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Subject: SPACE Digest V13 #326

SPACE Digest                                     Volume 13 : Issue 326

Today's Topics:
         NASA Headline News for 03/26/91 (Forwarded)
                Re: "Follies"

Administrivia:

    Submissions to the SPACE Digest/sci.space should be mailed to
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Date: 27 Mar 91 01:31:38 GMT
From: [e-mail]  (Peter E. Yee)
Subject: NASA Headline News for 03/26/91 (Forwarded)


             Headline News
Internal Communications Branch (P-2) NASA Headquarters

  Tuesday, March 26, 1991    Audio Service: 202 / 755-1788

This is NASA Headline News for Tuesday, March 26, 1991

The Flight Readiness Review for the STS-37 mission is underway at
the Kennedy Space Center.  The review will conclude tomorrow with
an announcement of a launch date.

Atlantis' main engines are undergoing their flight readiness
test.  This test is used to calibrate engine sensors and also cycles the
valves on the three main engines.  The Gamma Ray Observatory
spacecraft end-to-end test was completed successfully last night.
There are no open items with the GRO payload.  Payload bay
doors on Atlantis are expected to be closed tomorrow.  Aft closeouts on
the orbiter are presently underway as activity on launch pad 39-B
continues toward a launch in early April.

Discovery is hoisted and in the process of being mated to its STS-
39 external tank in the Vehicle Assembly Building.  It was rolled over
last night.

In the Orbiter Processing Facility, technicians continue to hook up all
of the  electrical connections between the orbiter and the Spacelab Life
Sciences habitable module.  The interface verification test between the
orbiter and the Spacelab module begins tomorrow and is expected to
continue all day.

                   * * * * * * * * * * * * * * * *

Office of Space Flight Associate Administrator Bill Lenoir and KSC
Center Director Forrest McCartney paused briefly this morning during
the FRR to join Deputy Associate Administrator for Space Station,
Dick Kohrs, for the groundbreaking of KSC's new Space Station
Processing Facility.  The SSPF will be a new KSC facility occupied
by about 1,000 NASA and contractor employees.  The three-story SSPF
will include communications and electrical control areas, laboratories,
logistics staging areas, operational control rooms, office areas and a
cafeteria.  The facility will have over 63,000 square feet of
dedicated payload processing space, including a high bay and
intermediate bay.  A 5,000-square-foot airlock will be adjacent to the
primary processing area.  Both the airlock and processing area will be
clean rooms rated at 100,000 parts-per-million.  It will be the largest
new construction project undertaken at Kennedy Space Center
since Apollo.  Anticipated cost of the building is just over $56 million.

                   * * * * * * * * * * * * * * * *

The National Science Teacher's Association annual convention
gets underway tomorrow in Houston.  NASA is providing several
exhibits and will provide tours of the Johnson Space Center for teacher
groups during the three-day convention.



Here's the broadcast schedule for Public Affairs events on NASA Select
TV.  All times are Eastern.  NASA Select TV is carried on GE Satcom
F2R, transponder 13, C-Band, 72 degrees W Long., Audio 6.8,
Frequency 3960 MHz.

Tuesday, 3/26/91

    12:00 pm    Starfinder:  Tapping the Sun's Power.

    12:15 pm    Replay of American Astronautical Society Goddard
            Symposium, Welcoming Remarks and Keynote Address
            (recorded on 3/14/91).

     1:00 pm    Sail On Voyager program.

     6:00 pm    Repeat of afternoon programming.


All events and times may change without notice.  This report is filed
daily, Monday through Friday, by 12:00 pm, Eastern.  It is a service of
NASA Headquarters Office of Public Affairs.  Contact:  CREDMOND
on NASAmail or at 202/453-8425.

------------------------------

Date: 26 Mar 91 07:15:53 GMT
From: zephyr.ens.tek.com!tektronix!sequent!crg5![e-mail]  (Nick Szabo)
Subject: Re: "Follies"

In article <[e-mail]> [e-mail] (John Roberts) writes:
>>It is up to those requesting $billions for rocket programs to prove
>>they _can_ lower launch costs.  It is not up to me, requesting no money, to
>                                                     -------------------
>>prove they can't.
>
>Not quite. If you were simply *not requesting money*, I would agree. But
>you are actively *requesting 'no money'*,

I am requesting that government chemical rocket proponents provide positive
evidence that such rockets _can_ reduce costs as claimed.  So far, no such
evidence has been presented in this forum.   (Answering negative evidence is
not the same as presenting positive evidence).  Yes, they do need to present
evidence, and have it withstand scrutiny, before they should be funded --
just like any other engineering project.

Every piece of positive evidence I've seen outside of this forum has holes
a mile wide (including Max Hunter and Gordon Woodcock -- yes, I _have_ read
a bunch of the literature -- what I have read and what I have seen in this
discussion is what has convinced me that further reading of it is a waste
of time, unless there are short references that specifically address the
point we are discussing).


>>On the first point, divide the cost of a hypothetical Shuttle/OTV
>>trip to L-5 ($40 million/person) with round trip first-class from
>>Tokyo to New York ($2,000/person) to get 4 orders of magnitude.
>
>Remember
>that many colonists were willing to obtain passage by selling themselves
>into indenture - basically limited-term slavery, the usual term being seven
>years.

Not middle-class colonists at middle-class wages.


>Playing around
>with the numbers, if we accept the premise that some people will be willing
>to colonize if it costs the equivalent of seven years' labor just to get
>set up, and placing a more modern US middle-class labor valuation at up
>to $100000/year (salary x multiplier, where multiplier is in the neighborhood
>of 3-5),

I don't know where you get a "multiplier".  Per capita income in the U.S.
is c. $19,000 (don't forget we need to transport the whole family), or
around $12,000 after taxes.  A good (way above average) savings
rate would be 10%, or $1,200/year after taxes, food, shelter and health
care, or $8,400 over those 7 years, per person.  At $2,000 per seat,
this leaves $6,400 per person to buy a home in space.   If we assume
that a space home cost only 1/4 of an Earth house (due to the greater
availability of matter and energy, combined with the presence of a
mature space mining and manufacturing industry) then $2,000 is the highest
affordable ticket price for the average family in a developed counntry.
Currently, housing in space costs 300,000 times as much as on Earth
(assuming Fred will last as long as a house), but we are not making
use of the material and energy of space to build it.

OK, here is a poll -- how many reading this (anonymity garunteed) have
enough saved up _now_ (including unmortgaged portion of house, car value,
savings, etc.) to pay passage and buy housing for 2 people at these
prices ($16,800 total).  Would you pay this to resettle in space?
If you have a family, would they agree?

I suspect the number of people who want and can afford space colonization,
even in this pro-space forum of over 10,000 mostly above-average-income
professionals and temporarily poorer students, will be surprisingly small,
under these conditions (4 orders of magnitude drop in launch costs).  At
4 orders of magnitude (and even more important, a mature space mining
and manufacturing industry), we just start to reach the point where a
significant minority can afford to live permanently in space.


>(further assuming
>the eventual utilization of local resources, of course) with only two
>orders of magnitude drop in launch costs.

Sure, if you fudge two orders of magnitude in your numbers.  :-)

There is a scenario where we could get down to 3 orders of
magnitude -- if space exporting industries grossed so much revenue, that
the average space wage was far higher than the contemporary developed country
wage.  Assuming space housing costs are still 1/4 Earth housing costs,
each person needs $86,400 for a 3 order of magnitude drop in launch
costs.  This translates to $432,000 for a family of five.   Tickets could
be bought against future wages.

Currently an astronaut in space costs $100 million per man*year, though
the economy of the services provided is debatable, and they are actually
payed only c. $60,000/year.  Given the nature of materials and energy in
space, and the initial labor shortage, wages high enough to pay off a
$432,000 loan in a few years are not inconceivable for a highly skilled
worker, but it again requires a mature, highly automated space industry
grossing tens to hundreds of billions of dollars per year in exports.
If space provides even more wealth to Earth for a small amount of
on-site labor and high profit margins, even higher wage rates could
envisioned.

Even so, chemical rocket costs cannot be dropped 3 or even 2 orders of
magnitude, as I have demonstrated.

The most likely scenario for a 3-4 order of magnitude drop is a
laser or airplane launch into a suborbital trajectory above
the atmosphere ($1,000/person), combined with a large, space-manufactured
tether system to provide most of the delta-V to L-5 or other solar system
destinations (also $1,000/person, assuming mature space mining and
manufacturing industries).


>Many people do consider two
>orders of magnitude to be within the realm of possibility for chemical
>rockets.

Again, there is no valid evidence for this, merely some claims
I have read, with holes a mile wide.  The economic evidence (price
curves, and 2 different comparisons to other chemical powered transportation
systems) indicates that rocket costs won't fall any faster than the cost
of cars or airplanes.  Better technologies are needed.


>And chemical rockets have the ability to perform functions some of
>the other options can't - such as getting live humans into space.

Lasers or airplanes combined with tethers would also serve to launch
passengers, far more cheaply.


>The more I look at your unbending insistence on 4 orders of magnitude launch
>cost drop,

"Unbending"?  Please, cut the rhetoric.  I have arrived at the same
rough figure two different ways, and have proposed a space-industry-wealth
scenario where only 3 orders of magnitude is needed.


>have effectively been urging the abandonment
>of work aiming toward systems that could drop costs by "only" a factor of
>10 or 100. I'm sorry, but I think there would be a *lot* of benefit to
>dropping costs by that amount.

I am certainly not discouraging work to drop costs in such a large fashion.
EML, gas gun, laser launch, tethers, etc. (notice that I am not promoting
a pet project, but advanced technologies in general) can (and will, if we
drop our chemical obsession) drop launch costs a factor of 10-100 far sooner
than chemical rockets will.  Sandia makes the not too unrealistic claim
of $200/lb. for a $2 billion investment for EML, within five years.
This is 1/15th the cost of the Shuttle, and 1/2 of its development time
-- why not try it?  If we were not so obsessed with chemical rockets, we
would.


>>On the second point, several methods will derive a similar result.
>>Back-of-the-envelope numbers, within +/- 50% will give sufficient
>>precision to demonstrate the point.
>
>
>>* Take the curve of rocket costs/lb. ($1991).  Project it into the future.
>>  1960 = $12,000/lb., 1970 = $8,000/lb., 1980 = $6,000/lb.,
>>  1990 = $5,000/lb, 2000 = $4,250/lb., ....2030=$3,000/lb.,...
>>  2090 = $2,000/lb., ....
>
>Similarly, for linear launchers and laser launchers -
>[infinity, infinity, etc. etc.]

  ;-)

Haven't even been prototyped yet (and BTW infinity cannot be plotted,
which makes it kind of hard to visulize your curve -- maybe the cost
is decreasing by an infinite factor in each inifinitely small period
of time?  :-).  Chemical rockets are mature technology.  Liquid rockets
are much older than microchips, and also older than transistors or jet
airplane engines.   Solid rockets predate guns by several centuries.  EML
and laser launch and space tethers are very new, while gas guns are
substantially new (Dr. Hertzberger's preferred term is "hyperaccelerator",
because it adds several new principles to gun operation).  Rockets are
at the diminishing returns of their curve; the newer technologies have not
yet started down that path.


>...I think extrapolating curves from the past is generally
>a very poor way to predict future costs, given continual advances in
>technology and shifts in design goals and investment patterns.

Ah, that's the phrase I am looking for -- advances in technology.
Surely we can get off the launch cost curve, but if we want to
dramatically change the curve, we need to dramaticallly change the
technology.


>My reply would be that nobody has yet worked really hard or invested a lot
>of money in greatly reducing per-pound chemical rocket launch costs either.

Rocket engineers have been obsessed with launch cost/lb. since the early
70's, so this is most assuredly false, protestations to the contrary.


>Quite a few people have pointed this out to you, and you have ignored it.
>(The Shuttle started out largely as such an effort, but was subverted by its
>DoD sponsors into stressing performance over price, which as we know painfully
>well is no way to minimize price.)

I ignored it, because it is so obviously false.  You can't be around a
rocket engineer or space fan for very long without hearing cost/lb., and
getting into this vs. that rocket cost/lb. discussions like the ones that
dominate sci.space.  The DoD did not significantly impact the Shuttle price
with its minor design requests, since NASA was still quoting the ridiculous
$100/lb. after the DoD design changes.  The technology is inherently expensive.


>There *is* increased interest now in
>reducing per-pound chemical rocket launch costs -

There has been obsessive interest in it since the early 70's, with little
impact.


> for instance the expanded
>Delta and Titan designs described by Allen Sherzer (with hope for up to 2-3X
>drop in cost/pound, and availability in perhaps only a few years),

Estimates are based on fact not "hope".


>and ALS
>or the new technology launcher system (with development expected to take about
>a decade, and perhaps as much as 10X reduction in launch costs).

A totally irresponsible estimate, like the Shuttle estimate.  Let's see
the positive evidence to back up this wild claim.


>>[two indepedendent comparisons of rockets with other transportation]
>>[systems show that rockets costs are about where they should be]

>These last two arguments are an attempt to eliminate technical details,

Not at all.  No one has introduced technical details that provide positive
evidence for lower chem rocket launch costs, because such technical evidence
does not exist.  _I_ am introducing perfectly valid economic comparisons
with energetically similar transportation systems. I could introduce more
detailed technical evidence, such as the excellent refutation of the
cube/square fallacy recently posted, but the economic analysis is more
valid, since we are talking about practical engineering dollars, not
abstract physics.


>I just don't see a benefit from deliberately avoiding the technical
>details in order to obtain some high level of abstraction,

Fine, please introduce some technical details that are more relevant.
For example, we might want to talk about the complexity involved in
gyroscopes and the precise gimballing of high-power thrusters, high-power
cryogenic pumps, tracking, the handling of large amounts of flammable
oxidizers and liquid oxygen, the handling of large ductile structures,
etc.  etc. You don't want to talk about that, because then the necessary
complexity of rockets, and the reason they aren't an exception to the
vehicle/fuel cost and fuel/payload mass ratio curves, would become readily
apparent.


>For the idea of vehicle cost being a function of the cost of a tank of fuel,
>if there's any validity to it at all, then it must be a function of underlying
>factors, such as design constraints, intended use, and the physical properties
>of the medium through which it travels.

The medium, intended use, and design constraints impact both the fuel
requirements and constructions costs, which are then traded off to provide
the typical 10^3 factor for many different kinds of internal-chem-powered
vehicles, as I demonstrated.


>It would be foolish to ignore these
>details, for if you just assume it to be a universal principle, then you must
>fit in all vehicles, such as boats, horses, etc.

Boats do lie on the curve, despite the rather congenial method of floating
on water.  As stated above, the congenial medium and constraints simply make
both fuel and construction costs cheaper per pound than a land-based vehicle.
The curve simply represents the general tradeoffs involved in building a
vehicle around the limited energies of on-board chemical reactions.  I'm
not making this up; work out the various examples for yourself.

As a half-serious aside, horses aren't powered by fossil fuels, but
interestingly enough the cost of an average horse ($4,000) is about 10^3
times the cost of a bale of hay.


>Looking at the details, it
>could well be that the apparent identical multiplier for cars and airplanes
>is just a coincidence, or that a comparable multiplier for advanced chemical
>rockets should be very different.

Boats, cars, airplanes, rockets, (and maybe even horses :-), all with the
same factor of 10^3, all a coincidence?  More like, a fundamental reflection
of the efficiencies of on-board chemical reactions.


>In any event, trying to apply such a number
>to a future system is of very limited value, especially if you try to use it
>as a guide for design.

It is infinetely better than pulling a wishful number out of the air, or
basing numbers on abstract physics that ignore 99% of the design issues.


>Imagine using this formula as an explanation for why
>cars that use premium gasoline cost more than cars that use regular gas,

In fact, premium tends to be used more often by sports cars, which are
more expensive.  This fits the 10^3 law very well.


>or designing a new car with a gas tank only half normal size, on the grounds
>that this should cut total vehicle cost by around 50%.

People expect to drive a certain range in their cars, and will pay far
much less for those they must continually drive into the gas station.
Interestingly enough, more fuel-efficient cars do have somewhat smaller
tanks and do in fact cost less, by about the same factor as their increase
in efficiency, again providing another data point for the 10^3 law.
The ratio is slightly higher than 10^3 for some non-transportation
purposes, such as race cars and ICBM's; the law is only intended to
apply to practical, commercial-style transportation systems.


--
Nick Szabo            [e-mail]
"If you want oil, drill lots of wells" -- J. Paul Getty
The above opinions are my own and not related to those of any
organization I may be affiliated with.

------------------------------

End of SPACE Digest V13 #326
*******************