top ten reasons there'll be faster progress

Joe Strout wrote:

No, that's not the case. Improving suborbital flight could mean many
things, I suppose, including reducing cost and improving reliability (I
might argue, for example, that SS1 is already well beyond the X-15 in
terms of reliability, though there's certainly room for lively debate on
that one).

But when you consider what direction the market forces are likely to
push, it's almost certainly going to be for higher, faster, longer
microgravity flight profiles. And continued revision and improvement in
this direction leads directly (yet incrementally) to orbital flight. So
you can't "improve suborbital flight all you want" and be no further
than the X-15; at some point you've improved it well past the X-15 and
into the orbital realm.

Indeed, both the economics and the physics dictate this. The longer
the suborbital flight the longer the purchased experience, with very
little add-on cost for the provider; hence the greater the profit to
the provider because a longer experience can be sold for more than a
shorter one. But physically speaking, a suborbital flight can only be
lengthened so far until it is an orbital flight. And an orbital flight
can be sustained indefinitely.

This applies to passenger transportation at least as much as to
tourism. A short suborbital flight offers few if any advantages over
ordinary air travel; a long one can get passengers to their destination
faster than any atmospheric airliner. And as we construct more manned
facilities in space, a sufficiently fast flight can put passengers in
orbit. (There is already a potential market involved handling
personnel and cargo transfers with the ISS).

There's the direct incremental improvement noted above. In addition,
many of the problems faced by suborbital craft are similar or the same
as those faced by orbital craft: the need for a reaction control system,
for example. Also cabin pressurization, non-airbreathing engines, all
components being rated for use in space, TPS (though admittedly to a
much lesser degree, and somewhat depending on other craft parameters),
and so on. A high flight rate, with accompanying rapid progress on
these fronts, certainly makes the overall problem of building an orbiter
easier, don't you agree?

Almost all the technical problems are identical. The main difference
is the duration of the required life support systems.

My problem with this is that there has been lots of money to be made for
less costly launch capability for some time.

Yes, the market has been there, but it hasn't been recognized until
recently. Moreover, the very idea that private companies could run
their own space program was met with nothing but giggles until about 5
years ago. The giggle factor is gone, making investment more possible;
and then of course we have the modern angels (Munsk, Bezos, etc.)
serious about doing it themselves.

One cultural change has been that the generation of bright kids who
grew up reading science fiction and watching the early space program in
the 1950's and 1960's now has some members who are old enough to
occupy top positions in large corporations. This was something I long
expected, and am happy to have lived long enough to see realized.

Slots for comm satellites,
weather satellites, mapping satellites, and on and on.

Tosh. These are a small market, and don't demand a high flight rate,
and have been supplied mainly by government launchers. Sure, they would
have been better off with cheaper launches -- and this is an angle
SpaceX is taking even today -- but the existing expensive launches were
good enough; these customers were not price-sensitive, and the volume
was too low to drive much in the way of real competition.

Human passengers, in contrast, will (after the early adopters) be rather
price-sensitive, and will be flying in high enough volume to drive
competition. This is a completely different sort of market. Groping
for analogy here, consider the ocean liner industry as compared to the
auto industry. The latter advances much faster.

Very good point.

I'll add to this that, once one has private orbital flight, one can
have private space stations and there is then a market for satellite
_maintenance_. Once there is infrastructure in orbit, it becomes
cheaper to repair malfunctioning satellites than to launch
replacements.

Sincerely Yours,
Jordan

On Wed, 28 Jun 2006 05:29:46 GMT, in a place far, far away,
(Derek Lyons) made the phosphor on my monitor glow
in such a way as to indicate that:

Jim Kingdon wrote:

Moreover, substantial suborbital operations will create the beginnings of
a supplier base for commercially-priced (as opposed to government-priced)
engines, guidance, materials, safety systems, etc.

It'll be interesting to see how far that effect goes - as most
potential operators seem to be mostly 'rolling their own'

Even at this early stage, there is some evidence that operators are
not just rolling their own. The most obvious example is Virgin:

Operator = Virgin Galactic
Vehicle = Scaled Composites
Engine = SpaceDev

No. The vehicles comes from The SpaceShip Company - owned by...
Virgin (and Scaled) and with an exclusivity clause that prevents the
ships from being sold to anyone but Virgin.

I don't know if that's true or not, but Virgin has expressed
willingness to purchase vehicles from other providers.

"steve" wrote:

:
:One thing which has not yet been mentioned in this thread is the
:concept of the space rotovator.
:
:This is a permanently orbiting rotating cable which a suborbital space
:craft can transit to.
:
:As the cable probably something of 1000km long is rotating in the
pposite direction to the orbit it can be arranged so that the Delta V
:to reach this is very low.

For some relatively large value of "very low"

:http://www.liftport.com/forums/showthread.php?t=437

But this thing involves the development of several special purpose
vehicles, development of materials we don't have to build the cable
out of, hypersonic rendezvous with the rotating cable, and lofting
hundreds of tons of hardware into orbit and keeping it there.

Long before there's enough of a market to warrant this sort of sunk
development there would be enough of a market to keep a heavy lift
'dumb booster' busy. There doesn't seem to be enough lift work to
warrant even the development of that in the near term, although I
think it would be useful once we had it just because of the doors the
capability would open up with regard to things we could then think
about doing.

It seems to me that rotovators, space elevators, etc, are at least
half a century out at a minimum.

--
"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

In article ,
Derek Lyons wrote:
Moreover, substantial suborbital operations will create the beginnings of
a supplier base for commercially-priced (as opposed to government-priced)
engines, guidance, materials, safety systems, etc...

It'll be interesting to see how far that effect goes - as most
potential operators seem to be mostly 'rolling their own'.

Most of them would *like* to be able to buy more of the parts and
subassemblies off the shelf, but are finding it difficult to do so.
But even with the industry in its embryonic state, we're seeing some
subcontracting, e.g. Frontier Astronautics doing attitude control for
Masten Space's rocket. If it becomes a competitive commercial business,
there'll be more of that.

And don't forget the "intangible subassemblies" (which I did forget...),
like insurance. One non-trivial side effect of the Rocket Racing League,
assuming it reaches takeoff :-), is that there'll soon be a substantial
number of independent owner-operators shopping for third-party-liability
insurance for rocket vehicles -- something that is currently hard to find
and can be a significant problem for startups.

For the
long term health of the industry, we need to follow the same path
virtually every other transport industry has followed - airframe
manufacturers need to be seperate from operators.

I was thinking more of subsystems than of entire airframes; the subsystem
market has the potential to be viable before the airframe market is. But
you're right in the longer term -- builder-operators should be special
cases, not the norm.

Some of the current airframe builders are willing to sell rather than
operate, and at least one would *prefer* to sell rather than operate.
--
spsystems.net is temporarily off the air; | Henry Spencer
mail to henry at zoo.utoronto.ca instead. |

In article . com,
Jordan wrote:
even better, there are actual commercial applications of suborbital
technology -- one being thrill-flights, but another one being very
rapid intercontinental air travel...

Unfortunately, that last depends on spaceships being approved for air
transport service... from ordinary airports. In 1945, that was not a big
stretch. But the bar has been raised greatly in the last half-century:
modern airliners are expected to be much more reliable than their 1945
counterparts, the regulatory hurdles they have to jump have gotten much
higher, and issues like airport noise are now quite important.

Thrill flights have the large advantage that you can -- in fact, with the
current state of the art, you must -- bill them as high-risk adventures,
on a par with climbing Everest, which are quite likely to kill some of the
participants. (Something like 20% of Everest climbers don't come back.)
Air transport is a very different matter.

Between reliability issues, noise issues, and the fact that the regulatory
authorities are nowhere near ready to certify a ballistic rocket vehicle
for routine air-transport service, you won't see intercontinental
passenger rockets until the third or fourth generation of commercial
spaceships. They aren't on the path to orbital vehicles; the thrill
flights will go orbital well before that.

You also have at least five national space agencies launching orbital
payloads...

That's been true for many years; this is not some radical new development.
In particular, China launched its first satellite in 1970, and its first
recoverable satellite (the key technology needed for manned spaceflight)
in 1975.

and at least two interested in constructing manned Moonbases.

Careful here. There's a big difference between being interested in doing
it, and being funded to do it. At least two national space agencies have
been *interested* in manned Mars expeditions for 40+ years, but neither
of them has actually made any great progress toward doing it.

We're seeing a Second Moonrace starting right before our eyes.

My, this silly idea just won't die. No, we aren't. The reason there was
a race the first time was that in the wake of Sputnik, space was perceived
as a major arena of superpower competition -- an important measure of
technical capability and national will, something that could seriously
influence which side of the Cold War an undecided nation might take. That
driving *political* importance simply isn't there today. There is no Cold
War, and the Chinese aren't likely to start one, because they saw what
happened to the last people who did that.

Space is not important for its own sake, and never has been. (The USSR
was ahead of the US in space for most of the 1980s; nobody got excited.)
--
spsystems.net is temporarily off the air; | Henry Spencer
mail to henry at zoo.utoronto.ca instead. |

"Jordan" wrote:

Wayne Throop wrote:

My problelm with this one is that you can revise and improve suborbital
flight all you want, and you're still no farther along than the X15 was,
in terms of basic capability. Is there some reason to think this will
spill over to orbtial capability?

Well, yes. Suborbital and orbital technology are just different
aspects of the same technology, which is launch technology in general.

Well, from the same point of view a Piper Cub and a F-15 are different
aspects of the same 'technology'. (Misusing the word technology as is
the fashion nowadays.)

D.
--
Touch-twice life. Eat. Drink. Laugh.

-Resolved: To be more temperate in my postings.
Oct 5th, 2004 JDL

In article ,
Jim Kingdon wrote:

I expect this kind of supplier base (I guess we call it "vertical
non-integration") to be more prominent if/when/as the industry starts
to grow. Having the engine company separate from the vehicle company
is more likely to produce benefits if more than one vehicle company is
buying engines from them. And it might take a while for that
situation to develop.

If you're right, this would be a good time to by XCOR stock (if such
were available). They produce first-rate, top-notch liquid propellant
engines, and I would certainly expect them to be the premier supplier of
such when spacecraft builders start coming out of the woodwork.

Best,
- Joe

In article ,
Joe Strout wrote:
...You don't gradually improve suborbital vehicles to make orbital
ones -- it's a substantial jump up in technology.

But what about the point that, in a competitive market, those who offer
a longer microgravity time are offering a better product?

I don't see that being a big enough advantage to fund a lot of incremental
improvement, after obvious inadequacies of the pioneering vehicles are
addressed. Going from 5 minutes to 10, yes. But going from 25 to 30? I
think suborbital will hit a plateau where the market forces pushing for
incrementally-higher performance are relatively weak, and another big jump
is needed to attract significant investment. (I could be wrong.)

...I suppose that, in principle, you could instead
just throw yourself higher straight up, without accelerating
horizontally...

Indeed, there are people who will tell you that it's preferable, some of
them friends of mine. :-) I'm not sure I believe them, but it does avoid
some hassles like needing two separate flight bases.

... (1) it would mean a much hotter reentry, and (2) you're not taking
advantage of the curvature of the Earth to increase your hang time.

You don't get a lot of benefit from the curvature until you're very close
to orbital. (Similarly, you can't go, say, trans-Pacific on a ballistic
trajectory without getting pretty close to orbital.) The reentry is the
big snag with going vertical.
--
spsystems.net is temporarily off the air; | Henry Spencer
mail to henry at zoo.utoronto.ca instead. |

In article .com,
"steve" wrote:

One thing which has not yet been mentioned in this thread is the
concept of the space rotovator.

I think this thread is more about incremental development of existing
approaches -- i.e., rocket launch -- rather than more radical ideas,
like rotovators and space elevators.

However, I agree that the rotovator is a very interesting idea, and
probably worth pursuing. Most likely, if it has any merit, some company
or another will pursue it -- they might be able to use their same (or
very similar) suborbital vehicle, but suddenly offer customers an
orbital experience for not a lot more money. That will be a HUGE
incentive, pretty much guaranteeing that it will at least be considered.
(A good example of why a competitive commercial market will develop much
faster than government space programs, even if this particular idea
turns out to be impractical.)

Best,
- Joe

In article ,
Fred J. McCall wrote:

[Re. rotovators]

But this thing involves the development of several special purpose
vehicles, development of materials we don't have to build the cable
out of, hypersonic rendezvous with the rotating cable, and lofting
hundreds of tons of hardware into orbit and keeping it there.

Fred, you haven't done your research, or you're purposely being
negative. Rotovators don't require any new materials, nor do they
require more hardware than can be launched by, say, a Zenit. Nor is
that hardware any harder to keep in orbit than any other satellite.

(I do agree that the rendezvous may be a sticking point, though.)

It seems to me that rotovators, space elevators, etc, are at least
half a century out at a minimum.

I don't think you should lump those two together -- they're in
completely different classes, both in operational characteristics and in
technology requirements.

Best,
- Joe