Henry Petroski
Any design, whether it's for a ship or an airplane, must be done in anticipation of potential failures.Collection: Design
Indeed, an engineer designing a structure is not unlike an artist painting one. Both start with nothing but talent, experience, and inspiration. The fresh piece of paper on the drawing board is as blank as the newly stretched piece of canvas.Collection: Experience
Case studies of failure should be made a part of the vocabulary of every engineer so that he or she can recall or recite them when something in a new design or design process is suggestive of what went wrong in the case study.Collection: Design
Engineering is achieving function while avoiding failure.Collection: Failure
Relying on nothing but scientific knowledge to produce an engineering solution is to invite frustration at best and failure at worst.Collection: Failure
Science is about knowing; engineering is about doing.Collection: Science
I have always been fascinated by the way things work and how they came to take the form that they did. Writing about these things satisfies my curiosity about the made world while at the same time giving me an opportunity to design a new explanation for the processes that shape it.Collection: Design
A common misconception about how things such as space shuttles come to be is that engineers simply apply the theories and equations of science. But this cannot be done until the new thing-to-be is conceived in the engineer's mind's eye. Rather than following from science, engineered things lead it.Collection: Science
Successful design is not the achievement of perfection but the minimization and accommodation of imperfection.Collection: Design
All conventional wisdom has an element of truth to it, but good design requires more than an element of truth - it requires an ensemble of correct assumptions and valid calculations.Collection: Design
Failure is central to engineering. Every single calculation that an engineer makes is a failure calculation. Successful engineering is all about understanding how things break or fail.Collection: Failure
As engineers, we were going to be in a position to change the world - not just study it.Collection: Change
I employ case studies of failure into my courses, emphasizing that they teach us much more than studies of success. It is not that success stories cannot serve as models of good design or as exemplars of creative engineering. They can do that, but they cannot teach us how close to failure they are.Collection: Design
Too much redesign has to do more with fad and fashion than with fitness and function. It is change for the sake of change. Such redesign is not only unnecessary, it is all too often also retrogressive, leading to things that work less effectively than those they were designed to replace.Collection: Fitness
There's so much written about the Titanic, and it's hard to separate what's fact and what's fiction. My understanding is that the way the Titanic was designed, the emphasis was placed on surviving a head-on collision.
I emphasize that virtually every engineering calculation is ultimately a failure calculation, because without a failure criterion against which to measure the calculated result, it is a meaningless number.
Many new technologies come with a promise to change the world, but the world refuses to cooperate.
Luxury, not necessity, is the mother of invention. Every artifact is somewhat wanting in its function, and that is what drives its evolution.
Failures are much more dramatic than successes, and people like drama. I think this is why automobile races draw such crowds. People expect spectacular crashes, which we tend to find more interesting than cars just racing around the track. The same is true of bridges, buildings, or any structure or machine.
My first book, 'To Engineer Is Human,' was prompted by nonengineer friends asking me why so many technological accidents and failures were occurring. If engineers knew what they were doing, why did bridges and buildings fall down? It was a question that I had often asked myself, and I had no easy answer.
Typically, highway bridges have about 50 years. But over in England, they have iron bridges approaching 250 years. In France, there are Roman aqueducts that are approaching 2,000 years old. So a bridge can last a very long time if it's built properly in the first place and then maintained properly.
Successful engineering is all about understanding how things break or fail.
As long as there are things to wonder about, there are stories to be written about them. That makes me happy, because writing about things seems to be my thing.
The paradox is that when we model future designs on past successes, we are inviting failure down the line; when we take into account past failures and anticipate potential new ways in which failure can occur, we are more likely to produce successful designs.
I relax by looking at things and reading about things. Even the simplest thing can reveal a great deal about the world around us. It relaxes me greatly to sit back with my feet up and look around my study at the everyday things that surround me.
I was always told that I was good in mathematics, and I guess my grades and standardized test scores supported that. My worst subjects were those that generally involved a lot of reading - English and history. So, having good test scores in math and mediocre ones in reading, I was naturally advised to major in engineering in college.
I'm a firm believer that no matter how small an object is, you can find interesting things out about it and its history.
Read and write with a sensitive ear. The craft of writing is very important. Practice the craft.
We can't simply blame the engineers when things go wrong because, no matter how well they plan, things don't always go according to plan.
We call the fates of the Titanic and the Concordia - as well as those of the space shuttles Challenger and Columbia - 'accidents.' Foreseeing such undesirable events is what engineers are expected to do. However, design trade-offs leave technological systems open to failings once predicted, but later forgotten.
Companies selling a product play down its vulnerability and emphasize its robustness. But only after technology leaves the dock is it really tested. For human operators in control of a supposedly infallible system, complacency and overconfidence can take over, and caution may be thrown to the wind.
Everything we do is designed, whether we're producing a magazine, a website, or a bridge. Design is really the creative invention that designs everything.
You can almost say that a design error is a human error because, after all, it's we humans who do the designing.
For as long as I can remember, I have been fascinated by things large and small. I wanted to know what made my watch tick, my radio play, and my house stand. I wanted to know who invented the bottle cap and who designed the bridge. I guess from early on I wanted to be an engineer.
An over-reliance on past successes is a sure blueprint for future failures.
The definition of 'safe' is not strictly an engineering term; it's a societal term. Does it mean absolutely no loss of life? Does it mean absolutely no contamination with radiation? What exactly does 'safe' mean?
If I could go upstairs and write every day, I would be happy. I don't need recreation.
It has been said, by engineers themselves, that given enough money, they can accomplish virtually anything: send men to the moon, dig a tunnel under the English Channel. There's no reason they couldn't likewise devise ways to protect infrastructure from the worst hurricanes, earthquakes and other calamities, natural and manmade.
Although engineers want always to make everything better, they cannot make anything perfect. This basic characteristic flaw of the products of the profession's practitioners is what drives change and makes achievement a process rather than simply a goal.
It is really want, rather than need, that drives the process of technological evolution.
No design, no matter how common or seemingly insignificant, is without its adamant critics as well as its ardent admirers.
Because every design must satisfy competing objectives, there necessarily has to be compromise among, if not the complete exclusion of, some of those objectives, in order to meet what are considered the more important of them.
Design is nothing if not decision making.
The space shuttle was designed, at least in part, to broaden our knowledge of the universe. To scientists, the vehicle was a tool; to engineers, it was their creation.
Because they are so humbled by their creations, engineers are naturally conservative in their expectations of technology. They know that the perfect system is the stuff of science fiction, not of engineering fact, and so everything must be treated with respect.
The same aspirations to celebrate and uplift the spirit that drove the Egyptians to build the pyramids are still driving us. The things we're doing differ only in magnitude.
Many of the familiar little things that we use every day have typically evolved over a period of time to a state of familiarity. They balance form and function, elegance and economy, success and failure in ways that are not only acceptable, but also admirable.
It seems to be a law of design that for every advantage introduced through redesign, there is an accompanying unintended disadvantage.
Betting on the success of innovative technologies in the marketplace can carry all the uncertainty and risk that betting on the next card in the deck does at a blackjack table in Las Vegas. There is a factor of randomness that must be factored in, but precisely how to do so is anyone's guess.
The most amazing achievement of the computer software industry is its continuing cancellation of the steady and staggering gains made by the computer hardware industry.Collection: Technology