Tuesday, February 23, 2010


The tragic event of the deranged and frustrated Piper pilot (I learned to fly in a Cessna, so I think this applies to ALL Piper pilots. Okay, okay, just kidding!!) that went off his rocker last week, and crashed into the IRS building in Austin (sadly killing an employee) has no doubt got us all thinking 1) about the family of the IRS employee, and 2) about the family of the deranged lunatic. Our sincerest heartfelt sympathy goes out to those families.

We shall continue to reflect with sorrow over the sad consequences that childish and sad act of selfishness and evil had for the loved ones left behind. And, as "critic"-al thinkers, I have no doubt that most of us are also wondering what the longer term consequences to the General Aviation community might be, and how that act of deviance, might result in some further deviation from the norm we used to know in pre- 9-11 days, particularly regarding smaller airports where many of us hang out to watch planes and cheer the marvel of flight. (And drink beer when no one is watching, judging from the empties in the parking lots...). Or even perform delightful feats of challenging the laws of gravity- and probability, in my case.

(At least according to the many unkind, and unsolicited, critiques of my landing "style". No doubt, most are from jealous Piper enthusiasts, who are envious of a 172's ability to gracefully bounce about half a wingspan, instead of rather blandly plopping onto the runway- much like rather uncerimoniously dropping a wet towel. In stark contrast to the playful and spirited response of, say, dropping a golf ball onto a concrete sidewalk. From a third story window or so).

While we continue to grieve for the affected families of last week's tragedy, we also contemplate what coming actions might be taken in a constructive way, and perhaps well intentioned, but not quite so productive ways. One of our blog's great thinkers (and satirist/parody-ists) has put his formidable powers of analysis towards what might be the resulting aftermath of recent events.

Without further ado, here's our friend Black Tulips's first (of many, I hope) return engagement as a "headliner" (I suppose I give the Cessna's headliners a pretty good work out) on A.C. & E. :

February 20, 2010 – Washington, DC

The world still reels from the shock of Texas pilot Joseph Stack flying his Piper Cherokee into a Federal office building in Austin. The man’s grudge against the IRS ended in a fiery suicide attack. The Federal government has scrambled to react to this homegrown tragedy which some consider a domestic terrorist act. The Transportation Security Administration (TSA) is currently without a leader so Janet Napolitano, Secretary of the Department of Homeland Security, has stepped into the breach. “This is Nine-Eleven all over again except the terrorist had lighter skin and no accent”, she said. “I told you this was going to happen. The Obama Administration gave business and general aviation one chance too many.”

Napolitano continued, “I am pleased to announce today the formation of the Total Air Marshal Program (TAMP). There are 240,000 active general aviation aircraft in the United States and an Air Marshal will be assigned to each aircraft. With over 600,000 active certificated pilots in the United States we can’t have an Air Marshal for every pilot – but we can have one for every plane.”

At this morning’s press conference she turned to Rahm Emmanuel, White House Chief of Staff, who said, “We are pleased with this rapid reaction to a domestic terrorist threat. We can’t let some retard in a bug smasher hold up tax collections in Texas. President Obama considers this an example of his dynamic and flexible Stimulus Package. Now there is a demand for 240,000 new jobs that weren’t there yesterday. Hotels and restaurants around the country will benefit from the Air Marshal’s spending.”

Emmanuel added with emphasis, “This should also make the Second Amendment folks happy as the Government is going to purchase a quarter million handguns. Nine millimeter is the preferred caliber as it will minimize collateral damage to pressurized aircraft.”
Next Randy Babbitt, Administrator of the Federal Aviation Administration (FAA), took the microphone, “We realize that some will consider this an inconvenience and overreaction. In order to ease the application of this rule we made several important changes to the Federal Air Regulations (FARs). No longer will there be a limit on the number of crew or passengers in one seat belt at a time – independent of age and weight. Also you can expect a new set of pages for your Pilots Operating Handbook (POH). Depending on runway length and density altitude, pilots need not consider the addition weight of the Air Marshal and their luggage. In other words aircraft owners can add about 250 pounds to takeoff weight without regard to center of gravity.”

Secretary Napolitano offered concluding remarks, “We realize some will consider this expansion of the Air Marshal program an intrusion. For that reason the Federal government is seeking wide diversity in the Air Marshals. For the older family-oriented flyers we will offer retired law enforcement officials. For the younger and more adventurous we have several possibilities. Several of Tiger Woods’ mistresses have signed up and are in training. However we do have a shortage of gay, lesbian, bisexual and transgender Air Marshals… especially the latter. I encourage all who have an interest in joining the rapidly growing Total Air Marshal Program for a bright future in the United States Government.”

Thanks BT- it's a great piece, with of course no disreverence for the deceased whatsoever- and I laughed harder than those whiny Piper guys who watch me land!

Sunday, February 14, 2010

"Modern" Science (Part 1 of 3): da Vinci to Daniel Bernoulli (b.1452 - b.1700)

I think there is some law of the internet that says eventually every blog thread, if discussed long enough, will involve UFO's and Nazis. Or maybe both at the same time.
I suppose a reasonable corollary (say- there's a new one out this year!) is that every science-related blog will eventually discuss daVinci and Einstein. Or maybe both at the same time.
(So here we go!)

The longest topic in the "general" part of the A&P program is electricity- which just concluded last Friday. During the course of, ah, the course, I became curious about the time line involving the notable scientists, physicists, and mathematicians involved with electricity, and more generally, involved in the engineering and technology we are using in general aviation today.
Where to start? Actually, I have always wanted to read a good book on the History of Mathematics. There are number-ous (joke- get it- probably not- it's a bad joke), er, numerous books out there on just such a topic, and most college math departments offer some sort of class on the subject. But I haven't found one with lots of pictures- just lots of boring words and funny looking symbols). So, I have been doing some research using good 'ole Wikipeida.

Having a keen mind for trivia (and not much else), I frequently see familiar names when reference reading has me hop between technical subjects, particularly so for more dated references.

I have been coming the term "polymath" ("A polymath -Greek polymathes, for "having learned much"- is a person whose expertise spans a significant number of subject areas. In less formal terms, a polymath (or polymathic person) may simply be someone who is very knowledgeable. Most ancient scientists were polymaths by today's standards".)

Some time ago, I saw a museum exhibit of part of the Codex Leicester works of Leonardo da Vinci. It was rather humbling to contemplate the curiosity, ingenuity, intuition, and insight of this man of centuries ago. I start our tour of technical contributors to aviation with him. I'll end with those born in the late 1880's, and contributed throughout the first half of the 20th century. (I think most of us are relatively familiar with the contributions made in the last half of that century- and if not, the material is more well documented should such an interest arise).

There isn't enough room to go very deep here- I encourage all to read up on their "favorites" (Kepler is one of mine):

1452 da Vinci (April 15, 1452 – May 2, 1519)
1473 Copernicus (19 February 1473 – 24 May 1543)
1475 Michelangelo (March 1475 – 18 February 1564)
1564 Galileo (15 February 1564 – 8 January 1642)
1571 Kepler (27 December, 1571 – 15 November, 1630)
1596 Descartes (31 March 1596 – 11 February 1650)
1616 Wallis (23 November, 1616 – 28 October, 1703)
1623 Pascal (19 June, 1623 – 19 August, 1662)
1627 Boyle (25 January 1627 – 31 December 1691)
1629 Huygens (14 April 1629 – 8 July 1695)
1635 Hooke (18 July 1635 – 3 March 1703)
1643 Newton (4 January 1643 – 31 March 1727 )
1646 Leibniz (1 July 1646 – 14 November 1716)
1654 Jakob Bernoulli (27 December 1654 – 16 August 1705)
1663 Amontons (August 31, 1663 – October 11, 1705)
1686 Fahrenheit (14 May 1686 – 16 September 1736)
1700 Daniel Bernoulli (8 February 1700 – 8 March 1782)

1452 da Vinci (April 15, 1452 – May 2, 1519)
"an Italian polymath: painter, sculptor, architect, musician, scientist, mathematician, engineer, inventor, anatomist, geologist, botanist and writer. Leonardo has often been described as the archetype of the Renaissance man, a man whose unquenchable curiosity was equaled only by his powers of invention. He is widely considered to be one of the greatest painters of all time and perhaps the most diversely talented person ever to have lived...As a scientist, he greatly advanced the state of knowledge in the fields of anatomy, civil engineering, optics, and hydrodynamics......the father of modern tribology as he studied an incredible manifold of tribological subtopics such as: friction, wear, bearing materials, plain bearings, lubrication systems, gears, screw-jacks, and rolling-element bearings...Leonardo was and is renowned primarily as a painter. Two of his works, the Mona Lisa and The Last Supper, are the most famous, most reproduced and most parodied portrait and religious painting of all time, respectively, their fame approached only by Michelangelo's Creation of Adam. Leonardo's drawing of the Vitruvian Man is also regarded as a cultural icon...He conceptualised a helicopter, a tank, concentrated solar power, a calculator, the double hull and outlined a rudimentary theory of plate tectonics...science and engineering are as impressive and innovative as his artistic work, recorded in notebooks comprising some 13,000 pages of notes and drawings, which fuse art and natural philosophy (the forerunner of modern science). These notes were made and maintained daily throughout Leonardo's life and travels, as he made continual observations of the world around him...As an artist, he quickly became master of topographic anatomy, drawing many studies of muscles, tendons and other visible anatomical features...As a successful artist, he was given permission to dissect human corpses at the Hospital of Santa Maria Nuova in Florence and later at hospitals in Milan and Rome. From 1510 to 1511 he collaborated in his studies with the doctor Marcantonio della Torre and together they prepared a theoretical work on anatomy for which Leonardo made more than 200 drawings...For much of his life, Leonardo was fascinated by the phenomenon of flight, producing many studies of the flight of birds, including his c. 1505 Codex on the Flight of Birds, as well as plans for several flying machines, including a helicopter and a light hang glider."

1473 Copernicus (19 February 1473 – 24 May 1543)
"The first astronomer to formulate a comprehensive heliocentric cosmology, which displaced the Earth from the center of the universe...Copernicus' epochal book, De revolutionibus orbium coelestium (On the Revolutions of the Celestial Spheres), published just before his death in 1543, is often regarded as the starting point of modern astronomy and the defining epiphany that began the scientific revolution. His heliocentric model, with the Sun at the center of the universe, demonstrated that the observed motions of celestial objects can be explained without putting Earth at rest in the center of the universe. His work stimulated further scientific investigations, becoming a landmark in the history of science that is often referred to as the Copernican Revolution...Among the great polymaths of the Renaissance, Copernicus was a mathematician, astronomer, physician, quadrilingual polyglot, classical scholar, translator, artist, Catholic cleric, jurist, governor, military leader, diplomat and economist. Among his many responsibilities, astronomy figured as little more than an avocation — yet it was in that field that he made his mark upon the world".

1475 Michelangelo (March 1475 – 18 February 1564)
"An Italian Renaissance painter, sculptor, architect, poet, and engineer. Despite making few forays beyond the arts, his versatility in the disciplines he took up was of such a high order that he is often considered a contender for the title of the archetypal Renaissance man, along with his rival and fellow Italian Leonardo da Vinci....Michelangelo's output in every field during his long life was prodigious; when the sheer volume of correspondence, sketches, and reminiscences that survive is also taken into account, he is the best-documented artist of the 16th century."

1564 Galileo (15 February 1564 – 8 January 1642)
"an Italian physicist, mathematician, astronomer, and philosopher who played a major role in the Scientific Revolution. His achievements include improvements to the telescope and consequent astronomical observations, and support for Copernicanism. Galileo has been called the "father of modern observational astronomy," the "father of modern physics," the "father of science," and "the Father of Modern Science." Stephen Hawking says, "Galileo, perhaps more than any other single person, was responsible for the birth of modern science...The motion of uniformly accelerated objects, taught in nearly all high school and introductory college physics courses, was studied by Galileo as the subject of kinematics. His contributions to observational astronomy include the telescopic confirmation of the phases of Venus, the discovery of the four largest satellites of Jupiter (named the Galilean moons in his honour), and the observation and analysis of sunspots. Galileo also worked in applied science and technology, inventing an improved military compass and other instruments."

1571 Kepler (27 December, 1571 – 15 November, 1630
"A German mathematician, astronomer and astrologer, and key figure in the 17th century scientific revolution. He is best known for his eponymous laws of planetary motion, codified by later astronomers based on his works Astronomia nova, Harmonices Mundi, and Epitome of Copernican Astronomy. They also provided one of the foundations for Isaac Newton's theory of universal gravitation...During his career, Kepler was a mathematics teacher at a seminary school in Graz, Austria, an assistant to astronomer Tycho Brahe..He also did fundamental work in the field of optics, invented an improved version of the refracting telescope (the Keplerian Telescope), and helped to legitimize the telescopic discoveries of his contemporary Galileo Galilei."

1596 Descartes (31 March 1596 – 11 February 1650)
"A French philosopher, mathematician, physicist, and writer who spent most of his adult life in the Dutch Republic. He has been dubbed the "Father of Modern Philosophy", and much of subsequent Western philosophy is a response to his writings, which continue to be studied closely to this day. In particular, his Meditations on First Philosophy continues to be a standard text at most university philosophy departments. Descartes' influence in mathematics is also apparent, the Cartesian coordinate system—allowing geometric shapes to be expressed in algebraic equations—being named for him. He is credited as the father of analytical geometry. Descartes was also one of the key figures in the Scientific Revolution...As the inventor of the Cartesian coordinate system, Descartes founded analytic geometry, the bridge between algebra and geometry, crucial to the discovery of infinitesimal calculus and analysis."

1616 Wallis (23 November, 1616 – 28 October, 1703)
"an English mathematician who is given partial credit for the development of modern calculus. Between 1643 and 1689 he served as chief cryptographer for Parliament and, later, the royal court. He is also credited with introducing the symbol for infinity...Wallis made significant contributions to trigonometry, calculus, geometry, and the analysis of infinite series...Wallis introduced the term "continued fraction"...In 1655, Wallis published a treatise on conic sections in which they were defined analytically. This was the earliest book in which these curves are considered and defined as curves of the second degree. It helped to remove some of the perceived difficulty and obscurity of René Descartes' work on analytic geometry...(elastic collision), Wallis considered also imperfectly elastic bodies (inelastic collision). This was followed in 1669 by a work on statics (centres of gravity), and in 1670 by one on dynamics: these provide a convenient synopsis of what was then known on the subject...One aspect of Wallis's mathematical skills has not yet been mentioned, namely his great ability to do mental calculations. He slept badly and often did mental calculations as he lay awake in his bed. One night he calculated the square root of a number with 53 digits in his head. In the morning he dictated the 27 digit square root of the number, still entirely from memory."

1623 Pascal(19 June, 1623 - 19 August 1662)
"A French mathematician, physicist, and religious philosopher. He was a child prodigy who was educated by his father, a civil servant. Pascal's earliest work was in the natural and applied sciences where he made important contributions to the construction of mechanical calculators, the study of fluids, and clarified the concepts of pressure and vacuum by generalizing the work of Evangelista Torricelli. Pascal also wrote in defense of the scientific method....Pascal was a mathematician of the first order. He helped create two major new areas of research. He wrote a significant treatise on the subject of projective geometry at the age of sixteen, and later corresponded with Pierre de Fermat on probability theory, strongly influencing the development of modern economics and social science. Following Galileo and Torricelli, in 1646 he refuted Aristotle's followers who insisted that nature abhors a vacuum. His results caused many disputes before being accepted."

1627 Boyle (25 January 1627 – 31 December 1691)
" an Irish natural philosopher, chemist, physicist, and inventor, also noted for his writings in theology. He is best known for Boyle's Law. Although his research and personal philosophy clearly has its roots in the alchemical tradition, he is largely regarded today as the first modern chemist, and therefore one of the founders of modern chemistry. Among his works, "The Sceptical Chymist", is seen as a cornerstone book in the field of chemistry.
While still a child, Robert learned to speak Latin, Greek, and French. He was not yet eight years old when, following the death of his mother, he was sent to Eton College in England...After spending over three years at Eton, Robert traveled abroad with a French tutor. They visited Italy in 1641, and remained in Florence during the winter of that year, studying the "paradoxes of the great star-gazer" Galileo Galibei- Galileo was elderly, but still alive in Florence in 1641.
Boyle returned to England from the Continent in mid 1644 with a keen interest in science. His father had died the previous year and had left him the manor of Stalbridge in Dorset, together with some estates in Ireland. From that time, he devoted his life to scientific research, and soon took a prominent place in the band of inquirers, known as the "Invisible College", who devoted themselves to the cultivation of the "new philosophy". They met frequently in London, often at Gresham College; some of the members also had meetings at Oxford where Boyle went to reside in 1654. Reading in 1657 of Otto von Guericke's air-pump, he set himself with the assistance of Robert Hooke to devise improvements in its construction, and with the result, the "machina Boyleana" or "Pneumatical Engine", finished in 1659, he began a series of experiments on the properties of air.
With all the important work he accomplished in physics -the enunciation of Boyle's law, the discovery of the part taken by air in the propagation of sound, and investigations on the expansive force of freezing water, on specific gravities and refractive powers, on crystals, on electricity, on color, on hydrostatics, etc. - chemistry was his peculiar and favourite study.
Besides being a busy natural philosopher, Boyle devoted much time to theology, showing a very decided leaning to the practical side and an indifference to controversial polemics. As a director of the East India Company he spent large sums in promoting the spread of Christianity in the East, contributing liberally to missionary societies, and to the expenses of translating the Bible or portions of it into various languages."

1629 Huygens (14 April 1629 – 8 July 1695)
"a prominent Dutch mathematician, astronomer, physicist, horologist, and writer of early science fiction. His work included early telescopic studies elucidating the nature of the rings of Saturn and the discovery of its moon Titan, the invention of the pendulum clock and other investigations in timekeeping, and studies of both optics and the centrifugal force....Huygens achieved note for his argument that light consists of waves, now known as the Huygens–Fresnel principle, which became instrumental in the understanding of wave-particle duality. He generally receives credit for his discovery of the centrifugal force, the laws for collision of bodies, for his role in the development of modern calculus and his original observations on sound perception (see repetition pitch). Huygens is seen as the first theoretical physicist as he was the first to use formulae in physics"

1635 Hooke (18 July 1635 – 3 March 1703)
"A British natural philosopher, architect and polymath who played an important role in the scientific revolution, through both experimental and theoretical work...Hooke is known for his law of elasticity (Hooke's Law), his book, Micrographia, and for coining the term "cell" to describe the basic unit of life. Even now there is much less written about him than might be expected from the sheer industry of his life: he was at one time simultaneously the curator of experiments of the Royal Society and a member of its council, Gresham Professor of Geometry and a Surveyor to the City of London after the fire of 1666, in which capacity he appears to have performed more than half of all the surveys after the fire. He was also an important architect of his time, though few of his buildings now survive and some of those are generally misattributed, and was instrumental in devising a set of planning controls for London whose influence remains today. Allan Chapman has characterised him as "England's Leonardo"....he was employed as an assistant to Thomas Willis and to Robert Boyle, for whom he built the vacuum pumps used in Boyle's gas law experiments. He built some of the earliest Gregorian telescopes, observed the rotations of Mars and Jupiter, and, based on his observations of fossils, was an early proponent of biological evolution. He investigated the phenomenon of refraction, deducing the wave theory of light, and was the first to suggest that matter expands when heated and that air is made of small particles separated by relatively large distances. He performed pioneering work in the field of surveying and map-making and was involved in the work that led to the first modern plan-form map, though his plan for London on a grid system was rejected in favour of rebuilding along the existing routes. He also came near to deducing that gravity follows an inverse square law, and that such a relation governs the motions of the planets, an idea which was subsequently developed by Newton...after a long period of relative obscurity he is now recognized as one of the most important scientists of his age."

1643 Newton (4 January 1643 – 31 March 1727 )
"An English physicist, mathematician, astronomer, natural philosopher, alchemist, and theologian who is considered by many scholars and members of the general public to be one of the most influential men in human history. His 1687 publication of the Philosophiæ Naturalis Principia Mathematica (usually called the Principia) is considered to be among the most influential books in the history of science, laying the groundwork for most of classical mechanics. In this work, Newton described universal gravitation and the three laws of motion which dominated the scientific view of the physical universe for the next three centuries. Newton showed that the motions of objects on Earth and of celestial bodies are governed by the same set of natural laws by demonstrating the consistency between Kepler's laws of planetary motion and his theory of gravitation, thus removing the last doubts about heliocentrism and advancing the scientific revolution...Newton also built the first practical reflecting telescope and developed a theory of colour based on the observation that a prism decomposes white light into the many colours that form the visible spectrum. He also formulated an empirical law of cooling and studied the speed of sound....In mathematics, Newton shares the credit with Gottfried Leibniz for the development of the differential and integral calculus. He also demonstrated the generalised binomial theorem, developed the so-called "Newton's method" for approximating the zeroes of a function, and contributed to the study of power series...Newton remains influential to scientists, as demonstrated by a 2005 survey of members of Britain's Royal Society asking who had the greater effect on the history of science and had the greater contribution to humankind, Newton or Albert Einstein. Royal Society scientists deemed Newton to have made the greater overall contribution on both."

1646 Leibniz (1 July 1646 – 14 November 1716)
"A German philosopher, polymath and mathematician who wrote primarily in Latin and French...He occupies a grand place in both the history of philosophy and the history of mathematics. He invented infinitesimal calculus independently of Newton, and his notation has been in general use since then. He also invented the binary system, the foundation of virtually all modern computer architectures. In philosophy, he is mostly remembered for optimism, i.e. his conclusion that our universe is, in a restricted sense, the best possible one God could have made. He was, along with René Descartes and Baruch Spinoza, one of the three greatest 17th-century rationalists and anticipates modern logic and analysis, but his philosophy also looks back to the scholastic tradition, in which logic was an important part. Leibniz also made major contributions to physics and technology, and anticipated notions that surfaced much later in biology, medicine, geology, probability theory, psychology, linguistics, and information science. He also wrote on politics, law, ethics, theology, history, philosophy and philology, even occasional verse. His contributions to this vast array of subjects are scattered in journals and in tens of thousands of letters and unpublished manuscripts."

1654 Jakob Bernoulli (27 December 1654 – 16 August 1705)
"Was one of the many prominent mathematicians in the Bernoulli family...Following his father's wish, Jacob studied theology and entered the ministry. But contrary to the desires of his parents, he also studied mathematics and astronomy...He traveled throughout Europe from 1676 to 1682, learning about the latest discoveries in mathematics and the sciences. This included the work of Robert Boyle and Robert Hooke...was one of the many prominent mathematicians in the Bernoulli family...He became familiar with calculus through a correspondence with Gottfried Leibniz, then collaborated with his brother Johann on various applications, notably publishing papers on transcendental curves (1696) and isoperimetry (1700, 1701). In 1690, Jacob became the first person to develop the technique for solving separable differential equations...Upon returning to Basel in 1682, he founded a school for mathematics and the sciences. He was appointed professor of mathematics at the University of Basel in 1687, remaining in this position for the rest of his life...Jacob is best known for the work Ars Conjectandi (The Art of Conjecture), published eight years after his death in 1713 by his nephew Nicholas. In this work, he described the known results in probability theory and in enumeration, often providing alternative proofs of known results. This work also includes the application of probability theory to games of chance and his introduction of the theorem known as the law of large numbers. The terms Bernoulli trial and Bernoulli numbers result from this work."

1663 Amontons (August 31, 1663 – October 11, 1705)
"was born in Paris, France. His father was a lawyer from Normandy who had moved to the French capital. While still young, Guillaume lost his hearing, which may have motivated him to focus entirely on science. He never attended a university, but was able to study mathematics, the physical sciences, and celestial mechanics. He also spent time studying the skills of drawing, surveying, and architecture...Among his contributions to scientific instrumentation were improvements to the barometer (1695), hygrometer (1687), and thermometer (1695), particularly for use of these instruments at sea. He also demonstrated an optical telegraph and proposed the use of his clepsydra[1] (water clock) for keeping time on a ship at sea...Amontons investigated the relationship between pressure and temperature in gases though he lacked accurate and precise thermometers. Though his results were at best semi-quantitative, he established that the pressure of a gas increases by roughly one-third between the temperatures of cold and the boiling point of water[2]. This was a substantial step towards the subsequent gas laws and, in particular, Charles's law...His work led him to speculate that a sufficient reduction in temperature would lead to the disappearance of pressure. Thus, he is the first researcher to discuss the concept of an absolute zero of temperature...In 1699, Amontons published his rediscovery of the laws of friction first put forward by Leonardo da Vinci. Though they were received with some scepticism, the laws were verified by Charles-Augustin de Coulomb in 1781."

1686 Fahrenheit (14 May 1686 – 16 September 1736)
"At age 16, Daniel Gabriel Fahrenheit began training as a merchant in Amsterdam after his parents died on August 14 in 1701 from accidentally eating poisonous mushrooms. However, Fahrenheit's interest in natural science caused him to begin studies and experimentation in that field. From 1707, he traveled to Berlin, Halle, Leipzig, Dresden, Copenhagen, and also to his hometown, where his brother still lived. During that time, Fahrenheit met or was in contact with Ole Rømer, Christian Wolff, and Gottfried Leibniz. In 1717, Fahrenheit settled in The Hague with the trade of glassblowing, making barometers, altimeters, and thermometers. From 1718 onwards, he lectured in chemistry in Amsterdam...was a physicist and engineer who determined a temperature scale now named after him."

1700 Daniel Bernoulli (8 February 1700 – 8 March 1782)
"Was a Dutch-Swiss mathematician and was one of the many prominent mathematicians in the Bernoulli family. He is particularly remembered for his applications of mathematics to mechanics, especially fluid mechanics, and for his pioneering work in probability and statistics. Bernoulli's work is still studied at length by many schools of science throughout the world....His earliest mathematical work was the Exercitationes (Mathematical Exercises), published in 1724 with the help of Goldbach. Two years later he pointed out for the first time the frequent desirability of resolving a compound motion into motions of translation and motions of rotation. His chief work is his Hydrodynamique (Hydrodynamica), published in 1738; it resembles Joseph Louis Lagrange's Mécanique Analytique in being arranged so that all the results are consequences of a single principle, namely, conservation of energy. This was followed by a memoir on the theory of the tides, to which, conjointly with the memoirs by Euler and Colin Maclaurin, a prize was awarded by the French Academy: these three memoirs contain all that was done on this subject between the publication of Isaac Newton's Philosophiae Naturalis Principia Mathematica and the investigations of Pierre-Simon Laplace. Bernoulli also wrote a large number of papers on various mechanical questions, especially on problems connected with vibrating strings, and the solutions given by Brook Taylor and by Jean le Rond d'Alembert...Daniel Bernoulli was also the author in 1738 of Specimen theoriae novae de mensura sortis (Exposition of a New Theory on the Measurement of Risk), in which the St. Petersburg paradox was the base of the economic theory of risk aversion, risk premium and utility...One of the earliest attempts to analyze a statistical problem involving censored data was Bernoulli's 1766 analysis of smallpox morbidity and mortality data to demonstrate the efficacy of vaccination...He is the earliest writer who attempted to formulate a kinetic theory of gases, and he applied the idea to explain Boyle's law...He worked with Euler on elasticity and the development of the Euler-Bernoulli beam equation. Bernoulli's principle is of critical use in aerodynamics."

Tuesday, February 2, 2010

What I Learned in School This Week...

Well, I must confess, I'm not quite as studious as Thomas Edison, shown to the right, in this dated photograph (of a likewise rather dated Mr. Edison). But after the cookies and milk run out, I do pay some attention in class (Airframe and Powerplant).

One of the interesting activities was a field trip to a local repair shop, where there was a demonstration of working with composites, especially repairing them after some ham-fisted damage is done. (The instructor stared at me a lot during this demonstration, for some reason or other). It turns out that, much to my surprise, that composites are really pretty darned easy to repair. The basic technique is to-
1) Identify the area of damage
2) Remove damaged material
3) Glue new stuff in
That all sounds simple, and when performed by someone familiar with the methods, it really IS simple.

A little tap hammer is used to acoustically listen for delaminations and damage, although there are acoustic "scanners" which can do the same thing with ultrasound.
Then material is sanded down until the delamination is removed.
If a honeycomb core is used, even it can be cut out and "plugged" with a honeycomb insert (and lots of glue/resin).

Layers of Carbon Fiber fabric are then laid over the damage, in orientation described dictated by the specific location (and load path at that location) as described in a repair manual. Plies are alternated 0-90 and 45-135 degrees, up to 4 plies thick, and then resin is worked into the fabric and heat cured. Another set of up to 4 plies is laid, and cured. Etc, until the desired strength is obtained.
Lightning strike fiber (copper mesh, or some such) is then laid over the repair- some sort of smoothing jel for a nice finish is applied, and it's cured and painted. Typically a repair takes one to two shifts, I was told. Neat!

One thing we were cautioned about regarded working with the materials. The resins of course, are rather nasty. But fragments/filliments of the carbon fiber itself are pretty bad news too: the work bench was actually a vacuum table, to capture the dust. Wikipedia has a nice article about Carbon Fibers ("Carbon fibers are the closest to asbestos in a number of properties...").

Although discovered in the good ole US of A, it seems our plucky British friends were early adopters of this rather, um, "disruptive" technology:

"The high potential strength of carbon fiber was realized in 1963 in a process developed at the Royal Aircraft Establishment at Farnborough, Hampshire.. The process was patented by the Ministry of Defence and then licensed by the NRDC to three British companies: Rolls-Royce, already making carbon fiber, Morganite and Courtaulds.. They were able to establish industrial carbon fiber production facilities within a few years, and Rolls-Royce took advantage of the new material's properties to break into the American market with its RB-211 aero-engine.

"Even then, though, there was public concern over the ability of British industry to make the best of this breakthrough. In 1969 a House of Commons select committee inquiry into carbon fiber prophetically asked: "How then is the nation to reap the maximum benefit without it becoming yet another British invention to be exploited more successfully overseas?" Ultimately, this concern was justified. One by one the licensees pulled out of carbon-fiber manufacture. Rolls-Royce's interest was in state-of-the-art aero-engine applications. Its own production process was to enable it to be leader in the use of carbon-fiber reinforced plastics. In-house production would typically cease once reliable commercial sources became available.

"Unfortunately, Rolls-Royce pushed the state-of-the-art too far, too quickly, in using carbon fiber in the engine's compressor blades, which proved vulnerable to damage from bird impact. What seemed a great British technological triumph in 1968 quickly became a disaster as Rolls-Royce's ambitious schedule for the RB-211 was endangered. Indeed, Rolls-Royce's problems became so great that the company was eventually nationalized by Edward Heath's Conservative government in 1971 and the carbon-fiber production plant sold off to form Bristol Composites."

Now it doesn't quite date back to Edison's time (February 11, 1847 – October 18, 1931), but some keen eared folks (unfortunately, Mr. Edison was rather deaf) will recall that the RB211 was destined for the Lockheed L1011.

"Because Lockheed was itself in a vulnerable position, the government required that the US government guarantee the bank loans that Lockheed needed to complete the L-1011 project. Despite some opposition, the US government provided these guarantees. In May 1971, a new company called "Rolls-Royce (1971) Ltd." acquired the assets of Rolls-Royce from the Receiver, and shortly afterwards signed a new contract with Lockheed. This revised agreement cancelled penalties for late delivery, and increased the price of each engine by £110,000".

"A major differentiator between the L-1011 and the DC-10 was Lockheed's selection of the Rolls-Royce RB211 engine for the L-1011. As originally designed, the RB211 turbofan was an advanced three-spool design with a carbon fibre fan, which would have better efficiency and power-to-weight than any competing design. This would make the L-1011 more efficient, a major selling point.

"American Airlines opted for the Douglas DC-10, although it had shown considerable interest in the L-1011. American's intent in doing so was to convince Douglas to lower its price for the DC-10, which it did. Without the support of American, the TriStar was launched on orders from TWA and Eastern Air Lines. Although the TriStar's design schedule closely followed that of its competitor, Douglas beat Lockheed to market by a year due to delays in power plant development. In February 1971, after massive development costs associated with the RB211, Rolls-Royce went into receivership. This halted L-1011 final assembly and Lockheed investigated the possibility of a US engine supplier, one option presented would have been the potential outsource of the RB-211 production to Orenda, but by then it was considered too late to change engine suppliers to either General Electric, or Pratt & Whitney.

"The British government agreed to approve a large state subsidy to restart Rolls-Royce operations on condition the U.S. government guarantee the bank loans Lockheed needed to complete the L-1011 project...

"Kenneth Keith, the new chairman who had been appointed to rescue the company (RR), persuaded Stanley Hooker to come out of retirement and return to Rolls. As technical director he led a team of other retirees to fix the remaining problems on the RB211-22. The engine was finally certified on 14 April 1972,[11] about a year later than originally planned, and the first TriStar entered service with Eastern Air Lines on 26 April 1972. Hooker was knighted for his role in 1974."
It is interesting to note that the original Eclipse engine (the Williams EJ-22) was also a three-spool design. Disruptive engine technology is a real pain!

Speaking of that...the name Orenda made MY ears perk up (although this late at night, that's about all). Fellow GA propeller heads (as opposed to turbofan fans), will perhaps recall one of the pseudo urban legands of late, the Orenda V8.

"The Orenda OE600 is a 600 hp-class liquid-cooled 8-cylinder V-block aircraft engine intended to re-introduce piston power to aircraft normally powered by the famous Pratt & Whitney Canada PT6 turboprot. The piston engine offers much better fuel economy, which Orenda Aerospace felt would be attractive for older aircraft whose engines were reaching the end of their lifespan. However, changes in Orenda's business in the post- 9/11 time frame led to the project being canceled.

"Unfortunately, the events of 9/11 required Orenda to re-focus entirely on their military projects, and the OE600 project was canceled. The design was later purchased by a group of investors who intend to sell the engine under the Texas Recip brand, but it is unclear if this project is continuing. On August 29, 2006 the president of Texas Recip, Paul Thorpe was sentenced to 3 years and five months for defrauding investors, telling them the money was being invested in the engine project, or other investments, when it was actually being used to pay off investors in a previous scheme.

"More recently the project has been picked up by TRACE Engines of Midland, Texas. Yorkton Aircraft is handling Canadian installations in agricultural aircraft."

While current VLJ Engines are Candian (PWC-61X), Orenda is also Canadian.

It seems the disruptive engine game can lead to knighthood, a Collier trophy, or a jail sentence- (overall, I'd say Eclipse should be pleased with the Collier! :)