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For Want Of A Bolt



 
 
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  #1  
Old September 18th 03, 02:15 AM
Rand Simberg
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Default For Want Of A Bolt

My latest Fox column is up, in which I ruminate on the high cost of
satellites:

http://www.foxnews.com/story/0,2933,97611,00.html

--
simberg.interglobal.org * 310 372-7963 (CA) 307 739-1296 (Jackson Hole)
interglobal space lines * 307 733-1715 (Fax) http://www.interglobal.org

"Extraordinary launch vehicles require extraordinary markets..."
Swap the first . and @ and throw out the ".trash" to email me.
Here's my email address for autospammers:

  #2  
Old September 18th 03, 08:26 AM
Derek Lyons
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h (Rand Simberg) wrote:

My latest Fox column is up, in which I ruminate on the high cost of
satellites:

http://www.foxnews.com/story/0,2933,97611,00.html

From the article:


"But that doesn't explain why similar systems designed for marine use
(the ocean has extremely high positive pressures, and seawater is an
extremely corrosive environment) can be built for orders of magnitude
less."

Please provide a cite of a marine system of the equivalent complexity
and mission of the weather sat with a design lifetime of years or
decades. (Or any marine system with those kinds of lifetime
requirements.)

D.
--
The STS-107 Columbia Loss FAQ can be found
at the following URLs:

Text-Only Version:
http://www.io.com/~o_m/columbia_loss_faq.html

Enhanced HTML Version:
http://www.io.com/~o_m/columbia_loss_faq_x.html

Corrections, comments, and additions should be
e-mailed to , as well as posted to
sci.space.history and sci.space.shuttle for
discussion.

  #3  
Old September 18th 03, 11:28 AM
Dholmes
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Default For Want Of A Bolt


"Rand Simberg" wrote in message
...
My latest Fox column is up, in which I ruminate on the high cost of
satellites:

http://www.foxnews.com/story/0,2933,97611,00.html

I agree that launch costs are too high, satellites costs are too high and
mass production would help.

I have to disagree on one major point.


Launch costs adjusted for inflation have been falling for years while the
average price of satellites have not.
Launch costs are only a small fraction of total costs.
It is the satellites that are not changing to meet lower launch costs not
high launch costs that keep the satellite costs high.


  #4  
Old September 18th 03, 04:51 PM
Rand Simberg
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Default For Want Of A Bolt

On Thu, 18 Sep 2003 01:26:09 CST, in a place far, far away,
(Derek Lyons) made the phosphor on my monitor
glow in such a way as to indicate that:

(Rand Simberg) wrote:

My latest Fox column is up, in which I ruminate on the high cost of
satellites:

http://www.foxnews.com/story/0,2933,97611,00.html

From the article:


"But that doesn't explain why similar systems designed for marine use
(the ocean has extremely high positive pressures, and seawater is an
extremely corrosive environment) can be built for orders of magnitude
less."

Please provide a cite of a marine system of the equivalent complexity
and mission of the weather sat with a design lifetime of years or
decades. (Or any marine system with those kinds of lifetime
requirements.)


You seem to miss the point.

"Those lifetime requirements" are exactly the point. If it were cheap
and easy to get to space, it wouldn't necessarily have those lifetime
requirements.

--
simberg.interglobal.org * 310 372-7963 (CA) 307 739-1296 (Jackson Hole)
interglobal space lines * 307 733-1715 (Fax) http://www.interglobal.org

"Extraordinary launch vehicles require extraordinary markets..."
Swap the first . and @ and throw out the ".trash" to email me.
Here's my email address for autospammers:

  #5  
Old September 19th 03, 06:30 AM
Derek Lyons
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Default For Want Of A Bolt

h (Rand Simberg) wrote:

On Thu, 18 Sep 2003 01:26:09 CST, in a place far, far away,
(Derek Lyons) made the phosphor on my monitor
glow in such a way as to indicate that:

(Rand Simberg) wrote:

My latest Fox column is up, in which I ruminate on the high cost of
satellites:

http://www.foxnews.com/story/0,2933,97611,00.html

From the article:


"But that doesn't explain why similar systems designed for marine use
(the ocean has extremely high positive pressures, and seawater is an
extremely corrosive environment) can be built for orders of magnitude
less."

Please provide a cite of a marine system of the equivalent complexity
and mission of the weather sat with a design lifetime of years or
decades. (Or any marine system with those kinds of lifetime
requirements.)


You seem to miss the point.

"Those lifetime requirements" are exactly the point. If it were cheap
and easy to get to space, it wouldn't necessarily have those lifetime
requirements.


In other words, you have made a claim you are unwilling to back up.

D.
--
The STS-107 Columbia Loss FAQ can be found
at the following URLs:

Text-Only Version:
http://www.io.com/~o_m/columbia_loss_faq.html

Enhanced HTML Version:
http://www.io.com/~o_m/columbia_loss_faq_x.html

Corrections, comments, and additions should be
e-mailed to , as well as posted to
sci.space.history and sci.space.shuttle for
discussion.

  #8  
Old September 23rd 03, 05:58 AM
Lou Scheffer
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Default For Want Of A Bolt

(Derek Lyons) wrote in message ...
h (Rand Simberg) wrote:

"But that doesn't explain why similar systems designed for marine use
(the ocean has extremely high positive pressures, and seawater is an
extremely corrosive environment) can be built for orders of magnitude
less."

Please provide a cite of a marine system of the equivalent complexity
and mission of the weather sat with a design lifetime of years or
decades. (Or any marine system with those kinds of lifetime
requirements.)


Here is from an article describing using an old cable (no longer
economical) for seismic research in mid-ocean (it provides power and
communication).

http://www.terrapub.co.jp/journals/E...2/50110913.pdf

This particular cable was from Guam to Japan and built in 1964. The
cut the cable, dredged up one end, then spliced in a seismometer and
extra cable, then dredged up the other end and connected them. It's
easier than space, but still non-trivial.

"The cable length between two adjacent repeaters is 37.08 km (20
nautical miles). A repeater comprises dual sets of vacuums tube
amplifiers, because vacuum tubes were the most reliable electronic
devices in early 60 s when the system was designed. The first question
was on remaining life of the cable system because the official life of
the system was 25 years. The design lives of repeaters and equalizers,
however, were roughly more than 50 years and the estimated lives of
submarine cables were more than the lives of the electronics (Dodeman,
personal communication). "

Lou Scheffer

  #10  
Old September 23rd 03, 08:13 PM
Henry Spencer
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Default For Want Of A Bolt

In article ,
Lou Scheffer wrote:
Transatlantic cables...


Oops - this was NOT one of the first uses of transistors. Another
article states that they were still built with vacuum tubes in 1964,
10 years after transistors were used for other applications, since
transistors were not yet proven to be more reliable. In retrospect
this makes perfect sense - any reliability conscious field will not
rush to adapt new technology, no matter how promising, if the old
technology is working at least OK.


I'm told that the component-qualification rules for undersea-cable
repeaters make space-qualification procedures look amateurish.
--
MOST launched 1015 EDT 30 June, separated 1046, | Henry Spencer
first ground-station pass 1651, all nominal! |

 




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