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To be added:
AntiGravity
Failure Mechanisms
Cosmic Life Line
Sci Study of UFOs
Solo Sapiens
Philosophy of Science
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Shuttle = The Space Shuttle
Factor = One Mistake that Produced A Thousand Problems and
Ruined the Space Program
"Dynamic
Overshoot" In "Space Systems"
The following 4 documents can also be found on www.nasa.gov
/ Human Space Flight Committee (Augustine Committee)/Related Documents.
"The National Academies, NSF, GAO and others agree today that “knowledge
gaps” and shortcomings in science, technology, engineering and mathematics
(STEM) subjects have undermined modern systems, especially, space systems. The
shortcomings produced cost overruns, schedule slippages, problematic operations,
expensive maintenance, short life and random failures. Bridging the knowledge
gaps is vital to reinvigorate our space program, economy, education and world
leadership."
"My transient
“dynamic overshoot” studies caused controversies since 1986. The Report I
submit for the Committee’s consideration on this subject is rather lengthy. To
counter detractors, I found it necessary to discuss the ontological reality and
epistemological foundation of the phenomenon, include overwhelming empirical
evidence, straightforward mathematical analysis, sobering line of reasoning, and
many relevant and, perhaps, irrelevant, opinions to shore up my case. It remains
my opinion that the transient dynamic overshoot phenomenon has been the primary
problem with the Space Shuttle and the Space Program."
"According to Heraclitus, the advocate of change, nature loves to hide,
for example, 30m waves. The study of huge sudden rogue waves by Chris
Garrett and Johannes Gemmrich (physics today, June 2009, page 62) describes a phenomenon
that is difficult to reproduce in the laboratory and resistant to mathematical
analysis. Relevant to this subject, I did extensive research in the
1980s-90s,
which resulted in the Patent, “Method for Producing Natural Motion.” In
many tests, I produced sudden extra-large waves by straightforward
modulation of waves, as described below. This has not been done before."
"There is a conspicuous “knowledge gap” between the Galilean-Newtonian
mechanics and modern energetics. This is the sudden jump taken from the concept
of force to the energy conservation principle, which should be familiar to all
physicists and engineers. According to the textbooks, the sudden jump is taken
to simplify problem solving. But failing to bridge the “gap,” 20th
century classical physics remained incomplete and modern physics lacked a vital
cornerstone in its development. The last serious attempts to bridge the gap were
taken by Hertz, Mach and Boltzmann at the end of the 19th century,
but as noted by Einstein, Poincare and others, the central problems were not
resolved."
The Problem with the Space Shuttle and the Space
Program [Shuttlefactor]
Detailed explanation of the transient dynamic overshoot
effect
1992, 2000, 2003 (PDF 970KB)
Postscript August 25, 2009
The Obama Administration is facing another daunting task
– the space program – not unlike the overwhelming tasks that it has
undertaken with the economy, health care, education, etc. Some advocates of
human space flight want the President to commit the Nation to go to Mars right
away. Build the Ares-I rocket. Build the big Ares-V rocket. Pack it up, and
let’s go. Some want us to go back to the Moon soon. Only a few sober voices
seem to realize the stark fact that we can hardly send humans to Low Earth Orbit
(LEO) reliably and economically. And the “gap” is staring us down, i.e., we
will buy seats on Russian rockets to visit one of our big investments, the
International Space Station. The problems are many and deep-rooted. The space
Initiative of only 20 years ago promised to return us to the Moon in 2004, which
didn’t happen, go to Mars in 2014, which will not happen, and have a thriving
space program by now (2009), which it isn’t. The 5-year old space Vision is
already in trouble. What’s going on? How did all of this come about? What’s
the way out?
For those of us who worked in the space program in the
1960s and 70s, something seems farcical about the present situation. Back then,
we did not have space textbooks or handbooks, we didn’t have desktops or
laptops, we didn’t even have hand held calculators. Similar hi-tech tools were
not available to the economists, but the economy prospered. Yet, with all the
modern tools, the economy nearly collapsed last year. Is our space program on a
down turn that can be quickly turned around? Or, is it near, or in, a meltdown
condition?
I don’t think anyone could have predicted the economic
crisis of 2008 twenty years ago. But, engineering is a precise art, and one can
predict the consequences of major mistakes, or outright blunders. This lengthy
Report describes such a blunder; I call the dynamic overshoot, or dynamic
transient, effect. Get a cheap slinky, put a weight on one end, hold part of the
slinky in your hand and release the weight: Watch carefully and think about it;
you will recognize the “dynamic overshoot.” This Report describes with ample
evidence how one mistake undermined the whole space program.
In a meeting with a large group of engineers at the Kennedy
Space Center in October 1986, I discussed the “dynamic overshoot” mistake in
detail. The Director of Shuttle Engineering asked for a copy of my written
notes. In those notes, I asked in writing, “Are there instruments to
measure transient response to step-input?” (See Figure 67). The transient
behavior of the Shuttle was completely messed up from the start. I subsequently
mounted a massive and expensive effort from 1986 to 92 to describe the mistake
and its consequences to the White House, the Congress, the Aerospace
Contractors, the Professional Organizations, the Universities and the media, as
you will read about in this Report.
Later this week, the new Ares-I rocket will be tested.
I ask my above 1986 question again, “Are there instruments to measure
transient response to step-input?” The magnitude of the “dynamic
overshoot” effect, particularly for solid rocket motors, is so massive that
the White House, the Congress and the American public must know the exact
“dynamic overshoot” measured for the Ares-I. Will the “dynamic
overshoot” be measured? Will it be measured correctly? How will the
measurements of Ares-I differ from the hodgepodge guesses used with the Space
Shuttle? Was the “dynamic overshoot” calculated, and computer simulated,
correctly before the test? How will the test results compare with the calculated
and computer-generated values?"
"Have you ever had your car repaired for the same problem 3, 5, or 7 times?
The mechanic explains the reasons for changing a part under the hood; you
understand and pay the bill. Then another part, another bill, yet the problem
persists. You go to a shop with ultra-modern equipment, they change other parts,
more bills, but the problem lives on. Finally, you pull into a simple shop on a
country road and a friendly fellow makes a simple adjustment, explains the
reason for the adjustment, a small bill; to your unexpected delight, the problem
is gone. The same scenario happens to people with the heating, electrical, water
or other systems in their homes. The aerospace-structural-dynamics experts will
shout that the analogy is not fair. It is. If you do not know the cause of a
problem, you will run around in circles fixing the wrong things, while the
causal problem lives on. The devastating dynamic overshoot 100% mistake lives
on."
"The deep roots of the “dynamic overshoot” mistake are discussed in this
Report. The discussion includes scientific, technical, educational, historical,
philosophical, psychological and political elements of the design blunder. The
Report shows (1) how some engineers are completely unaware of the “surge”
effect in physical systems, (2) how some engineers miscalculated and mishandled
the effect in Shuttle design, (3) how the engineers actually measured the
correct “surge forces” in the Shuttle in 1982, but did not even realize the
meaning of the correct measurement, (4) how Newton’s Action-Reaction Law is at
the root of the problem, (5) how scientists and engineers mistakenly and
regularly equate the cause and effect,
input and output, action
and reaction, and forcing
function and transient response
in mechanical start-up transient situations, and (6) how relying nearly
exclusively on pressure measurements (which do not show the “surge” effect),
physicists and rocket engineers repeatedly fell into the tricky “dynamic
overshoot” trap, with drastic results."
Back to Top
From
"Space Systems" to "Nuclear Reactors"
The
Correct Way to Handle Transient Loads
May 19, 1993
Early in the
century, the explosion of temperamental boilers killed people and destroyed
industrial and residential centers. Halfway through the century, jet
powered aircraft crashed unexpectedly, killing people and causing considerable
losses. In the beginning of the space program, the
hallmark of rockets was the huge explosions soon after ignition and the
destruction of valuable payloads and launch facilities. Then there were the
nuclear reactor incidents: Three Mile Island (TMI) which frightened a large
community and a nation, and Chernobyl which devastated communities and shocked
the world. What these systems have in common is that they are
pressure-activated, and the mechanical engineer plays the central role
in their design, construction, operation, safety, and reliability. Where are
we today?
Have we (mechanical engineers) overlooked something
fundamental in our work? The answer is a resounding yes. One basic error has
undermined the safety, reliability
and economy of important systems throughout the century.
…The nature of the error can be appreciated from the
observation that the pressure does not overshoot, nor should it be expected to
overshoot.
…The boosters were repeatedly strengthened, particularly,
after the Challenger accident; and the number of uses should have gone up, and
not down. Yet in 1990, three segments
failed irreparably after only one (1) mission. At this rate, we are not
going to Mars; we are not going back to the Moon; and we will hardly
make it to low earth orbit; which is where we are today (May 19, 1993).
Something is fundamentally wrong in mechanical
engineering. Something is fundamentally wrong in the mechanical curricula and
textbooks. A radical change in mechanical engineering education and practice
must take place to remedy the fundamental oversight.
Transient
Loads in Nuclear Power Reactors
Letter to ASME, May 20, 1993 (PDF 650KB)
…to
find some 20 pages that will highlight the problem, particularly, in pressure
vessels, including, nuclear reactors as we discussed yesterday. Most of the
papers are lengthy, with greater emphasis on the same problem in aerospace
systems, and include specific numerical examples from real systems. I believe
the enclosures and the following commentary will provide a glimpse of how the
transient loads have been [mis]handled in nuclear reactor pressure vessels and
related hardware. I will be glad to answer your, or other experts’,
questions.
There
is no indication whatsoever that the pressure-time profiles are the forcing
function in transient conditions.
This
is fine if the transient is measured separately and directly. But, the
transient parameters are not even included. The pressure measurement is
strictly the “forcing function” and it must be used to derive the
transient response analytically, which then requires interpretation.
While
most other papers that I have reviewed show simple conversion of pressure to
stress, this paper shows that the “transient” concept is very seriously
muddled.
Similar
curves are very popular in aerospace systems. Actually, they are the only kind
available for rocket engines and motors, jet engines, etc. The measured
pressure very nearly tracks some computer predictions. Well of course they
should. The two are the same parameter!
I
recommend that you do not accept the common clichés: We know about
transients; We always take the forcing function and derive the response, etc.
If the forcing function and the response look like the curves shown in the
enclosures, then the transient is not understood, let alone derived.
Yet,
not one single paper presented a true “transient response.” I emphasize
again that a pressure measurement shown to be similar to some computer code,
or vice versa, is not a transient analysis. It is the same parameter shown to
equal itself, which it should.
See also, “Radiation Embrittlement
and Surveillance of Nuclear Reactor Pressure Vessels: An International
Study,” Conference sponsored by IAEA, ASTM Committee E-10, 1981; and similar
references.
Safety
of Nuclear Power Reactors In Transient Conditions
Letter to Dr. Stanislav Fabic, June 3, 1993 (PDF 925KB)
Reference
to your letter of May 29, 1993, it concerns me a great deal that you could not
recognize the enormity of the widespread error described in my write-ups. The
safety, reliability and economy of important systems, including nuclear
reactors, have been (and continue to be) severely compromised by the lack of
understanding of transient loading conditions. This is not simply a matter of
“a different opinion about causes-and-effects;” it is about a clear
understanding of the causes and the effects, as they are. Since your views
will be persuasive to the NRC, ASME, and others, I will clarify some matters
and I hope that you reconsider your earlier conclusion.
…a
clear distinction must be made between the pressure (cause) in a vessel, and
the stress (effect) in the materials that make up the vessel.
…that
the force magnification I propose is like “getting something for nothing.”
I am including a couple of pages from Machine Design and Vibration textbooks,
which show the doubling effect. In two simple steps, the equations simplify
to: F = 2F!!
It
just happens that in all the technical papers and the panel
discussions, in which you participated, on the safety of nuclear reactors in
transient conditions, the stress is derived directly from the pressure
readouts. The stress simply follows the pressure. There is no overshoot in
the stress. This means that there was no transient analysis whatsoever,
correct or otherwise; even though the word “transient” was widely used.
The practice was done even when the pressure build-up occurred in less than 10
milliseconds. At this rate, Sir, the “forcing function” is nearly a
unit-step-function; and correct transient analysis will show that the effect
of the load on some parts of the system is nearly doubled… The
pressure-time curve is not the transient response.
The
problem is trivial, but it is not obvious, though it is very important.
You
are thinking in terms of pressure fluctuations, which you call in your letter
“pressure overshoot.” This is a central part of the problem. The
pressure does not overshoot. My weight does not magnify when I step suddenly
on a weight scale… there is a distinct difference between the pressure
fluctuation and the force overshoot. These differences have not been taught at
the undergraduate or other levels.
Other transient experts recently dismissed my assertions out of hand because
they say that modern pressure transducers are extremely sensitive and, hence,
must pick up the transient response. Please refer to my enclosed figures (6a).
The pressure transducers do not, and cannot, measure nor detect the
overshoot! These experts consider my assertions idiotic. I repeat, the
pressure transducers do not, and cannot, measure nor detect the overshoot!
Shock
Absorbers and Damping Isolators for Space Systems
September 1993
A conspicuous dynamic effect
exists when a car is driven over a speed bump, such as found in
parking lots. Once the speed bump is safely cleared, the car encounters lesser
dynamic conditions in a typical journey. Without the shock absorbers, vehicles
and cargo must be stronger, thus heavier, to avoid damage.
At liftoff, rockets experience a shock effect similar to driving over a
speed bump… This is when most rockets have exploded or failed.
To offset the loss of payload capacity, major programs have been initiated,
e.g., increase thrust with the Advanced Solid Rocket Motor (ASRM), or develop
exotic aluminum-lithium alloy for the External Tank. But, these measures do
not eliminate the detrimental start-up overshoot effect.
Instead of strengthening all the parts of a system, it is more effective to
use shock absorbers, isolators or other dampers. A properly designed
collapsible and locking device or material can isolate the parts of a vehicle
and the payload from the transitory effect… Expandable dampers can be used
for expendable vehicles, upper stages, and payloads. Reusable dampers, such as
dashpots, will be worth the effort of development for reusable hardware.
It is more effective to absorb the excess loads with one device than to
design all the parts to withstand the transient loads.
Transient
Conditions in Wind Tunnels
February 1994
Measuring the true maximum transient loads in every part of a system is
formidable. It requires the instrumentation of every part, which is not
practical for systems that are made up of thousands, or tens of thousands, of
parts. In the proposed work, critical parts that experience the maximum
transient effects will be identified, the actual maximum transient parameters
will be measured, and methods of extrapolation of the calculated loads for the
other parts will be established, or confirmed.
To achieve the goal, modifications to the wind tunnel, or additions, will
be required.
For example, the entry or exit of aircraft into wind shear pockets of
definite size and speed. The tests will determine the pointing accuracy of
directional systems subjected to sudden wind gusts. Other examples include the
start-up, throttle-up, throttle-down, and shut-down of pressure-activated
systems, such as, jet or rocket engines, reactors, etc.
"Here
is my 1972 Shuttle-Counter. After fuming over it, take a deep breath and
contemplate it again. The first Columbia flight in April 1981 should have been
roughly flight STS-200. The Challenger 51L in 1986, the 25th flight, should
have been STS-500. The Columbia 107 in 2003 should have been STS-1,500 (yes,
one thousand five hundred), and so on. We should have had some 2,000 Shuttle
flights by now, and not only 120-plus “problematic” flights
- - - At
65,000 lb per mission, we would have had over 100 million pounds launched into
LEO, enough hardware, fuel and provisions to do the many things that only seem
a dream today."
Back to Top
From
"Dynamic Overshoot" to "Pulsing Thrust "
In June 1986, after the official Challenger investigation was finished,
AbuTaha discovered from the Report of the Presidential Commission that a
first-order effect, known as the start-up transient “dynamic overshoot”
effect, was neglected in Shuttle design and the investigations.
The “dynamic overshoot” mistake was described to a large NASA team of
engineers behind closed-doors in October 1986. The Director of Shuttle
Engineering at the Kennedy Space Center (KSC) recommended immediate study of
the subject by AbuTaha under Purchase Order (PO) Agreement with NASA.
NASA then canceled the PO agreement. Apparently, anonymous engineers from
the Marshall Space Flight Center (MSFC) were furious that AbuTaha discussed
the liftoff loads with the KSC experts.
In response to questions from Senator John Kerry of Massachusetts about
excess forces and excess stresses in the Space Shuttle, NASA told the Senate
that it was taking those issues seriously. AbuTaha stepped aside to let the
agency deal with the “excess forces” and other issues, and he did not
write publicly about the dynamic overshoot mistake.
Three years later, AbuTaha discovered that the NASA experts did not
correctly address the “dynamic overshoot” issue, and he began to write
about it.
By 1990, AbuTaha discovered that the “dynamic overshoot” effect was not
considered in some important systems on the Hubble Space Telescope (HST), and
he took his findings to NASA, the Administration, the Congress, and the HST
office.
The initial launch of the HST was delayed for 2 weeks while AbuTaha’s
assertions were investigated. At the time, Vice President Dan Quayle, White
House Chief of Staff John Sonunu and NASA Administrator Richard Truly traveled
to the Johnson Space Center (JSC) to check out the HST situation, as described
on local DC television news.
The leaders returned from JSC in Texas. AbuTaha’s concerns were
apparently refuted. He did not hear from anyone about it. The Hubble was
launched. We almost lost the HST, a national treasure. The news concentrated
on a problem with a mirror. There were other problems with Hubble, including
solar panels, gyroscopes, and other important systems. NASA would later reveal that
“fuses” on the Hubble were changed because of the transient “dynamic
overshoot” effect.
For months, AbuTaha tried to find out what was the NASA rebuttal that
allowed the launch of the HST. He was asserting “dynamic overshoot” of 70
to 100%. NASA was asserting that “dynamic overshoot” was only 1 to 3%. The
difference between the two assertions exceeded the built-in safety margins for
the Space Shuttle. The astronauts were potentially flying with a vehicle that
had zero or negative safety margins.
AbuTaha was unyielding in his position. NASA was unyielding in its
position.
Finally, a Congressional Staff member, who attended briefings about the
JSC-HST rebuttal, told AbuTaha that NASA had shown the officials actual test
results that showed “overshoots” of 1-3%. Impossible. How could that be?
Discussing it further, the Staffer “casually” said that NASA used the most
sophisticated “pressure transducers” in their measurements. Finally, light
at the end of the long tunnel. He was talking about "force dynamic
overshoots," which are real. NASA was talking about "pressure
dynamic overshoots," which don't exist.
Paul J. Weitz, Acting Director, Johnson Space Center, confirmed the
Congressional Staffer's input. Weitz sent AbuTaha a
letter on the subject on October 13, 1992. The following letters explain how the massive difference of
opinion on the "dynamic overshoot" mistake was explained. The
start-up transient studies led AbuTaha to a novel invention, to double the
specific impulse of rockets and engines, which is also discussed in the letters.Letters
on Dynamic Overshoot and Pulsing Thrust - 1992
AbuTaha to Daniel S. Goldin, Administrator, NASA, September 21, 1992
We informed your office last month of our "pulsing-thrust"
technique for rocket engines and motors. The process provides superior
performance for space systems, and it should be of particular interest to NASA.
Paul J. Weitz, Acting Director, Johnson Space Center, to AbuTaha, October
13, 1992
"Thank you for your proposal of September 22, 1992. It has been reviewed by
technical personnel in our propulsion department. Their analysis indicates
that using a pulsing thrust technique for rocket engines and motors could
not be used for improving propulsion systems presently required by the
Johnson Space Center… Therefore, the specific impulse increase
predicted for engines using the “pulsing-thrust” technique will, in
fact, not occur. (my emphasis)
The dynamic overshoot “near-doubling” you state on page 2 of your
proposal does not occur in Space Shuttle main engine startups. Chamber
pressure is intentionally controlled to prevent overshoots greater than 2
percent above rated thrust level during the approximate 5-second Space Shuttle
main engine start transient.
"
AbuTaha's Response to Paul J. Weitz, November 23, 1992
"Your letter reveals that serious misconceptions about the overshoot effect
prevail. A clear understanding of the effect is requisite to see how to
achieve the pulsing-thrust advantage. I will give a concise description of the
confusion. I will also share this clarification with other Centers to avoid
repeating the same points.
Either the overshoot is less than 2 (two) percent, as you assert, or it is
greater than 70%, as I have stated. The difference is so enormous and
consequential that it must be resolved. The significant disparity in our
positions is the result of confusion, which I will explain.
This sentence reveals the extent of the confusion. It is correct to say
that the “thrust” overshoots at start-up, but it is absolutely incorrect
to say that the “chamber pressure” also overshoots. The pressure does not
overshoot during start-up transients. It merely fluctuates! Let me explain.
By mistakenly believing that the “chamber pressure,” which does not
overshoot, is the measure of the overshoot, your experts have mixed up the
input and the output, or the cause and the effect.
Notwithstanding that the technical personnel in your propulsion department
had dismissed my proposed pulsing-thrust advantage, I am available to give the
specific details of the technique in a NASA sponsored Seminar, or Colloquium."
AbuTaha to Aaron Cohen, Acting Deputy Administrator, NASA, November 23,
1992
...The enclosed letter to Mr. Paul J. Weitz at JSC explains the serious
mix-up by the other experts, as best as I can describe it... then, perhaps, my
persistence, and not the irritation, will be remembered.
Reference to the pulsing-thrust technique, which I brought to your
attention before, some experts have already dismissed the process before even
seeing the detailed analysis and specific steps required to achieve the
proposed thrust advantage...
AbuTaha to R. J. Lee, Director, MSFC, NASA, November 23, 1992
Thank you for your kind letter of September 24, 1992. Due to
personal circumstances, I have not been able to prepare a detailed unsolicited
proposal on the pulsing-thrust technique. My patent application requires
considerable amendments, which when completed will show the applicability of
the method to a variety of systems, in addition to rocket engines and
motors.
AbuTaha to Pierre J. Madon, Vice President E&R, INTELSAT, November 9,
1992
...The first equation in your mathematical analysis clearly shows the
dynamic overshoot doubled-response. The advantage is there, and the question
is how to harness it.
As to my shuttle-related study, the Institution of Mechanical Engineers in
the UK had reviewed my 1992 paper and described it as "an excellent piece
of work with far-reaching consequences." There have been other favorable
reviews by other competent experts... As a citizen of the United States, I
take exception to your criticism of my conduct in that case. Strictly, out of
consideration to NASA and to the (U.S.) national security, I had shared the
specifics of my results ONLY with NASA in 1986 in closed-door meetings. I
might add that the near-doubling dynamic-overshoot effect was also overlooked
in the design of other systems, including the INTELSAT systems. The dynamic
overshoot effect is generally not even discussed in engineering textbooks on
spacecraft design and propulsion.
[Note: "Pulsing Thrust" is AbuTaha's Invention to double the
thrust of rocket engines and motors. Several leaders in the aerospace industry
expressed interest in the Invention, e.g., a Rocketdyne executive told
AbuTaha, "If it is what you say, we're interested," and
Norman Augustine, then Chairman of Martin Marietta, referred the Invention to
top engineering officers at the Company for evaluation. But, the
senior engineers from NASA, the aerospace industry, aerospace professional organizations and universities dismissed AbuTaha's
invention out of hand. Some senior engineers went as far as to submit to
AbuTaha mathematical analysis to show that the Invention was impossible.
Today, in 2009, "doubling the thrust" Invention is a reality and
there are hundreds of technical papers about it on the Internet. The Weitz'
above letter was one of the few polite dismissals of the Invention [See
"Pulsing Thrust" webpage for more details].
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