Low Cost Shuttle Competition

"W. D. Allen Sr." wrote in message
t...
Right! And my fellow Rockwell employees did a great job for
their time - remember slide rules and T squares?


Sure I worked on designs for Petrochem cracker plants
using them.

But why continue with a forty year old vehicles that are now
falling out of the sky and killing people, especially with
NASA insisting on flying with ice cycles hanging off the
shuttle, leaking booster gas seals, and fuel tanks shedding
insulation?


Because nobody will pony up the money for a replacement.
I imagine NASA would be overjoyed if Congress said
'Go procure a new shuttle - here's $20 billion


We could certainly do it much cheaper, safer, and better
today, right?


Probably but the political will seems to be lacking

NASA's budget for the Shuttle last year was $3.3 billion
enough to buy 2 B-2 bombers, that seems unlikely to be adequate
to fund a replacement

Keith

The real seemingly inescapable problem (I haven't seen an answer in
some fifty years) is that all the real sharp 'Skunkworks' types retire
or get elbowed aside by career bureaucrats whose main thrust in life
is never having to make a single-handed decision, because it might be
wrong and oops there goes the career. Better to place the action in
the hands of a committee (share the blame), wait for someone else to
stick their neck out, or temporize (wait) and hope the problem goes
away or is overtaken by events. In the meantime relie on dubious
statistics to show the problem really isn't that serious in the first
place. Both Shuttle losses can be attributed to this kind of thinking.
- "It's only a few degrees colder . . ."
- "We haven't had any problems with pieces of foam so far . . .
A personnel staffing problem that needs fixing - the question remains
- how? Mybe private industry could do it, but the bean-counters and
short-term bottom-line thinking from the Harvard Business School
eventually killed the Skunkworks . . .
Walt BJ

Remember VenurStar? http://www.fas.org/spp/guide/usa/launch/x-33.htm It
was built by Skunkworks in the late 1990s. The project was canceled after
the propulsion tank failed the test. The tank had to have very complex
shape because it had to fit with in the airframe that resemble flattened
cone. To cut weight, they had to used Graphite composite. The Graphite
composite simply didn't work too well at the liquid Hydrogen temperature.
I mean they had to push the envelop of technology in every area to achieve
single stage to orbit. To date we don't have the material to build such
space ship.

The most efficient single stage vehicle ever built was in 1960s. It was
Atlas. It had 1% throw weight and the tank was made out of .030 inch
stainless steel. Unless the tank was filled with fuel or pressurized the
whole thing would crumple down to scrap metal!

Emilio

"Walt BJ" wrote in message
om...
The real seemingly inescapable problem (I haven't seen an answer in
some fifty years) is that all the real sharp 'Skunkworks' types retire
or get elbowed aside by career bureaucrats whose main thrust in life
is never having to make a single-handed decision, because it might be
wrong and oops there goes the career. Better to place the action in
the hands of a committee (share the blame), wait for someone else to
stick their neck out, or temporize (wait) and hope the problem goes
away or is overtaken by events. In the meantime relie on dubious
statistics to show the problem really isn't that serious in the first
place. Both Shuttle losses can be attributed to this kind of thinking.
- "It's only a few degrees colder . . ."
- "We haven't had any problems with pieces of foam so far . . .
A personnel staffing problem that needs fixing - the question remains
- how? Mybe private industry could do it, but the bean-counters and
short-term bottom-line thinking from the Harvard Business School
eventually killed the Skunkworks . . .
Walt BJ

"Emilio" wrote in message
...
Remember VenurStar? http://www.fas.org/spp/guide/usa/launch/x-33.htm It
was built by Skunkworks in the late 1990s. The project was canceled after
the propulsion tank failed the test. The tank had to have very complex
shape because it had to fit with in the airframe that resemble flattened
cone. To cut weight, they had to used Graphite composite. The Graphite
composite simply didn't work too well at the liquid Hydrogen temperature.
I mean they had to push the envelop of technology in every area to achieve
single stage to orbit. To date we don't have the material to build such
space ship.

The most efficient single stage vehicle ever built was in 1960s. It was
Atlas. It had 1% throw weight and the tank was made out of .030 inch
stainless steel. Unless the tank was filled with fuel or pressurized the
whole thing would crumple down to scrap metal!

Emilio

The Atlas remains in production to this day in the form of the II,III
and V but the design has been continually updated since the
60's and the Atlas now has the highly efficient Russian designed
RD-180 engine.

The RD-180 is a closed cycle engine meaning that the expanding
O2 used to power the fuel pumps is used in the combustion chamber
rather than dumped outboard as is the practise in American engines.

This makes the engine much more efficient. The engine is also
much more powerful than the US engines it replaces and its
throttlable and cheaper. Indeed the RD-180 is likley to power
the new Expendable Launch Vehicles for the USAF

Keith

In article , Keith Willshaw keithNoSpa
writes
The RD-180 is a closed cycle engine meaning that the expanding
O2 used to power the fuel pumps is used in the combustion chamber
rather than dumped outboard as is the practise in American engines.

Is that the one that was subject to a BBC Horizon (or similar) where
some US rocket engineers were shown a warehouse full of engines they
themselves had considered impossible having failed to get them to work?

--
John

Keith Willshaw wrote:

The Atlas remains in production to this day in the form of the II,III
and V but the design has been continually updated since the
60's and the Atlas now has the highly efficient Russian designed
RD-180 engine.

The Atlas V is not a pressure-supported structure - it has an isogrid
tank structure that does not require pressure to support itself. The
II and III essentially use the same pressure-supported tankage as
before, lengthened and adapted as necessary.

"John Halliwell" wrote in message
...
In article , Keith Willshaw keithNoSpa
writes
The RD-180 is a closed cycle engine meaning that the expanding
O2 used to power the fuel pumps is used in the combustion chamber
rather than dumped outboard as is the practise in American engines.

Is that the one that was subject to a BBC Horizon (or similar) where
some US rocket engineers were shown a warehouse full of engines they
themselves had considered impossible having failed to get them to work?

--
John

Sadly "Horizon" has been noticeably "dumbed-down" of late, preferring
hyperbole to subtlety, relishing in constantly trotting out the same
"established scientists said it couldn't work/happen/exist, but these
renegades/upstarts/FSU-engineers have proven them wrong" line whether the
programme is about dinousaurs, rockets, asteroids or aircraft. Rockets are
not my field, but I am given to understand that the SSME (noticeably
American when I last checked) is a closed-cycle design.

"John Halliwell" wrote in message
...
In article , Keith Willshaw keithNoSpa
writes
The RD-180 is a closed cycle engine meaning that the expanding
O2 used to power the fuel pumps is used in the combustion chamber
rather than dumped outboard as is the practise in American engines.

Is that the one that was subject to a BBC Horizon (or similar) where
some US rocket engineers were shown a warehouse full of engines they
themselves had considered impossible having failed to get them to work?


Yep

Keith

"NoHoverStop" wrote in message
...
"John Halliwell" wrote in message


Sadly "Horizon" has been noticeably "dumbed-down" of late, preferring
hyperbole to subtlety, relishing in constantly trotting out the same
"established scientists said it couldn't work/happen/exist, but these
renegades/upstarts/FSU-engineers have proven them wrong" line whether the
programme is about dinousaurs, rockets, asteroids or aircraft. Rockets are
not my field, but I am given to understand that the SSME (noticeably
American when I last checked) is a closed-cycle design.



The statement about the US having abandoned close cycle engines was
made by one of the US engineers who was involved with licensing
the rocket motor design from Energomash and in this instance I
dont recall any rubbishing of US efforts by the program maker.

The Channel 4 web site carries the same story by the way stating

http://www.channel4.com/science/micr.../timeline.html

Quote

US rocket scientists are taken to see stored NK33s.

Scientists from the US company Aerojet are amazed to find a store of over 60
pristine engines, of a compact design that they had never seen before. What
surprised them most was that the engines used the closed-cycle technology
that had been rejected by American rocket scientists as being too risky.

/Quote

As does wired.com

http://www.wired.com/wired/archive/9.12/rd-180.html

It agrees that the SSME has a closed cycle engine but states that its
the exception and of course the SSME is quite unusual in being
a restartable engine. Most rocket engines are one shot devices.

Keith

In article ,
"Keith Willshaw" writes:

"NoHoverStop" wrote in message
...
"John Halliwell" wrote in message


Sadly "Horizon" has been noticeably "dumbed-down" of late, preferring
hyperbole to subtlety, relishing in constantly trotting out the same
"established scientists said it couldn't work/happen/exist, but these
renegades/upstarts/FSU-engineers have proven them wrong" line whether the
programme is about dinousaurs, rockets, asteroids or aircraft. Rockets are
not my field, but I am given to understand that the SSME (noticeably
American when I last checked) is a closed-cycle design.



The statement about the US having abandoned close cycle engines was
made by one of the US engineers who was involved with licensing
the rocket motor design from Energomash and in this instance I
dont recall any rubbishing of US efforts by the program maker.

The Channel 4 web site carries the same story by the way stating

http://www.channel4.com/science/micr.../timeline.html

Quote

US rocket scientists are taken to see stored NK33s.

Scientists from the US company Aerojet are amazed to find a store of over 60
pristine engines, of a compact design that they had never seen before. What
surprised them most was that the engines used the closed-cycle technology
that had been rejected by American rocket scientists as being too risky.

/Quote

As does wired.com

http://www.wired.com/wired/archive/9.12/rd-180.html

It agrees that the SSME has a closed cycle engine but states that its
the exception and of course the SSME is quite unusual in being
a restartable engine. Most rocket engines are one shot devices.

That's not quite true, Keith. Thus far, all U.S. liquid rockets for
space boosters, anyway, have been reusable to some extent. They're
all proff-fired before use. Some, such as the RL-10 have demonstrated
(in ground testing) the ability to be restarted over 30 times.
We just haven't been using them that way.
Most booster engines, with the exception of upper stages for systems
that will need to change orbit, like, say, an Apollo leaving parking
orbit to go to the Moon, or a Mars Probe, or such, aren't restartable
in flight. Once they are lit, you can turn 'em off, but there's not
way to get them lit again.

I think there may be a bit of overstating the case here, too. It's
not so much that a closed-cycle engine is _that_ much more difficult,
but it does reflect a different design philosophy than most
U.S. rocket manufacturers have used. The again, nearly all
U.S. liquid fuelled rocket motor are either late 1950s designs, or
derivitives of designs from the late 1950s and the 1960s. There've
been plenty of incremental improvements, but not a lot of new
development.

--
Pete Stickney
A strong conviction that something must be done is the parent of many
bad measures. -- Daniel Webster