I bought this book to read while on jury duty. Three months later I had read and enjoyed this book many times.

NA

I took this book on understanding about engineering. Petroski explains engineering failures with stories from the previous century. He says failure helps to advance engineering knowledge. He stresses on learning from them especially in engineering.

I liked how he used a Poet crafting a poetry with an Engineer. Both conceive in their mind and perfect it, yet they know they cannot make it perfect. His example of, "Failure by fatigue" by using paper clip was thought-provoking. A Great book and quick read. Absolute certainty is not possible in structural or any types of engineering.

When railways were introduced; Writers and Poets were concerned about how it was impacting society. They made fun of failures of engineering. This seems to run parallel with our own lives in our age.

Something that I can take away from the book is looking into a lot of failures and learning from it.
Overall, I would recommend this book to any layman who is interested in Engineering, failures.

Deus Vult,
Gottfried ( )

Great book for a layman. Easy to understand and get into. ( )

To Engineer Is Human by Henry Petroski

The subtitle of this 1985 book--The Role of Failure in Successful Design--establishes the theme of the book.

In his introduction, Petroski, a professor of civil engineering at Duke, writes:

I believe that the concept of failure…is central to understanding engineering, for engineering design has as its first and foremost objective the obviation of failure. Thus, colossal disasters that do occur are ultimately failures of design, but the lessons learned from those disasters can do more to advance engineering knowledge than all the successful machines and structures in the world…To understand what engineering is and what engineers do is to understand how failures can happen and how they can contribute more than successes to advance technology.

To elaborate on this statement, the author cites several famous engineering failures as case studies. What happened? What was learned? How is that new knowledge applied by engineers?

One example is the collapse of the Tacoma Narrows Bridge.

This suspension bridge linked the mainland of Washington State to its Olympic Peninsula and was built in 1940, a year after a bridge of similar design, the Bronx-Whitestone, was completed and opened to traffic. Both bridges used an unconventional stiffened-girder design that reduced the thickness of the roadway structure, giving it a slender silhouette. But even during construction, the Narrows bridge displayed frightening instability in crosswinds, even relatively mild ones. Its two-lane, half-mile-long deck would undulate and twist, quickly earning the bridge the sobriquet "Galloping Gerty." After only a few months of use, its imminent failure being obvious, it was closed and soon thereafter the deck tore completely apart. The only casualty was the bridge itself.

Petroski points out that the Bronx-Whitestone Bridge has a wider, six-lane roadway, but that it too displayed unsettling flexibility. Even as the Narrows bridge was going up, the Bronx-Whitestone was being altered with extra cables and stiffening devices. Alterations to the bridge continued into the 1980s.

The fault in the design of these bridges, writes Petroski, was that "the bridge span acted much like an airplane wing subjected to uncontrolled turbulence." At the time, the aerodynamic aspect of bridge design was not considered. It is now, of course, with designs being "tested in wind tunnels much the way new airplace designs are."

Other examples cited include the mid-flight explosions in the early 1950s that destroyed several DeHavilland Comets, the world's first commercial jet passenger aircraft (killing all on board each time); the collapse of pedestrian bridges spanning the vast lobby of the Kansas City Hyatt Regency Hotel at second, third, and fourth floor levels (killing and injuring hundreds).

The shortcoming of the book is its age. "From Slide Rule to Computer: Forgetting How It Used to Be Done" is a chapter near the book's end in which Petroski frets about problems that may stem from the computers supplanting manual computations, and in the process, lulling engineers into complacency. "{T}he engineer who employs the computer in design must still ask the crucial questions…" The lessons the book teaches are timeless, but a host of new case studies have presented themselves in the last twenty+ years.