Jet Engines and Michelangelo’s “Moses”

What do these two “finished products” have in common?

how-to-build-a-rolls-royce-trent-1000-jet-engine-used-in-the-boeing-787_5[1]SI Exif
The “reason” side of us acting alone would likely prompt the quick response, “Not much!” After some careful thought, our “reflective” side could provide some convincing arguments to support the contention that these two seemingly diverse objects, one from the world of technology, one from the art world, actually have much in common. Here is the way I see it.

The famous “Moses” at Rome, sculpted in hard marble by Michelangelo, represents the epitome of man’s ability to represent life and human nature using artistic mediums. In Moses, the inherent artistic genius of Michelangelo is brought to full bloom by the countless hours of diligent study and practice he devoted to mastering the techniques of working with marble. One man’s extreme dedication to his artistic cause has given us such priceless art as Moses, the Pieta, and the Sistine Chapel just to name a few.

As with Michelangelo’s Moses, the modern turbojet engine used in today’s airliners is the epitome of a product which demanded extreme dedication to a cause – only, here, the dedication extends over decades, indeed centuries, as armies of thinkers, scientists, and engineers fought to understand nature and natural forces.

Michelangelo’s Moses began as nothing more than a rudimentary “chunk” of marble; correspondingly, man’s knowledge of the various technologies inherent in modern turbojet engine designs ranged from rudimentary to non-existent as recently as four hundred years ago – well after Moses emerged from his marble prison. Michelangelo at least had his toolbox of fairly refined chisels and sculpting tools with which to work. The early “natural philosophers,” as early scientists and technologists were called, had little with which to work. They initially faced a confusing scramble of nature’s puzzle-pieces requiring painstaking assembly into a larger picture before true technology was possible.

Even allowing for whatever handed-down knowledge the artist might have received from mentors and colleagues, I see Moses more as the ultimate tribute to a single man’s talent and determination. I see the modern turbojet engine (and virtually all other technological wonders) as the ultimate tribute to mankind as a whole – the cumulative outcome of generations who worked to build our technology hierarchies. The iPhone, the modern automobile, the internet – these and all such technology triumphs are a tribute to the human spirit and its desire to “know.”

Highly-Polished Works of Art!

Michelangelo sculpted Moses cut-by-cut, chip-by-chip. And when Moses’ rough form finally emerged from the block of marble, he polished the innumerable rough spots – over and over again until the rippling muscles in Moses’ forearms fairly glistened of sweat. Like Moses, the modern turbojet engine is a highly-polished work…of the technological art, but with a much-extended gestation period and many fathers!

We recently returned from a two-week trip to New England, made possible by the marvels of modern aviation…and, specifically, the turbojet engine. Whenever I travel, I am cognizant of this monument to man’s ingenuity and dedication. Today, these engines are called upon to power countless tons of aircraft, passengers, baggage and cargo into the sky, hour after hour, trip after trip, week after week, without hesitation and without the need for frequent maintenance. Today, jet engine performance and reliability are so highly refined that travelers rarely think twice about flying over the rugged, isolated regions of polar routes in a large aircraft with only two engines.

A Bit of Historical Perspective

Jet engines were not so reliable in early aircraft. As a young boy, I recall numerous accounts of early jet fighter planes going down due to “flameouts” where the continuous fiery combustion and expelling of combustion materials out the back ceases and all thrust is lost. That problem and other major issues have long been solved. Today’s engineering efforts are focused on fuel efficiency and performance/cost factors along with quieter operation.

I also recall the public interest and excitement when the first U.S. commercial jet airliner service began – in 1959. My family lived not too far from San Francisco International Airport at the time. We could see the earliest American Airlines Boeing 707 jetliners off in the distance on final approach to the airport. It is interesting, today, to recall the fascination and excitement attendant to the advent of the commercial jet age, especially in light of today’s tendency to take it all for granted – which is a shame. I am a firm believer that when society loses its sense of wonder and perspective, it has lost something vital and precious.

The fundamental principle of physics which explains rocket and jet propulsion was first formally identified by Isaac Newton in his scientific masterpiece of 1687 – his book known as the “Principia” (See my post of Oct. 27, 2013, “The Most Important Scientific Book Ever Written: “Conceived” in a London Coffee House).

The third of Newton’s foundational “three laws of motion” states:

For every action, there exists an equal and opposite reaction

Despite this revelation and other fundamental physical principles so expertly articulated by Mr. Newton in 1687, much more physics and many new technologies were required for the first baby-steps on the long journey necessary to produce “engines” capable of powering our human desire to travel. The critical mass of required knowledge had not materialized until the nineteen-thirties when Frank Whittle, an English engineer, built the first laboratory version of a jet engine; it was operating by 1937.


 An early Whittle engine

As with so many technologies, potential military applications provided great momentum to the product development cycle of the jet engine. The first airplane to fly powered solely by a turbojet was the German Heinkel 178, in 1939. In the 1944/45 time frame of World War 2, German engineering produced the Messerschmitt 262, the first jet-powered operational aircraft.


 Messerschmitt 262

While much faster than the propeller-driven aircraft of the Allies, the planes were too few, too late, and plagued with reliability issues (including its pioneering jet engines) for it to be a decisive weapon in the war.

The die was cast by the end of the war, however; the jet engine’s rapid maturation and future domination was inevitable. One of the technologies which quickly matured out of necessity was the science of materials which dealt with the  “strength of materials” and their physical properties. The multiple internal turbine-fans spinning at very high speeds are populated with hundreds of turbine “blades.” The metallurgy to insure that these relatively small blades withstand the extreme forces and temperatures they experience requires a sophisticated metallurgical knowledge.

An interesting aside: One of the very first “textbooks” on the strength of materials was written by Galileo Galilei in 1638. The first half of Discourses on Two New Sciences is Galileo’s pioneering analysis of material strength and reliability – one of the “two new sciences.” The second half consists of his milestone revelations on the developing science of motion physics. The latter work qualifies this book as one of the most important science books ever published, one tier below Newton’s Principia of 1687 – like all other books except Darwin’s On the Origin of Species.

   IMG_1287   IMG_1291

The next time you are at an airport, you might make it a point to observe jet aircraft which pull into a gate, power down, and sit there awaiting the next flight. The engine turbine fans can be seen still spinning 45 minutes after power-down, thanks to the superb, ultra low-friction ball-bearing designs which support the rotor shafts. You might notice also a “curly-cue” spiral painted on the front of the fan assembly just inside the engine cowl. They are there to provide easy visual indication that an engine is powered-up and turning at very high RPM. The tremendous appetite of these engines for air creates enough suction at the front-end to actually ingest ground crew members who get too close. This has, in fact, happened many times over the decades. Like the whirling propellers on older aircraft, jet engine intakes pose a deadly hazard to the folks who work around them.

Engine manufacturers such as General Electric and the U.K.’s  Rolls-Royce have learned enough of nature’s secrets to manufacture this product with an almost inconceivable reliability and performance capability. There is one aspect of nature which has proven stubborn to control and deal with, however.

Modern Jet Engines are NOT for the Birds!

The greatest enemy of the jet engine appears to be …birds! Our science and engineering capabilities have not figured out how to prevent the ingestion of our fine feathered friends into the compressor blades of these engines; it happens all too often. Do you recall Captain “Sully” Sullenberger and his short trip into the Hudson River minutes after takeoff from LaGuardia in New York? No engine is tough enough to digest a large bird and spin merrily along as if nothing happened. Oh well, even Moses has always been susceptible to “chipping” if not handled carefully.

One final comment about the similarities drawn between Michelangelo’s Moses and the highly developed modern jet engine: I am certain that jet engine technology will continue to evolve and that the end-product will improve even beyond today’s high standard. I am not sure there will be anyone coming along anytime soon who will improve upon Michelangelo’s “design!”





2 thoughts on “Jet Engines and Michelangelo’s “Moses”

  1. Brings back memories. I recall Dad pouring over a book titled Strength of Materials for his engineering work at United. Bernini also produced jet engine equivalent sculptures. Either of these masters would be tough, if not impossible, to improve upon.

    • Hi Karen! I have that very textbook of Dad’s, “Strength of Materials,” that you refer to. It is one of a number of his books that I decided to keep. I agree: Bernini the Second is not likely to materialize any time soon!

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