats will fly to
100km than went to the Moon, for 1/100th the price.

Baby steps.

>And everybody agrees that this is the best that could happen, now that
>we got rid of NASA and its huge burocracy. Private enterprise! That's
>the new thing!
>

How long was it after the first European discovered America and before
permanent colonies were setup?

Baby steps.

[bob haller]

they have sold 570 seats so far at $200,000 each .......

[jacob navia]

Le 08/05/13 13:30, Greg (Strider) Moore a �crit :

> "jacob navia" wrote in message news:kmda6v$7ps$1...@speranza.aioe.org...
>>

> How long was it after the first European discovered America and before
> permanent colonies were setup?

After the discovery by Colon (1492) Hern�n Cort�s arrived to Mexico in
1517.

Only 25 years, what is much less than the gap between Neil Amstrong
(1969) and today (43 years)

And the U.S. is not even *planning* to return.