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Tuesday, September 29, 2009

Reading List: Truth, Lies, and O-Rings

McDonald, Allan J. and James R. Hansen. Truth, Lies, and O-Rings. Gainesville, FL: University Press of Florida, 2009. ISBN 978-0-8130-3326-6.
More than two decades have elapsed since Space Shuttle Challenger met its tragic end on that cold Florida morning in January 1986, and a shelf-full of books have been written about the accident and its aftermath, ranging from the five volume official report of the Presidential commission convened to investigate the disaster to conspiracy theories and accounts of religious experiences. Is it possible, at this remove, to say anything new about Challenger? The answer is unequivocally yes, as this book conclusively demonstrates.

The night before Challenger was launched on its last mission, Allan McDonald attended the final day before launch flight readiness review at the Kennedy Space Center, representing Morton Thiokol, manufacturer of the solid rocket motors, where he was Director of the Space Shuttle Solid Rocket Motor Project. McDonald initially presented Thiokol's judgement that the launch should be postponed because the temperatures forecast for launch day were far below the experience base of the shuttle program and an earlier flight at the lowest temperature to date had shown evidence of blow-by the O-ring seals in the solid rocket field joints. Thiokol engineers were concerned that low temperatures would reduce the resiliency of the elastomeric rings, causing them to fail to seal during the critical ignition transient. McDonald was astonished when NASA personnel, in a reversal of their usual rôle of challenging contractors to prove why their hardware was safe to fly, demanded that Thiokol prove the solid motor was unsafe in order to scrub the launch. Thiokol management requested a five minute offline caucus back at the plant in Utah (in which McDonald did not participate) which stretched to thirty minutes and ended up with a recommendation to launch. NASA took the unprecedented step of requiring a written approval to launch from Thiokol, which McDonald refused to provide, but which was supplied by his boss in Utah.

After the loss of the shuttle and its crew, and the discovery shortly thereafter that the proximate cause was almost certainly a leak in the aft field joint of the right solid rocket booster, NASA and Thiokol appeared to circle the wagons, trying to deflect responsibility from themselves and obscure the information available to decision makers in a position to stop the launch. It was not until McDonald's testimony to the Presidential Commission chaired by former Secretary of State William P. Rogers that the truth began to come out. This thrust McDonald, up to then an obscure engineering manager, into the media spotlight and the political arena, which he quickly discovered was not at all about his priorities as an engineer: finding out what went wrong and fixing it so it could never happen again.

This memoir, composed by McDonald from contemporary notes and documents with the aid of space historian James R. Hansen (author of the bestselling authorised biography of Neil Armstrong) takes the reader through the catastrophe and its aftermath, as seen by an insider who was there at the decision to launch, on a console in the firing room when disaster struck, before the closed and public sessions of the Presidential commission, pursued by sensation-hungry media, testifying before congressional committees, and consumed by the redesign and certification effort and the push to return the shuttle to flight. It is a personal story, but told in terms, as engineers are wont to do, based in the facts of the hardware, the experimental evidence, and the recollection of meetings which made the key decisions before and after the tragedy.

Anybody whose career may eventually land them, intentionally or not (the latter almost always the case), in the public arena can profit from reading this book. Even if you know nothing about and have no interest in solid rocket motors, O-rings, space exploration, or NASA, the dynamics of a sincere, dedicated engineer who was bent on doing the right thing encountering the ravenous media and preening politicians is a cautionary tale for anybody who finds themselves in a similar position. I wish I'd had the opportunity to read this book before my own Dark Night of the Soul encounter with a reporter from the legacy media. I do not mean to equate my own mild experience with the Hell that McDonald experienced—just to say that his narrative would have been a bracing preparation for what was to come.

The chapters on the Rogers Commission investigation provided, for me, a perspective I'd not previously encountered. Many people think of William P. Rogers primarily as Nixon's first Secretary of State who was upstaged and eventually replaced by Henry Kissinger. But before that Rogers was a federal prosecutor going after organised crime in New York City and then was Attorney General in the Eisenhower administration from 1957 to 1961. Rogers may have aged, but his skills as an interrogator and cross-examiner never weakened. In the sworn testimony quoted here, NASA managers, who come across like the kids who were the smartest in their high school class and then find themselves on the left side of the bell curve when they show up as freshmen at MIT, are pinned like specimen bugs to their own viewgraphs when they try to spin Rogers and his tag team of technical takedown artists including Richard Feynman, Neil Armstrong, and Sally Ride.

One thing which is never discussed here, but should be, is just how totally insane it is to use large solid rockets, in any form, in a human spaceflight program. Understand: solid rockets are best thought of as “directed bombs”, but if detonated at an inopportune time, or when not in launch configuration, can cause catastrophe. A simple spark of static electricity can suffice to ignite the propellant in a solid rocket, and once ignited there is no way to extinguish it until it is entirely consumed. Consider: in the Shuttle era, there are usually one or more Shuttle stacks in the Vehicle Assembly Building (VAB), and if NASA's Constellation Program continues, this building will continue to stack solid rocket motors in decades to come. Sooner or later, the inevitable is going to happen: a static spark, a crane dropping a segment, or an interference fit of two segments sending a hot fragment into the propellant below. The consequence: destruction of the VAB, all hardware inside, and the death of all people working therein. The expected stand-down of the U.S. human spaceflight program after such an event is on the order of a decade. Am I exaggerating the risks here? Well, maybe; you decide. But within two years, three separate disasters struck the production of large solid motors in 1985–1986. I shall predict: if NASA continue to use large solid motors in their human spaceflight program, there will be a decade-long gap in U.S. human spaceflight sometime in the next twenty years.

If you're sufficiently interested in these arcane matters to have read this far, you should read this book. Based upon notes, it's a bit repetitive, as many of the same matters were discussed in the various venues in which McDonald testified. But if you want to read a single book to prepare you for being unexpectedly thrust into the maw of ravenous media and politicians, I know of none better.

Posted at 23:57 Permalink

Thursday, September 24, 2009

Reading List: Executive Power

Flynn, Vince. Executive Power. New York: Pocket Books, 2003. ISBN 978-0-7434-5396-7.
This is the fourth novel in the Mitch Rapp (warning—the article at this link contains minor spoilers) series. At the end of the third novel, Separation of Power (August 2009), Rapp's identity was outed by a self-righteous and opportunistic congressman (who gets what's coming to him), and soon-to-be-married Rapp prepares to settle down at a desk job in the CIA's counterterrorism centre. But it's hard to keep a man of action down, and when political perfidy blows the cover on a hostage rescue operation in the Philippines, resulting in the death of two Navy SEALs, Rapp gets involved in the follow-up reprisal operation in a much more direct manner than anybody expected, and winds up with a non-life-threatening but extremely embarrassing and difficult to explain injury (hint, he spends most of the balance of the book standing up). Rapp has no hesitation in taking on terror masters single-handed, but he finds himself utterly unprepared for the withering scorn unleashed against him by the two women in his life: bride and boss.

Rapp soon finds himself on the trail of a person much like himself: an assassin who works in the shadows and leaves almost no traces of evidence. This malefactor, motivated by the desire for a political outcome just as sincere as Rapp's wish to protect his nation, is manipulating (or being manipulated by?) a rogue Saudi billionaire bent on provoking mayhem in the Middle East. The ever meddlesome chief of the Mossad is swept into the scheme, and events spiral toward the brink as Rapp tries to figure out what is really going on. The conclusion gets Rapp involved up close and personal, the way he likes it, and comes to a satisfying end.

This is the first of the Mitch Rapp novels to be written after the terrorist attacks of September 2001. Other than a few oblique references to those events, little in the worldview of the series has changed. Flynn's attention to detail continues to shine in this story. About the only unrealistic thing is imagining the U.S. government as actually being serious and competent in taking the battle to terrorists. See my comments on the first installment for additional details about the series and a link to an interview with the author.

Posted at 15:02 Permalink

When Zucchini Go Unobserved


Update: By popular request, the vital statistics are as follows: length from tip to tip along the curve, 58 cm; circumference at the widest cutting plane, 28 cm; mass, 1.4 kg. (2009-09-28 18:22 UTC)

Posted at 01:16 Permalink

Sunday, September 13, 2009

Your Glass Can Fail


Click image to enlarge.

As reality-hardened™ engineers know, no matter how many years you've trod this Earth, there's always something new to go wrong when you least expect it. A few days ago, I went to refill my glass of programming fluid with sugar-free lemonade. The propellant transfer operation was nominal, but when I raised the glass to my lips to imbibe the refreshing beverage, the bottom of the glass separated, jettisoning its entire contents in a messy libation to the Floor God. Apparently, thanks to hundreds of temperature cycles in the Fourmilab dishgrinder, a hairline crack had propagated all around the base of the glass, and the shock of being filled with chilly swill sufficed to advance the fracture all the way through.

I cleaned up the mess, washed the failed glass, and took the picture above. Remember, however confident you may be of the absence of slips twixt cup and lip, your glass can fail.

And, yes, the title of this post is an oblique reference to Larry Niven's 1967 story, “Safe at Any Speed”.

Posted at 00:09 Permalink

Thursday, September 10, 2009

Respectfulness vs. Civility

It's become almost a cliché that, when urging citizens to express their disagreement and/or displeasure with their elected representatives, they're enjoined to “be respectful”.

Why, precisely?

It's one thing to be civil—to discuss policy differences, not personalities, to avoid shouting, chanting of slogans, profanity, and allow the politician to reply without interruption. That's just how civilised people treat one another in public fora (and why it's called “civility”). But respect, and respectfulness is something else entirely. People are respectful to those who have earned their respect through their actions. There is no obligation to respect a politician simply because he or she persuaded more people to vote for them than the other guy. If they're spending money irresponsibly, running up huge debts to be paid off by generations yet unborn, debasing the currency, taxing the vitality out of the economy, and acting in the interests of the lobbyists who fund their campaigns instead of their constituents, they deserve no respect, and citizens should feel no reason to “be respectful” in their presence.

Look at it this way: would you feel respectful of a CEO whose company sold you a defective product, just because he had been chosen by a board of directors elected by the shareholders of the company and is handsomely paid for his services? Of course not! His company just picked your pocket, and as head of the company, you have no reason to respect him. But the greatest pocket-pickers and purveyors of shoddy service are politicians, and they are owed respectfulness only if they have demonstrated, by their actions in office, that they are deserving of respect.

Similarly, politicians like to be formally addressed as “The Honourable”. Fie on that. Citizens should only call them “Honourable” if they are actually, you know, honourable.

Posted at 21:09 Permalink

Tuesday, September 8, 2009

Two stage tomato


From Fourmifarm.

Posted at 02:24 Permalink

Sunday, September 6, 2009

Reading List: Feux follets et champignons nucléaires

Charpak, Georges et Richard L. Garwin. Feux follets et champignons nucléaires. Paris: Odile Jacob, [1997] 2000. ISBN 978-2-7381-0857-9.
Georges Charpak won the Nobel Prize in Physics in 1992, and was the last person, as of this writing, to have won an unshared Physics Nobel. Richard Garwin is a quintessential “defence intellectual”: he studied under Fermi, did the detailed design of Ivy Mike, the first thermonuclear bomb, has been a member of Jason and adviser on issues of nuclear arms control and disarmament for decades, and has been a passionate advocate against ballistic missile defence and for reducing the number of nuclear warheads and the state of alert of strategic nuclear forces.

In this book the authors, who do not agree on everything and take the liberty to break out from the main text on several occasions to present their individual viewpoints, assess the state of nuclear energy—civil and military—at the turn of the century and try to chart a reasonable path into the future which is consistent with the aspirations of people in developing countries, the needs of a burgeoning population, and the necessity of protecting the environment both from potential risks from nuclear technology but also the consequences of not employing it as a source of energy. (Even taking Chernobyl into account, the total radiation emitted by coal-fired power plants is far greater than that of all nuclear stations combined: coal contains thorium, and when it is burned, it escapes in flue gases or is captured and disposed of in landfills. And that's not even mentioning the carbon dioxide emitted by burning fossil fuels.)

The reader of this book will learn a great deal about the details of nuclear energy: perhaps more than some will have the patience to endure. I made it through, and now I really understand, for the first time, why light water reactors have a negative thermal coefficient: as the core gets hotter, the U-238 atoms are increasingly agitated by the heat, and consequently are more likely due to Doppler shift to fall into one of the resonances where their neutron absorption is dramatically enhanced.

Charpak and Garwin are in complete agreement that civil nuclear power should be the primary source of new electrical generation capacity until and unless something better (such as fusion) comes along. They differ strongly on the issue of fuel cycle and waste management: Charpak argues for the French approach of reprocessing spent fuel, extracting the bred plutonium, and burning it in power reactors in the form of mixed oxide (MOX) fuel. Garwin argues for the U.S. approach of a once-through fuel cycle, with used fuel buried, its plutonium energy content discarded in the interest of “economy”. Charpak points out that the French approach drastically reduces the volume of nuclear waste to be buried, and observes that France does not have a Nevada in which to bury it.

Both authors concur that breeder reactors will eventually have a rôle to play in nuclear power generation. Not only do breeders multiply the energy which can be recovered from natural uranium by a factor of fifty, they can be used to “burn up” many of the radioactive waste products of conventional light water reactors. Several next-generation reactor concepts are discussed, including Carlo Rubbia's energy amplifier, in which the core is inherently subcritical, and designs for more conventional reactors which are inherently safe in the event of loss of control feedback or cooling. They conclude, however, that further technology maturation is required before breeders enter into full production use and that, in retrospect, Superphénix was premature.

The last third of the book is devoted to nuclear weapons and the prospects for reducing the inventory of declared nuclear powers, increasing stability, and preventing proliferation. There is, as you would expect from Garwin, a great deal of bashing the concept of ballistic missile defence (“It can't possibly work, and if it did it would be bad”). This is quite dated, as many of the arguments and the lengthy reprinted article date from the mid 1980s when the threat was a massive “war-gasm” salvo launch of thousands of ICBMs from the Soviet Union, not one or two missiles from a rogue despot who's feeling “ronery”. The authors quite reasonably argue that current nuclear force levels are absurd, and that an arsenal about the size of France's (on the order of 500 warheads) should suffice for any conceivable deterrent purpose. They dance around the option of eliminating nuclear arms entirely, and conclude that such a goal is probably unachievable in a world in which such a posture would create an incentive for a rogue state to acquire even one or two weapons. They suggest a small deterrent force operated by an international authority—good luck with that!

This is a thoughtful book which encourages rational people to think for themselves about the energy choices facing humanity in the coming decades. It counters emotional appeals and scare trigger words with the best antidote: numbers. Numbers which demonstrate, for example, that the inherent radiation of atoms in the human body (mostly C-14 and K-40) and the variation in natural background radiation from one place to another on Earth is vastly greater than the dose received from all kinds of nuclear technology. The Chernobyl and Three Mile Island accidents are examined in detail, and the lessons learnt for safely operating nuclear power stations are explored. I found the sections on nuclear weapons weaker and substantially more dated. Although the book was originally published well after the collapse of the Soviet Union, the perspective is still very much that of superpower confrontation, not the risk of proliferation to rogue states and terrorist groups. Certainly, responsibly disposing of the excess fissile material produced by the superpowers in their grotesquely hypertrophied arsenals (ideally by burning it up in civil power reactors, as opposed to insanely dumping it into a hole in the ground to remain a risk for hundreds of thousands of years, as some “green” advocates urge) is an important way to reduce the risks of proliferation, but events subsequent to the publication of this book have shown that states are capable of mounting their own indigenous nuclear weapons programs under the eyes of international inspectors. Will an “international community” which is incapable of stopping such clandestine weapons programs have any deterrent credibility even if armed with its own nuclear-tipped missiles?

An English translation of this book, entitled Megawatts and Megatons, is available.

Posted at 22:27 Permalink

Friday, September 4, 2009

Reading List: The Shameful Peace

Spotts, Frederic. The Shameful Peace. New Haven, CT: Yale University Press, 2008. ISBN 978-0-300-13290-8.
Paris between the World Wars was an international capital of the arts such as the world had never seen. Artists from around the globe flocked to this cosmopolitan environment which was organised more around artistic movements than nationalities. Artists drawn to this cultural magnet included the Americans Ezra Pound, Ernest Hemingway, F. Scott Fitzgerald, Gertrude Stein, Henry Miller, e.e. cummings, Virgil Thomson, and John Dos Passos; Belgians René Magritte and Georges Simenon; the Irish James Joyce and Samuel Beckett; Russians Igor Stravinsky, Sergei Prokofiev, Vladimir Nabokov, and Marc Chagall; and Spaniards Pablo Picasso, Joan Miró, and Salvador Dali, only to mention some of the nationalities and luminaries.

The collapse of the French army and British Expeditionary Force following the German invasion in the spring of 1940, leading to the armistice between Germany and France on June 22nd, turned this world upside down. Paris found itself inside the Occupied Zone, administered directly by the Germans. Artists in the “Zone libre” found themselves subject to the Vichy government's cultural decrees, intended to purge the “decadence” of the interwar years.

The defeat and occupation changed the circumstances of Paris as an artistic capital overnight. Most of the foreign expatriates left (but not all: Picasso, among others, opted to stay), so the scene became much more exclusively French. But remarkably, or maybe not, within a month of the armistice, the cultural scene was back up and running pretty much as before. The theatres, cinemas, concert and music halls were open, the usual hostesses continued their regular soirées with the customary attendees, and the cafés continued to be filled with artists debating the same esoterica. There were changes, to be sure: the performing arts played to audiences with a large fraction of Wehrmacht officers, known Jews were excluded everywhere, and anti-German works were withdrawn by publishers and self-censored thereafter by both authors and publishers in the interest of getting their other work into print.

The artistic milieu, which had been overwhelmingly disdainful of the Third Republic, transferred their scorn to Vichy, but for the most part got along surprisingly well with the occupier. Many attended glittering affairs at the German Institute and Embassy, and fell right in with the plans of Nazi ambassador Otto Abetz to co-opt the cultural élite and render them, if not pro-German, at least neutral to the prospects of France being integrated into a unified Nazi Europe.

The writer and journalist Alfred Fabre-Luce was not alone in waxing with optimism over the promise of the new era, “This will not sanctify our defeat, but on the contrary overcome it. Rivalries between countries, that were such a feature of nineteenth-century Europe, have become passé. The future Europe will be a great economic zone where people, weary of incessant quarrels, will live in security”. Drop the “National” and keep the “Socialist”, and that's pretty much the same sentiment you hear today from similarly-placed intellectuals about the odious, anti-democratic European Union.

The reaction of intellectuals to the occupation varied from enthusiastic collaboration to apathetic self-censorship and an apolitical stance, but rarely did it cross the line into active resistance. There were some underground cultural publications, and some well-known figures did contribute to them (anonymously or under a pseudonym, bien sûr), but for the most part artists of all kinds got along, and adjusted their work to the changed circumstances so that they could continue to be published, shown, or performed. A number of prominent figures emigrated, mostly to the United States, and formed an expatriate French avant garde colony which would play a major part in the shift of the centre of the arts world toward New York after the war, but they were largely politically disengaged while the war was underway.

After the Liberation, the purge (épuration) of collaborators in the arts was haphazard and inconsistent. Artists found themselves defending their work and actions during the occupation before tribunals presided over by judges who had, after the armistice, sworn allegiance to Pétain. Some writers received heavy sentences, up to and including death, while their publishers, who had voluntarily drawn up lists of books to be banned, confiscated, and destroyed got off scot-free and kept right on running. A few years later, as the Trente Glorieuses began to pick up steam, most of those who had not been executed found their sentences commuted and went back to work, although the most egregious collaborators saw their reputations sullied for the rest of their lives. What could not be restored was the position of Paris as the world's artistic capital: the spotlight had moved on to the New World, and New York in particular.

This excellent book stirs much deeper thoughts than just those of how a number of artists came to terms with the occupation of their country. It raises fundamental questions as to how creative people behave, and should behave, when the institutions of the society in which they live are grossly at odds with the beliefs that inform their work. It's easy to say that one should rebel, resist, and throw one's body onto the gears to bring the evil machine to a halt, but it's entirely another thing to act in such a manner when you're living in a city where the Gestapo is monitoring every action of prominent people and you never know who may be an informer. Lovers of individual liberty who live in the ever-expanding welfare/warfare/nanny states which rule most “developed” countries today will find much to ponder in observing the actions of those in this narrative, and may think twice the next time they're advised to “be reasonable; go along: it can't get that bad”.

Posted at 00:36 Permalink