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December 24 2011
I cannot believe that it possible a woman can become Premier of US and A
– in Kazakhstan, we say that to give a woman power, is like to give a
monkey a gun – very dangerous. We do not give monkeys guns any more in
Kazakhstan ever since the Astana Zoo massacre of 2003 when Torkin the
orang-utan shoot 17 schoolchildrens. I personal would like the
basketball player, Barak Obamas to be Premier.
Борат Сагдиев
Борат Сагдиев
March 16 2011
Anmerkungen von Richard Feynman zum Untersuchungsbericht des Challenger Unglückes - von mir gekürzt um das Shuttlespezifische Zeug. Der Rest gilt auch für sowjetische, japanische und deutsche AKWs.
Appendix F - Personal observations on the reliability of the Shuttle
by R. P. Feynman
Introduction
It appears that there are enormous differences of opinion as to the probability of a failure with loss of vehicle and of human life. The estimates range from roughly 1 in 100 to 1 in 100,000. The higher figures come from the working engineers, and the very low figures from management. What are the causes and consequences of this lack of agreement? Since 1 part in 100,000 would imply that one could put a Shuttle up each day for 300 years expecting to lose only one, we could properly ask "What is the cause of management's fantastic faith in the machinery?"
We have also found that certification criteria used in Flight Readiness Reviews often develop a gradually decreasing strictness. The argument that the same risk was flown before without failure is often accepted as an argument for the safety of accepting it again. Because of this, obvious weaknesses are accepted again and again, sometimes without a sufficiently serious attempt to remedy them, or to delay a flight because of their continued presence.
[...]
Solid Rockets (SRB)
An estimate of the reliability of solid rockets was made by the range safety officer, by studying the experience of all previous rocket flights. Out of a total of nearly 2,900 flights, 121 failed (1 in 25). This includes, however, what may be called, early errors, rockets flown for the first few times in which design errors are discovered and fixed. A more reasonable figure for the mature rockets might be 1 in 50. With special care in the selection of parts and in inspection, a figure of below 1 in 100 might be achieved but 1 in 1,000 is probably not attainable with today's technology. (Since there are two rockets on the Shuttle, these rocket failure rates must be doubled to get Shuttle failure rates from Solid Rocket Booster failure.)
NASA officials argue that the figure is much lower. They point out that these figures are for unmanned rockets but since the Shuttle is a manned vehicle "the probability of mission success is necessarily very close to 1.0." It is not very clear what this phrase means. Does it mean it is close to 1 or that it ought to be close to 1? They go on to explain "Historically this extremely high degree of mission success has given rise to a difference in philosophy between manned space flight programs and unmanned programs; i.e., numerical probability usage versus engineering judgment." (These quotations are from "Space Shuttle Data for Planetary Mission RTG Safety Analysis," Pages 3-1, 3-1, February 15, 1985, NASA, JSC.) It is true that if the probability of failure was as low as 1 in 100,000 it would take an inordinate number of tests to determine it ( you would get nothing but a string of perfect flights from which no precise figure, other than that the probability is likely less than the number of such flights in the string so far). But, if the real probability is not so small, flights would show troubles, near failures, and possible actual failures with a reasonable number of trials. and standard statistical methods could give a reasonable estimate. In fact, previous NASA experience had shown, on occasion, just such difficulties, near accidents, and accidents, all giving warning that the probability of flight failure was not so very small. The inconsistency of the argument not to determine reliability through historical experience, as the range safety officer did, is that NASA also appeals to history, beginning "Historically this high degree of mission success..."
Finally, if we are to replace standard numerical probability usage with engineering judgment, why do we find such an enormous disparity between the management estimate and the judgment of the engineers? It would appear that, for whatever purpose, be it for internal or external consumption, the management of NASA exaggerates the reliability of its product, to the point of fantasy.
The history of the certification and Flight Readiness Reviews will not be repeated here. (See other part of Commission reports.) The phenomenon of accepting for flight, seals that had shown erosion and blow-by in previous flights, is very clear. The Challenger flight is an excellent example. There are several references to flights that had gone before. The acceptance and success of these flights is taken as evidence of safety. But erosion and blow-by are not what the design expected. They are warnings that something is wrong. The equipment is not operating as expected, and therefore there is a danger that it can operate with even wider deviations in this unexpected and not thoroughly understood way. The fact that this danger did not lead to a catastrophe before is no guarantee that it will not the next time, unless it is completely understood. When playing Russian roulette the fact that the first shot got off safely is little comfort for the next.
[...]
Instead of being very concerned that variations of poorly understood conditions might reasonably create a deeper erosion this time, it was asserted, there was "a safety factor of three." This is a strange use of the engineer's term ,"safety factor." If a bridge is built to withstand a certain load without the beams permanently deforming, cracking, or breaking, it may be designed for the materials used to actually stand up under three times the load. This "safety factor" is to allow for uncertain excesses of load, or unknown extra loads, or weaknesses in the material that might have unexpected flaws, etc. If now the expected load comes on to the new bridge and a crack appears in a beam, this is a failure of the design. There was no safety factor at all; even though the bridge did not actually collapse because the crack went only one-third of the way through the beam.
[...]
The usual way that such engines are designed (for military or civilian aircraft) may be called the component system, or bottom-up design. First it is necessary to thoroughly understand the properties and limitations of the materials to be used (for turbine blades, for example), and tests are begun in experimental rigs to determine those. With this knowledge larger component parts (such as bearings) are designed and tested individually. As deficiencies and design errors are noted they are corrected and verified with further testing. Since one tests only parts at a time these tests and modifications are not overly expensive. Finally one works up to the final design of the entire engine, to the necessary specifications. There is a good chance, by this time that the engine will generally succeed, or that any failures are easily isolated and analyzed because the failure modes, limitations of materials, etc., are so well understood. There is a very good chance that the modifications to the engine to get around the final difficulties are not very hard to make, for most of the serious problems have already been discovered and dealt with in the earlier, less expensive, stages of the process.
[...]
To summarize then, the computer software checking system and attitude is of the highest quality. There appears to be no process of gradually fooling oneself while degrading standards so characteristic of the Solid Rocket Booster or Space Shuttle Main Engine safety systems. To be sure, there have been recent suggestions by management to curtail such elaborate and expensive tests as being unnecessary at this late date in Shuttle history. This must be resisted for it does not appreciate the mutual subtle influences, and sources of error generated by even small changes of one part of a program on another. There are perpetual requests for changes as new payloads and new demands and modifications are suggested by the users. Changes are expensive because they require extensive testing. The proper way to save money is to curtail the number of requested changes, not the quality of testing for each.
[...]
Conclusions
If a reasonable launch schedule is to be maintained, engineering often cannot be done fast enough to keep up with the expectations of originally conservative certification criteria designed to guarantee a very safe vehicle. In these situations, subtly, and often with apparently logical arguments, the criteria are altered so that flights may still be certified in time. They therefore fly in a relatively unsafe condition, with a chance of failure of the order of a percent (it is difficult to be more accurate).
Official management, on the other hand, claims to believe the probability of failure is a thousand times less. One reason for this may be an attempt to assure the government of NASA perfection and success in order to ensure the supply of funds. The other may be that they sincerely believed it to be true, demonstrating an almost incredible lack of communication between themselves and their working engineers.
In any event this has had very unfortunate consequences, the most serious of which is to encourage ordinary citizens to fly in such a dangerous machine, as if it had attained the safety of an ordinary airliner. The astronauts, like test pilots, should know their risks, and we honor them for their courage. Who can doubt that McAuliffe was equally a person of great courage, who was closer to an awareness of the true risk than NASA management would have us believe?
Let us make recommendations to ensure that NASA officials deal in a world of reality in understanding technological weaknesses and imperfections well enough to be actively trying to eliminate them. They must live in reality in comparing the costs and utility of the Shuttle to other methods of entering space. And they must be realistic in making contracts, in estimating costs, and the difficulty of the projects. Only realistic flight schedules should be proposed, schedules that have a reasonable chance of being met. If in this way the government would not support them, then so be it. NASA owes it to the citizens from whom it asks support to be frank, honest, and informative, so that these citizens can make the wisest decisions for the use of their limited resources.
For a successful technology, reality must take precedence over public relations, for nature cannot be fooled.
Appendix F - Personal observations on the reliability of the Shuttle
by R. P. Feynman
Introduction
It appears that there are enormous differences of opinion as to the probability of a failure with loss of vehicle and of human life. The estimates range from roughly 1 in 100 to 1 in 100,000. The higher figures come from the working engineers, and the very low figures from management. What are the causes and consequences of this lack of agreement? Since 1 part in 100,000 would imply that one could put a Shuttle up each day for 300 years expecting to lose only one, we could properly ask "What is the cause of management's fantastic faith in the machinery?"
We have also found that certification criteria used in Flight Readiness Reviews often develop a gradually decreasing strictness. The argument that the same risk was flown before without failure is often accepted as an argument for the safety of accepting it again. Because of this, obvious weaknesses are accepted again and again, sometimes without a sufficiently serious attempt to remedy them, or to delay a flight because of their continued presence.
[...]
Solid Rockets (SRB)
An estimate of the reliability of solid rockets was made by the range safety officer, by studying the experience of all previous rocket flights. Out of a total of nearly 2,900 flights, 121 failed (1 in 25). This includes, however, what may be called, early errors, rockets flown for the first few times in which design errors are discovered and fixed. A more reasonable figure for the mature rockets might be 1 in 50. With special care in the selection of parts and in inspection, a figure of below 1 in 100 might be achieved but 1 in 1,000 is probably not attainable with today's technology. (Since there are two rockets on the Shuttle, these rocket failure rates must be doubled to get Shuttle failure rates from Solid Rocket Booster failure.)
NASA officials argue that the figure is much lower. They point out that these figures are for unmanned rockets but since the Shuttle is a manned vehicle "the probability of mission success is necessarily very close to 1.0." It is not very clear what this phrase means. Does it mean it is close to 1 or that it ought to be close to 1? They go on to explain "Historically this extremely high degree of mission success has given rise to a difference in philosophy between manned space flight programs and unmanned programs; i.e., numerical probability usage versus engineering judgment." (These quotations are from "Space Shuttle Data for Planetary Mission RTG Safety Analysis," Pages 3-1, 3-1, February 15, 1985, NASA, JSC.) It is true that if the probability of failure was as low as 1 in 100,000 it would take an inordinate number of tests to determine it ( you would get nothing but a string of perfect flights from which no precise figure, other than that the probability is likely less than the number of such flights in the string so far). But, if the real probability is not so small, flights would show troubles, near failures, and possible actual failures with a reasonable number of trials. and standard statistical methods could give a reasonable estimate. In fact, previous NASA experience had shown, on occasion, just such difficulties, near accidents, and accidents, all giving warning that the probability of flight failure was not so very small. The inconsistency of the argument not to determine reliability through historical experience, as the range safety officer did, is that NASA also appeals to history, beginning "Historically this high degree of mission success..."
Finally, if we are to replace standard numerical probability usage with engineering judgment, why do we find such an enormous disparity between the management estimate and the judgment of the engineers? It would appear that, for whatever purpose, be it for internal or external consumption, the management of NASA exaggerates the reliability of its product, to the point of fantasy.
The history of the certification and Flight Readiness Reviews will not be repeated here. (See other part of Commission reports.) The phenomenon of accepting for flight, seals that had shown erosion and blow-by in previous flights, is very clear. The Challenger flight is an excellent example. There are several references to flights that had gone before. The acceptance and success of these flights is taken as evidence of safety. But erosion and blow-by are not what the design expected. They are warnings that something is wrong. The equipment is not operating as expected, and therefore there is a danger that it can operate with even wider deviations in this unexpected and not thoroughly understood way. The fact that this danger did not lead to a catastrophe before is no guarantee that it will not the next time, unless it is completely understood. When playing Russian roulette the fact that the first shot got off safely is little comfort for the next.
[...]
Instead of being very concerned that variations of poorly understood conditions might reasonably create a deeper erosion this time, it was asserted, there was "a safety factor of three." This is a strange use of the engineer's term ,"safety factor." If a bridge is built to withstand a certain load without the beams permanently deforming, cracking, or breaking, it may be designed for the materials used to actually stand up under three times the load. This "safety factor" is to allow for uncertain excesses of load, or unknown extra loads, or weaknesses in the material that might have unexpected flaws, etc. If now the expected load comes on to the new bridge and a crack appears in a beam, this is a failure of the design. There was no safety factor at all; even though the bridge did not actually collapse because the crack went only one-third of the way through the beam.
[...]
The usual way that such engines are designed (for military or civilian aircraft) may be called the component system, or bottom-up design. First it is necessary to thoroughly understand the properties and limitations of the materials to be used (for turbine blades, for example), and tests are begun in experimental rigs to determine those. With this knowledge larger component parts (such as bearings) are designed and tested individually. As deficiencies and design errors are noted they are corrected and verified with further testing. Since one tests only parts at a time these tests and modifications are not overly expensive. Finally one works up to the final design of the entire engine, to the necessary specifications. There is a good chance, by this time that the engine will generally succeed, or that any failures are easily isolated and analyzed because the failure modes, limitations of materials, etc., are so well understood. There is a very good chance that the modifications to the engine to get around the final difficulties are not very hard to make, for most of the serious problems have already been discovered and dealt with in the earlier, less expensive, stages of the process.
[...]
To summarize then, the computer software checking system and attitude is of the highest quality. There appears to be no process of gradually fooling oneself while degrading standards so characteristic of the Solid Rocket Booster or Space Shuttle Main Engine safety systems. To be sure, there have been recent suggestions by management to curtail such elaborate and expensive tests as being unnecessary at this late date in Shuttle history. This must be resisted for it does not appreciate the mutual subtle influences, and sources of error generated by even small changes of one part of a program on another. There are perpetual requests for changes as new payloads and new demands and modifications are suggested by the users. Changes are expensive because they require extensive testing. The proper way to save money is to curtail the number of requested changes, not the quality of testing for each.
[...]
Conclusions
If a reasonable launch schedule is to be maintained, engineering often cannot be done fast enough to keep up with the expectations of originally conservative certification criteria designed to guarantee a very safe vehicle. In these situations, subtly, and often with apparently logical arguments, the criteria are altered so that flights may still be certified in time. They therefore fly in a relatively unsafe condition, with a chance of failure of the order of a percent (it is difficult to be more accurate).
Official management, on the other hand, claims to believe the probability of failure is a thousand times less. One reason for this may be an attempt to assure the government of NASA perfection and success in order to ensure the supply of funds. The other may be that they sincerely believed it to be true, demonstrating an almost incredible lack of communication between themselves and their working engineers.
In any event this has had very unfortunate consequences, the most serious of which is to encourage ordinary citizens to fly in such a dangerous machine, as if it had attained the safety of an ordinary airliner. The astronauts, like test pilots, should know their risks, and we honor them for their courage. Who can doubt that McAuliffe was equally a person of great courage, who was closer to an awareness of the true risk than NASA management would have us believe?
Let us make recommendations to ensure that NASA officials deal in a world of reality in understanding technological weaknesses and imperfections well enough to be actively trying to eliminate them. They must live in reality in comparing the costs and utility of the Shuttle to other methods of entering space. And they must be realistic in making contracts, in estimating costs, and the difficulty of the projects. Only realistic flight schedules should be proposed, schedules that have a reasonable chance of being met. If in this way the government would not support them, then so be it. NASA owes it to the citizens from whom it asks support to be frank, honest, and informative, so that these citizens can make the wisest decisions for the use of their limited resources.
For a successful technology, reality must take precedence over public relations, for nature cannot be fooled.
Reposted by
roweb
roweb
December 15 2010
Der Anon, der war kerngesund,
Ein dicker Bub und kugelrund.
Er hatte Backen rot und frisch;
Die Suppe aß er hübsch bei Tisch.
Doch einmal fing er an zu schrein:
"Ich esse keine Suppe! Nein!
Ich esse meine Suppe nicht!
Nein, meine Suppe ess ich nicht!"
Ein dicker Bub und kugelrund.
Er hatte Backen rot und frisch;
Die Suppe aß er hübsch bei Tisch.
Doch einmal fing er an zu schrein:
"Ich esse keine Suppe! Nein!
Ich esse meine Suppe nicht!
Nein, meine Suppe ess ich nicht!"
Reposted by
legba7
legba7
December 11 2010
“ <<69936>> 6/30/2006 13:30 06MUNICH397 Consulate Munich UNCLASSIFIED
VZCZCXRO6095 PP RUEHAG RUEHDF RUEHLZ DE RUEHMZ #0397/01 1811330 ZNR UUUUU ZZH P 301330Z JUN 06 FM AMCONSUL MUNICH TO RUEHC/SECSTATE WASHDC PRIORITY 3318 INFO RUCNFRG/FRG COLLECTIVE TAGS: PGOV, SENV, GM SUBJECT: BRUNO'S LAST STAND -- FIRST WILD BEAR IN 170 YEARS
Unclas section 01 of 02 munich 000397
Sipdis
Sipdis
E.o. 12958: n/a Tags: pgov, senv, gm Subject: bruno's last stand -- first wild bear in 170 years proves too wild for bavaria
------- summary -------
1. Despite all the attention surrounding the World Cup, EADS' woes and health care reform, Bavarians and many Germans have been transfixed by a two-year-old brown bear named "Bruno" that wandered across international borders into Bavaria, a government minister's agenda, a hunter's crosshairs, and the hearts of millions. Following Bruno's government-sanctioned shooting, questions remain over the political fallout and the future of wild bears in the German Alps. The incident also offers a snippet of insight into German attitudes toward the environment. End Summary.
----------------------- a visitor named "bruno" -----------------------
2. The bear, dubbed "Bruno" by the media, began his journey in Italy, where he was released as part of a program to reintroduce brown bears from Slovenia in the Alps. After wandering across the border from Austria, he was first sighted in Bavaria on May 20. As the first wild bear seen in Germany since 1835, Bruno was initially extended a warm public welcome by Bavarian Environment Minister Werner Schnappauf -- after all, Bruno could prove a boon for Bavaria's image just as visitors from around the world arrived for the World Cup.
------------------ the "problem bear" ------------------
3. However, as Bavarian Interior Minister Beckstein has often emphasized, foreigners are only welcome in Bavaria provided they are willing to adapt to German culture and traditions. Bruno quickly wore out his welcome by raiding stables, killing sheep, chickens, and a child's pet rabbit. The Bavarian government declared Bruno "Ursus non Grata" and ordered that he be shot or captured. Vexed by Bruno's unchecked roaming across Bavaria -- he was even seen sitting on the steps of a police station eating a guinea pig -- Minister-President Edmund Stoiber took to referring to him as "the Problem Bear."
4. Nevertheless, Bruno appeared to win the battle for the hearts and minds of the public -- Schnappauf received some 1,300 letters and drawings from children all over Germany appealing for Bruno to be kept alive. Following criticism of the edict that Bruno be shot, Schnappauf gave the animal a stay of execution and, at a cost of over Euro 125,000, flew in a special trap from Colorado and a team of Finnish bear hunters with specially trained dogs. After the Finnish hunters failed at their task, Schnappauf reinstated the shoot-to-kill order effective June 26. Early in the morning of that same day, Bruno met his demise at the hands of an (as yet) unnamed hunter. Bruno, stuffed, is to be put on display at a natural history museum in Munich's Nymphenburg Palace.
----------------------------------- "may his ursine soul rest in peace" -----------------------------------
5. Almost immediately, criticism of the Bavarian government started pouring in from across Bavaria and the world. Minister Schnappauf has received multiple death threats and calls for his resignation. State prosecutors have received nine legal complaints, several against Schnappauf, for alleged breaches of hunting and animal protection laws. Death threats have also been made against the hunter. Schnappauf has defended himself by saying that had Bruno attacked a human, calls for his resignation would be better justified. Future bears, he said, would be welcome in Bavaria, provided they behaved appropriately.
6. The "Bruno" saga has received a disproportional share of press play, including in the international media. The Munich tabloid "TZ," which has devoted no less than eleven cover pages to Bruno since May 21, published an obituary threatening revenge at the voting booth for Bruno's death, and called on people to send protest letters and e-mails to Minister-President Stoiber and Minister Schnappauf. Germany's major tabloid "Bild" even suggested a state funeral for Bruno might be appropriate. "Spiegel Online's" daily updated "Bruno Watch" included an obituary entitled "A Problem Bear or Bavaria's Problem?" and compared Bruno's death with that of Elvis, Marilyn Monroe, Jimi Hendrix, John Lennon, and Princess Diana. Mirroring the sentiment of the general public, the piece concluded: "For indeed Bruno was murdered, shot down in the prime of his young life, executed
Munich 00000397 002 of 002
in cold blood. We should reflect now on whether we feel happy with what we have done. We share a collective guilt for Bruno's demise, our inability to co-exist with nature has yet again prompted us to reach for the trigger. Bruno is dead and we are all the poorer for it: May his ursine soul rest in peace."
------- comment -------
7. Bruno has been the media's June flavor of the month. While the attention lavished on Bruno has taken nearly everyone by surprise, we expect the criticism leveled at Schnappauf and Stoiber to be relatively fleeting -- radical animal rights advocates who make death threats aren't generally considered the CSU's base anyway. Perhaps the greatest insight from the whole Bruno affair might be that despite the veneer of "greenness" extolled by German society, modern Germany in fact coexists uneasily with untamed nature. The contrast between the massive hunt for the first wild bear seen in Bavaria in over 170 years and the recent story of a clawless housecat treeing a bear in New Jersey couldn't be much more stark. True wilderness, even in mountainous Bavaria, hasn't really existed in Germany for generations -- nature is good, as long as it is controlled, channeled, and subdued. If the saga of Bavaria's "Problem Bear" is any indicator, the strategy of reintroducing wild bears to the Alps, at least the German Alps, may be doomed to failure -- that is, unless the bears are willing to cooperate by not being too wild.
8. This report has been coordinated with Embassy Berlin.
9. Previous reporting from Munich is available on our SIPRNET website at www.state.sgov.gov/p/eur/munich/ .
Rooney ”
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