Of tanks, foam and culture

I read the articles above. Discounting the range safety one as it was pre
Columbia, and I think, a different issue, I do feel that the one question
which is never going to be answered is,'how much foam can you lose'. Seems
to me that if you want to be brutally honest, there is a design flaw, and
all you can do is patch it up so that minimal size of the shed areas is
below catastrophic damage constraints. However, nobody really knows what
these parameters are.

The problem is that early in the program, the culture was far worse than
now, in that they flew it without detailed knowledge of what a big hit might
do, and they got away with it more than perhaps they had a right to.

Now however, you have on the one hand a commitment to finish the job of
building the space station, competition for funds, an aging vehicle and a
sudden awareness that you have an insurmountable problem.

If you then have people willing to fly it and everyone breathing down your
neck, what do you do?

Has anyone ...
A: found out what settlement you could get with the international partners
if you said you could not fulfil your part of the deal?
B: thought about seeing if any of the equipment could be flown on
conventional rockets?

Talked to the partners about some form of compromise where the US would pay
dev. costs for them to build a launcher to carry the parts to orbit.

Seems to me that the ISS is a white elephant itself, and maybe a smaller
system perhaps several, might be a better answer.

Brian

--

From my IMAP account
Brian Gaff

Why has the foam loss got worse after 2 years and billions of dollars
spent to fix it?

from florida todays space blog:

First RTF flight took more foam hits
Discovery endured more foam debris hits than average on the first
post-Columbia mission. The damage sites were not as deep, but the
number (176) is above the average (144) over the 25-year life of the
shuttle program. That's one of several data points in a report in this
morning's Florida Today regarding the decision to launch last year's
return to flight mission and the parallels to decisions being made in
the runup to the next flight this summer.

You can read the foam story here and a summary of what other
independent reviewers have said on these issues here. For those who
like to read detailed documentation, the stories include links to some
of the studies and reports that we reviewed. Most are
previously-released documents made public in the nine months since the
accident. One not available anywhere else yet is the final post-flight
inspection, which some call the "ding report." Check it out here. The
other documents can be downloaded from links in the stories noted
above.

posted by John Kelly

Then we have the publics perception of the money pit err station:

Space station too weighty for NASA?

By Howard Witt
Tribune senior correspondent
Published March 27, 2006


HOUSTON -- This Wednesday evening, if all goes according to plan, an
American astronaut and a Russian cosmonaut will blast off aboard a
Russian rocket headed for the International Space Station, the latest
crew in an uninterrupted procession that has kept humans aboard the
station for more than five years.

And if all goes according to routine, outside of the professional space
community and a handful of space enthusiasts, few Americans are likely
to even notice. The workaday space station, far less dramatic than a
space shuttle mission and far less compelling than planned journeys to
the moon and Mars, long ago ceased to command much public fascination.

But the half-built space station continues to command a large chunk of
NASA's operating budget, even as President Bush and Congress have
directed the space agency to shift its focus to a return to the moon by
2020 and a journey to Mars after that. Now, to help cover the cost of
completing the orbiting outpost that is supposed to serve as a unique
platform for scientific research, NASA is slashing its science budget
by $3.1 billion.

In a decision that some critics liken to the space agency eating its
young, NASA announced last month it was canceling numerous experiments
that were planned aboard the station to help future astronauts survive
long-duration missions to the moon and Mars. Several robotic probe
missions to distant planets also were scrapped, as well as funding for
hundreds of space researchers at universities across the country.

"The space station was sold to Congress for decades as a lab to do this
kind of broad-based research," said Keith Cowing, a former NASA
engineer and editor of nasawatch.com, a Web site often critical of the
space agency. "Now they've started gutting the station just when it is
at the point of being able to do all the things it was supposed to do.
That leaves the purpose of the space station as something for
astronauts to fix."

NASA administrator Michael Griffin said earlier this month that he
regretted having to cut the agency's budget for scientific research,
but that he was left no choice by the combined costs of 16 more shuttle
missions to complete the space station by 2010 while simultaneously
beginning design and construction of next-generation rockets and
vehicles to take astronauts to the moon and Mars.

"We focused on redefining the station assembly sequence in fact to
concentrate on assembly, and we are largely deferring utilization and
we are paring logistics to the bone," Griffin told reporters at the
Kennedy Space Center in Florida. "We don't like that, but confronted
with a choice between having a high confidence to be able to complete
the assembly of the station and deferring utilization, or utilizing it
heavily as we built it and possibly not finishing, we chose the former
course."

Falling short of promises

Some scientists contend that cutting NASA's research grants will drive
experts out of the space field and cause long-term damage.

"Fifteen or 20 years from now, NASA will have a space station and
vehicles to go to Mars and no researchers to answer the questions of
what do we do when we get there," said Simon Ostrach, an emeritus
professor of engineering at Case Western Reserve University whose
former research center is among those losing NASA funding.

Conceived decades before Bush in 2004 set NASA on a new quest toward
Mars, and requiring the heavy-lifting capabilities of the balky and
aging shuttle fleet in order to complete it, the 206-ton station orbits
Earth every 92 minutes.

Less than 40 percent complete eight years after construction began, the
station has by some estimates already cost more than $50 billion, yet
it still can't accommodate more than three crew members--enough to
operate and repair the station but only half the number needed to
conduct a full schedule of research and experiments.

Some critics argue that the space station has become a white elephant
that is forcing NASA to extend the risky shuttle program--two orbiters,
Challenger and Columbia, and their crews have been lost to
explosions--while diverting funds from unmanned missions to Mars and
other planets that have proven more scientifically fruitful. Neither is
the station essential as a jumping-off point for sending humans back to
the moon or on to Mars, they say.

"I don't place the space station in the critical path for sending
humans to the moon," said Wesley Huntress, director of the geophysical
laboratory at the Carnegie Institution of Washington and a former NASA
associate administrator for space science. "And frankly the science
community will tell you it was never a very useful platform for doing
science at all. It's not in the right orbit for lots of things, and
it's a very noisy environment."

NASA officials say they are utilizing the space station as much as
possible for experiments to understand the effects of long-term
spaceflight on the human body. If humans are to endure years-long
missions to Mars, researchers must find ways to protect them from such
known issues as radiation exposure and bone and muscle loss due to low
gravity.

Scaling back on studies

"We have tried to give the highest priority to the research that we
need to get to the moon and Mars and beyond," said astronaut Donald
Thomas, the space station's program scientist. "Is the science scaled
back? You bet it is. But is it no science at all? No. We're still
trying to utilize this station all we can up there."

But a National Research Council review of NASA's space station plans in
November criticized the space agency for failing to define how the
station can be used to conduct research in support of long-duration
space missions. And among the science programs recently cut by NASA
were plant and animal research that might have answered such questions
as how astronauts on the moon and Mars could grow their own food. A
large centrifuge that could have duplicated the low-gravity conditions
on the moon and Mars also was scrapped from the list of space station
experiments.

"The decision to remove fundamental science removes animal studies that
were directly relevant to problems humans would experience for longer
periods in space," said Mary Jane Osborn, a professor at the University
of Connecticut Health Center and chairwoman of the council's review
panel. "All in all, the situation looks at least as bleak if not
bleaker than it did last November."

Despite the science cuts, NASA officials insist they remain committed
to the space station. Yet at Space Center Houston, the Johnson Space
Center's visitor center and one of the agency's showcase attractions,
the space station feels like an afterthought.

Faulty showcase

A big-screen film about the space station was made in 2000 and heralds
projects such the Crew Escape Vehicle and the Orbital Space Plane that
have since been abandoned. A virtual reality tour of the station
features broken computers and graphics that pale in comparison to the
simplest video games.

Even if NASA wanted to back away from the space station, officials say
that promises made to 15 nations participating in the project compel
the United States to complete the station's construction. Russia,
Canada, Japan and the European Space Agency have all spent billions on
space station modules and experiments that require launch aboard the
space shuttle.

One area that has not been cut from the space station is product
placements and commercial publicity stunts, which generate cash for the
partner nations.

This summer, a Russian cosmonaut is scheduled to hit a gold-plated golf
ball off the station during a spacewalk in a promotion for a Canadian
golf club manufacturer. In 2001, Pizza Hut paid the Russians to deliver
a pizza to the space station.

----------



Then we have Japan considering a pull out over costs:

Daily Yomiuri

"The government should take the U.S. postponement of the next space
shuttle launch and its potential impact on the building of the
International Space Station more seriously. ... Prospects for a
successful completion of the program are dimming. The issue is not only
about space shuttle launch costs. Tokyo will be responsible for annual
ISS running costs of about 40 billion yen [~$340 million USD], although
it has not been determined how many years the station will remain
operational after it is completed."

Posted by kcowing at 12:11 PM |

"Brian Gaff" wrote:

:Has anyone ...
:A: found out what settlement you could get with the international partners
:if you said you could not fulfil your part of the deal?

Probably be cheaper to just take the risk and fly them.

:B: thought about seeing if any of the equipment could be flown on
:conventional rockets?

Some of them are too big.

:Talked to the partners about some form of compromise where the US would pay
:dev. costs for them to build a launcher to carry the parts to orbit.

This one is merely crazy. Developing the launcher is the expensive
part. If we had the funds to do that, why would we want to give them
to someone else to do the job?

:Seems to me that the ISS is a white elephant itself, and maybe a smaller
:system perhaps several, might be a better answer.

Well, there is that. ISS as built is not what we originally set out
to do. Too many redesigns, rescopes, etc.

--
"It's always different. It's always complex. But at some point,
somebody has to draw the line. And that somebody is always me....
I am the law."
-- Buffy, The Vampire Slayer

"Brian Gaff" wrote in message
k...
I read the articles above. Discounting the range safety one as it was pre
Columbia, and I think, a different issue, I do feel that the one question
which is never going to be answered is,'how much foam can you lose'. Seems
to me that if you want to be brutally honest, there is a design flaw, and
all you can do is patch it up so that minimal size of the shed areas is
below catastrophic damage constraints. However, nobody really knows what
these parameters are.

In CAIB hearings they said the original spec was 0.006 foot pounds per
impact, maximum. That's so small it means virtually no impacts.

At first NASA probably assumed it would be solved, then after the first
missions, became accustomed to it (normalization of deviance).

Because of Columbia they want to totally solve the problem.
But even if not completely solved, with the few remaining flights,
and going only to ISS (except possibly one Hubble mission), the risk
of fatality from foam-induced TPS problems seems relatively
small. Unless they have an abort, ISS will do a thorough TPS inspection.
The Hubble mission will be different, but it's just one mission, and they
have other techniques for inspecting it.

So even if the foam shedding problem isn't totally solved, it seems
livable considering the limited remaining flights. You have to take
some risks. Everybody is focusing on TPS, but ascent-related
problems (SSME, APU, etc) are still probably a greater risk.

-- Joe D.

The caib's final conclusions lacked correlation of actual data
detecting cause (foam impact of the magnitude on jan 16, 2003 by on
board sensors), to their theorized effect (forces imparted by impacting
foam to at a great enough magnitude to cause rcc damage). Nor did the
caib provide correlation damage amongst its many test results for
thermal events, and actual damage caused by the foam to the flight day
2 object (140 sq inch object) that represented fragments of the alleged
impact.

Listed below are 2 examples of the caibs lack of correlation of actual
data detected on coumbias ascent jan16, 2003, and foam impact damaging
columbias wing to the extent claimed in their foam impact theory.

#1 Please see graphs pertaining to the accelerometer on the left wing
elevon (V08D9729A), (Caib report vol5 part d13 page 604,605)
At 0.13 seconds after impact excitation the magnitude of the wave
detected by the accelarometer from impact testing is matching the wing
3rd bending mode in magntude and period, where the signal should have
been detected by columbias on board accelerometers on jan 16 2003.
Please note foam impact FI=0 at MET +81.9 seconcd, and the graph listed
by the caib on page, shows the wave closest matching the wing 3rd
bending mode and dampening at a slow decreasing rate, meaning at MET
+82 seconds the impact excitation wave was still detectable by
accelerometer (V08D9729A) sampling at 10 times a second. Instead the
caib states “the most compared� is the 2nd wing bending moment,
which completely disregards the closer match of 3rd wing bending moment
to the excitation pattern from the force of impact. Then the caib
states the differences between test results and actual sts-107 flight
data could be caused by difference of impact location, as the reason
for not aknolegding the 2nd wing bending mode.

#2 Foam impact was determined to have occurred at MET +81.9, the
detailed examination by boeing determined excitation in the wing
started at MET +81.7, 0.2 seconds before foam impact, thefefore foam
impact was not the stimulation for the force revealed from boeings’
analysis from data during sts-107’s ascent on jan 16, 2003.

The caib did not provide or demonstrate a correlation to the
columbia’s on board sensors detecting a foam impacting to the
magnitude required for rcc failure on jan 16 2003, and their own foam
impact testing, therefore the caibs theory has not been validated.

caib report vol v part 13 page 608 par 1
“7.3.3.1 Ascent
All STS-107 MADS PCM strain data, without exception, was nominal during
the ascent flight regime. Nosignificant anomalies were noted.
Comparison of ascent strain gage load indicators showed STS-107 ascent
loads to be within the family of previous OV-102 flight experience.
There was no discernable evidence of an impact load to the vehicle near
MET +81.7 seconds. At the PCM sample rate of 10 samples per second, no
such evidence is expected to be present. Both the extremely short
duration of the impact load (0.003 to 0.005 seconds), and the range of
wing modes (6 Hz and above) preclude such evidence. An interesting
signature near this time was evident in some strain gages. The response
was noted on left wing, right wing, and vertical tail gages. Further
study and scrutiny showed that the signature was inconsistent with
impact loading, and attributable to a nominal ascent load response. A
review of accelerometer data did show signatures consistent with impact
loading. This assessment is discussed in Section 7.4.�

Caib report vol 1 page 34 col 2 par 3
“Debris Strike
Post-launch photographic analysis showed that one large piece and at
least two smaller pieces of insulating foam separated from the External
Tank left bipod (–Y) ramp area at 81.7 seconds after launch. Later
analysis showed that the larger piece struck Columbia on the underside
of the left wing, around Reinforced Carbon-Carbon (RCC) panels 5
through 9, at 81.9 seconds after launch (see Figure 2.3-2).�

caib report vol 2 part d19 page 567-568 col 2 par
The wideband FDM data, which because of its more com-plex encoding took
longer to extract from the OEX recorder tape, also showed some
signatures which are indicative of a debris strike near to 82 sec MET.
One of the accelerometers on the left wing elevons, V08D9729A, showed a
single cycle sinusoidal pulse at 81.9 sec MET that was approximately
2 g in amplitude, as compared to a background vibration level which
generally stayed well below 1 g. This is a fairly sig-nificant pulse
which could easily represent a strike of foam debris upon ascent. The
timing and amplitude of this pulse were taken from a preliminary
assessment of the wideband
FDM data that was printed out on a strip chart recorder by NASA at JSC.

Boeing of Huntington Beach performed a more thorough analysis of the
remainder of the wideband FDM ascent data and in general did not find
much that was anomalous. They found that the overall noise levels and
power spectral density (PSD) matched very closely to the data from the
pre-vious flight, STS-109. They noticed that at approximately 40 sec
MET, the vertical stabilizer had some of its higher order modes growing
slightly larger than normal, and this was attributed to some wind
buffeting that was thought to occur around this time. These modes then
decayed shortly thereafter, indicating that the so-called flutter
instability was not becoming excited, as can occur when the wing
bending modes and the fuselage vertical modes coalesce into a single
coupled oscillation. Boeing.s analysis also pointed out that the
recorded accelerations along the longeron were normal. Detailed
analysis of the wideband FDM data over the time frame around 80-85 sec
MET was performed. For the left outboard elevon accelerometer,
V08D9729A, several wing and elevon oscillation modes were found to be
excited during this time, with the strongest being a second order wing
bending mode that matched best to the fundamental component of the
single cycle sinusoidal pulse at 81.9 sec MET. Boeing.s more detailed
time scale showed the period of the single sinusoidal pulse to extend
over 81.70 to 81.74 sec MET, reaching +3.0 g on the positive peak at
81.71 sec MET, and ï€*2.6 g on the negative peak at 81.72 sec MET.
In addition, another accelerometer on the right wing, V08D9766A,
showed a 1.5 cycle sinusoidal pulse response at a slightly earlier time
of around 80 sec MET. This accel-erometer was located at the
coordinates (X1367.0, Y+312.0, Z) towards the middle of the right wing
and was sensitive to Z-axis motion. This accelerometer recorded an
anomalous pulse beginning at 80.22 sec MET, growing to a first positive
peak of +1.5 g at 80.23 sec MET, reaching a negative peak of ï€*1.9 g
at 80.24 sec MET, then another positive peak of +2.0 g at 80.26 sec
MET, before dying away beyond 80.27 sec MET. The best fit to these
peaks was a combination of outboard elevon torsion and the first wing
bending mode. There have not been any explanations offered for the
cause of this right wing accelerometer response. “


Caib report vol5 part d13 page 602
7.4.1.1 Evaluation of Peak Response at ~82 Seconds
An in-depth study was made to investigate if the peak responses
observed at the left outboard elevon accelerometer at ~82 seconds is
due to the debris impact. Normally, sharp spikes in acceleration are
observed at times during the ascent phase of the flight due to
buffeting event(s). The buffeting load is most significant during the
transonic region. However, it still exists at higher Mach numbers,
which resultsin structural excitation. Shown in Figure 7.4-7 is the
left and right outboard elevon comparison for the 10 second period near
82 seconds. The peak response is noticeable only for the left outboard
location. Filtered responses presented in Figure 7.4-8 verify several
wing/elevons were excited at 82 seconds. The 2nd wing bending response
constitutes the largest component of the peak amplitude. In addition,
the responses of 3rd wing bending and elevon torsion modes contributed
to the peak response.

Caib report vol5 part d13 page 603
“To determine if the debris impact can cause the type of responses
observed in the flight data, analyses were performed using the FEM
model of the wing combined with the reduced model of the Orbiter, which
provides the back-up structure’s stiffness and mass (Figure 7.4-9).
An impulse of 3,000 lbs force (with 0.005 second duration) in
Z-direction was applied to the node closest to the RCC panel #8. The
impulse of this magnitude is reasonable for a 1.5 lb object with a
velocity of 530 MPH impacting the surface at 15 degrees inclination.�

Caib report vol5 part d13 page 604
“Shown in Figure 7.4-10 is the recovered acceleration at the left
outboard elevon location from the transient analysis. The FFT (Figure
7.4-11) of the response indicates excitation of several wing modes,
including wing’s 2nd and 3rd bending modes. The filtered responses
shown in Figure 7.4-12 illustrate the 3rd wing bending mode constitutes
the majority of the peak amplitude, while the 2nd wing bending and
elevon torsion modes also contribute to the peak response. The
acceleration computed using the FEM model is shown along with the
flight measured data in Figure 7.4-13. The shapes of acceleration
signatures are comparable at the onset of debris impact. The frequency
from the analysis is higher, since the 3rd wing bending mode is excited
the most compared with the 2nd wing bending mode experienced during
STS-107. More pronounced 3rd wing bending response from analysis could
be attributed to possible deviations from the assumed location and
duration of impact event, and some uncertainty in the FEM models for
higher order wing modes. Nevertheless, similar acceleration signature
and the excitation of higher order wing modes from the analysis
indicate that the debris impact quite possibly could have caused the
peak acceleration on the left outboard elevon at ~82 seconds in
addition to other aerodynamic disturbances, such as buffeting and
shocks. An absence of additional sensors on the left wing make it
difficult to make conclusive remarks.�