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Subject: SPACE Digest V12 #514

SPACE Digest                                     Volume 12 : Issue 514

Today's Topics:
       Re: You Can't Expect a Space Station to be Cheap
                   Re: X-15

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Date: Tue, 30 Oct 90 22:19:52 -0500
From: "Allen W. Sherzer" <[e-mail]>
Subject: Re: You Can't Expect a Space Station to be Cheap
Newsgroups: sci.space
Cc:

In article <[e-mail]> Charles Radley writes:
>+ Boeing just sold United a bunch of planes which don't exist yet. Sold
>+ them for a fixed price before beginning the design in detail.

>Boeing has a long track record of building highly successful
>aircraft.   LLNL does not have any track record at all in large
>space systems.

First of all, that is irrelevant. Large engineering programs
CAN be done on time and on cost. Second of all, the LLNL contractors
on this DO have a good track record in large aerospace systems.

>+ Besides, what do we have to loose? If it doesn't work, I'll
>+ join you to be the first to call for killing it. If it does
>+ work, we will have a space station in three years

>At what point do you decide it does not work.

That is a fair question. Let's see... Freedom was to be done in six
years and cost 8 billion. Instead it will take 20 years and over
40 billion which is 2.5 times as long and five times the cost (these are
very conservative numbers, my sources on Freedom say it will be much worse).
I propose we do better and allow LLNL to slip by a factor of 2 in
both time and cost.

If LLNL doesn't have an Earth Station in orbit four years after start
costing under $4 billion I will call for it to be killed. How's that?

>So if it is 3 years late and does not work, six years
>have been lost with nothing to show for it. ^^^^^^^^^^

Interesting choice of numbers. Freedom was to be ready in about six years
with the start of operations next year. We have already spent six years
with nothing to show for it (not counting the $8 billion in briefing
slides that is).

>On the other hand,
>if congress stops messing with the budget, I have little doubt
>that Freedom could achieve MTC and then PMC more or less on time.

That is not the problem. A 10% cut is enough to send all of Freedom
back to the drawing board. That is bad project management. Projects
I have managed have taken harder hits without tossing everything out.

Besides, sources on Freedom say that the budget cuts are the excuse
not the cause of the redesigns.

>+ and almost an order of magnitude reduction in launch
>+ costs for large payloads. All that is needed to demonstrate the
>+ concept is about 5% of one years spending on Freedom.

>Sounds cheap enough.  Let them get on with.    But not with my
>budget.

No problem. It won't come out of your budget.

>+ANY serious flaws in their approach.
>
>   Proposing untried NiH batteries which have no advantage over
>existing ones;

These batteries provide more power for less weight. This results
in cost savings which most people think is an advantage.

>proposing untried amorphous silicon cells with
>dubious qualification prospects and admitting conventional cells
>woulBd be just as good and less risky;

See above.

>presupposing a brand new
>ELV will be ready on time in three years and cost next to
>nothing; - all this I find hard to swallow.

Tell us what part is hard to swallow? Have you read up on them?
MDAC and Martin Marietta say it can be done. What do you know
that they don't? You spoke above about Boeing and how they could
estimate cost because they had a track record. Don't these companies
also have a track record?

It is hard to talk about this if you can't be more specific than 'hard to
swallow'.

But again, none of these are serious problems. If they work, we advance
the state of the art and save money. If they fail, their weight budgets
and schedules allow for it.

>  Another concern I have is with the inflatable structure.  What
>is its factor of safety on burst ?

The contractor for the inflatable structures is ILC Dover. They
have experience building similar sized structures for aerospace
applications. They also have built all NASA spacesuits since
Apollo. As such, they are well versed in the requirements for
this application. In their conceptual design they state:

   ILC believes that a modular inflatable space habitat is
   feasible within the current state of the art of softgoods
   materials and assembly techniques. [1]

And NASA says:

   Tests on full-scale models of representative concepts show
   that they [inflatables] are sound structurally, have satisfactory
   deployment characteristics, and in most instances possess remarkable
   packaging ratios. With attention to design and fabrication
   details, they can be made leak tight and as resistant to micro-
   meteroroid penetrations as comparable metallic structures. [2]

>Since it is not possible to
>do fracture mechanics on non-metallic structures, there are only
>two ways to qualify it to MIL-STD-1522, or the NASA NHB-8071.1
>which are basically the same....

A NASA contractor and NASA both say it will work. I think it is
safe to say that both are up on the relevant standards and laws.

> >+Why? If Freedom used expendables instead of insisting on using
> >+ the Shuttle their costs would also drop. At $500 to $900 a
>> pop  those assembly costs add up fast. Why is that apples and
>>+oranges?
>The assembly flights require manned presence.    Will the LLNL
>HLV be manned ?  If so, their cost estimates are *@*#&*

Deployment does not need to be manned. There is no reason that the
station cannot go up in the HLV with the crew following in the
Shuttle or on a (safer and cheaper) Delta.

Crew launch could happen days, weeks, or months after launch
of the station.

>+ NASA is claiming ten Shuttle flights a year for assembly. This
>+ flies in the face of the past ten years operational experience
>+ with the Shuttle, ignores problems with an ageing fleet, and
>+ discounts problems with the fleet being grounded. The last is
>+ an important factor since the Shuttle has been grounded for
>+about a third of it's operational life. Because of this, Freedom
>+ could well end up being deployed in Australia next to Skylab.
>
>True, but does not eliminate the HLV risk.    Compare the devil
>you know with the devil you do not.

You miss the point. If the HLV is not available they can launch
the Earth Station on a Titan. Freedom was deliberately designed
to use ONLY the Shuttle. The LLNL plan allows for failure but
Freedom does not.

>+ They [LLNL] assume launchers will be grounded in their schedules. They
>+ assume things won't work and plan for backup approaches when
>+they fail.
>
>Really ?  Then their development schedules are even more success
>oriented than I thought if they think they already have that
>covered.

It is only good engineering to have a backup for all the methods
and technology you plan to use. I always do.

The question is why does Freedom continue to insist on over optimistic
launch rates and ignore the 50% chance (according to OTA) that
the Shuttle will be grounded?

>+ If the HLV is gounded, they could use Titan, Delta, or even the
>+Shuttle.
>
>Sure, but then their cost projections go out the window, and you
>end up with a system costing the same as Freedom.

No because the alternatives they use are all much cheaper than
the Shuttle.

>Adapting launch packages to fit three or four different vehicles sends
>your cost sky high.

Not in this case. The HLV fairing and interfaces are all compatible
with Titan IV. In fact, they both use the same fairing and interfaces.
A worse case failure will double their transport costs which will
go from $500M to $1B. See what can be done when you have a fallback
plan?

>+ From where I sit it is NASA by failing to plan for Shuttle
>+ alternatives which is taking the high risk, low credibility
>+ approach.
>
>Funny, I come to the exact opposite conclusion with the same data.

Can you give us a little more detail? OTA says there is a 50% chance
the Shuttle will be grounded due to orbiter loss during deployment.
Current optimistic assumptions require ten years of Shuttle flights
for assembly. If almost anything goes wrong during that ten year
period Freedom will re-enter and burn up.

That means there is about a 50% chance that Freedom will never
be built. I consider a 50% chance of failure high risk.

>With one exception, I would like to see an ACRV added to
>the program to get some independence from the Shuttle.

How does that make them independant of the Shuttle?

>+No, the cost still needs to be amoritized. I just flew back from
>+Dallas in a new 767. I'm sure part of the cost of that aircraft
>+ was to pay for the design. Just because it exists doens't mean
>+ you don't need to pay development costs.
>
>No. The cost does not need to be amortized.   It is written off.

If you want to know how much it costs, you do.

>The money has been paid.   The Shuttle was not built on credit
>(unless defecit spending counts as credit),

Well, we do pay interest on the deficit. I think it counts as credit.

>+One bad effect of this is that it hurts the domestic launch
>+ industry.
>
>No, it does not.  NASA is prohibited by Executive Order from
>competing with the commercial ELV industry.

Ah but it does. It takes buisness away and costs the taxpayers
billions.

>+ It is cheaper to design for no eva and do eva if needed than to
>+ require eva.

>Not really.   Once you provide the airlocks, EVA suits, training
>and all, then take it all into orbit, whether you use it or not
>makes little difference to the final cost.

The Earth Station already has an airlock and facilities for EVA.
It will be needed to get to and from the microgravity facility.

As to training, I quote yoru previous statement: 'remember Skylab?'.
In an emergency the plans can be made in a short time. This will be made
even shorter since the design allows for it.

>+LLNL will pay for the 20 flights. The entire Great Exploration
>+program uses 20 HLV flights for the Earth Station, Gas Station,
>+ and Lunar Base. Three flights are for the bases and the rest
>+ are for fuel and resuply.
>
>I am very glad to hear they have a magic source of money.   What
>is it that makes them exempt from the congressional budgetary
>process ?

They aren't. They just do good project plans which adapt to the
existing conditions.

>All Moon/Mars funding has been deleted, so how come
>LLNL think they are going to get congress to change their minds ?

They already have. The House Senate Conference put back the DoE
IR&D money. Some of this money will go to the Great Exploration
for A detaild study. After that, there is good reason to expect
them to start in earnest. This probram has the support of the Space
Council (Quale recently told the head of LLNL that he wanted to see this
program move forward).

>+ The  HLV's mentioned do not require new moving parts or
>+modifications  to their engines.
>
>Do not misunderstand me, I kinda like the idea of an HLV, I
>simply believe the cost and schedule predictions are way too
>optimistic.

I would like to see a reason more detailed. What specific engineering
problems are there?

> >>Any of those guys coming to southern California any time soon?

> >+ Invite them down

> >Hah !  I value my job too much.

>+ That's an interesting remark. Why would inviting some speakers
>+ in get you fired?

>I work for a Freedom contractor.    LLNL represents the competition.

Now that is another interesting remark. I routinely visit and look at
the work of my competition. I want to know what they are up to and
if they have any good ideas.

Why are your bosses so afraid of evaluating the competition? BTW, NASA
and LLNL recently signed a MOU on this. Both agreed to exchange information
and ideas. So I think you can do it without getting fired. If you can't,
why would you want to stay in such a place?

    Allen

[1] Conceptual Design Study for Modular Inflatable Space Structures
    by ILC Dover Dec. 4, 1989

[2] Expandable Structures Technology for Manned Space Applications by
    C. I. Tynan, NASA Langley Research Center

--
+-------------------------------------------------------------------------+
| Allen W. Sherzer      |         What should man do but dare?            |
|   [e-mail]         |             - Sir Gawain                        |
+-------------------------------------------------------------------------+

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

Date: 30 Oct 90 20:06:23 GMT
From: world!ksr![e-mail]  (Chris Jones)
Subject: Re: X-15

In article <[e-mail]>, henry@zoo (Henry Spencer) writes:
>
>If you're thinking of the Dyna-Soar, which I believe was the X-25 (I can't
>remember what the X-20 was offhand), it probably would have worked... but
>remember that it was basically a glider, launched by a large Titan.  There
>is no obvious reason why it wouldn't have worked, but on the other hand
>there was nothing terribly remarkable about it either.

The Dyna-Soar was not called X-25.  It was the X-20 (or X-20A), see below:
(BTW, I believe the Dyna-Soar would have used a Titan III.)

From the Space Link BBS, file 7.4.7:

                  In manned spaceflight, for example, there were
essentially four approaches to putting man into space:

O the research airplane--the Air Force and NASA were already well into this
program, leading to the X-15;

O the ballistic vehicle--NASA's Project Mercury embodied this approach, with
Air Force launch vehicles and DoD support throughout;

O the boost-glider--the Air Force had inaugurated the Dyna-Soar project (later
renamed the X-20) in November 1957.  A manned glider would be boosted into
shallow Earth orbit, bounce in and out of the top of the atmosphere for part or
all of a revolution of the planet, and land like an airplane.  In May 1958 NACA
had agreed to help with the technical side of the project.  NASA continued that
support;

O the lifting body--a bathtub-like shape proposed by Alfred J. Eggers of Ames
Laboratory which, as a reentry shape, would be midway between an airplane
configuration and the ballistic shape, developing moderate lift during reentry
and landing like an airplane.  This approach would be deferred for a few years
before being explored by the Air Force and NASA.

From the Space Link BBS, file 7.4.8:

  Although ballistic reentry from space had become familiar by the 1960s, there
was a group of engineers who argued in favor of "lifting" reentry.  The idea
was to build a spacecraft with aerodynamic characteristics so that a crew could
fly back through the Earth's atmosphere and land at an airfield.  The X-20A
Dyna-Soar proposed by the Air Force was one such example.

  But the Dyna-Soar never flew, a victim of budget constraints and new
technology.  The NACA became involved in a smaller series of lifting-body
aircraft that helped pave the way for the Space Shuttle design.  At Ames, a
series of exploratory studies during the 1950s culminated in a design known as
the M2, a modified half-cone (it was flat on the top) and a rounded nose to
reduce heating.  NASA engineers at Edwards kept up with much of the theoretical
ideas percolating out of Ames, and Robert Reed became fascinated by the M2, by
now called the "Cadillac" for the two small fins emerging at the blunt tail.
He built a successful flying model, which led to authorization for a manned
glider.

--
Chris Jones    [e-mail]    {world,uunet,harvard}!ksr!clj

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

End of SPACE Digest V12 #514
*******************