Matt Col—n
Throughout the history of engineering, failed or flawed projects and designs have many times lead to disastrous ends. In Kansas City, the Hyatt Regency HotelÕs newly implemented skywalks fell because of a last minute decision to change the support design, killing 114 people and injuring almost 200 more in 19811. The Tacoma Narrows Bridge in Washington for months after it was opened undulated during moderate winds, eventually twisting itself apart in 19402. Several de Havilland Comet commercial jetsÕ pressurized cabin exploded during take-off and flight, one being destroyed on the first anniversary of jetliner service in 1953 and two more in 19543. As a result of these failures being publicly known, steps were taken to find out what caused the failure and what would need to be done to fix these problems. New measures were taken to fix similar existing structures, and from the knowledge gained from these failures, the Hyatt Regency Hotel replaced its skywalk design with a more stable single walkway4, other bridges similar to the Tacoma Narrows Bridge were retrofitted to increase their structural safety5, and the de Havilland Comet 4 was the first to start a trans-Atlantic jet passenger service6.
As seen in the cases of the Hyatt Regency Hotel, the Tacoma Narrows Bridge, and the de Havilland Comet jets, failure has been the forerunner to innovative engineering success. From this we can ask the question: Do people learn more from failures than successes?
In the book, To Engineer is Human, Petroski makes the argument that innovative successes and structural soundness are products of the knowledge gained by failure. He states that apparent success does not prove true success, for Òno matter how many examples of agreement one may collect, they do not prove the truth of the hypothesis, for it may be argued that one has not tested it in the single case where the theory may fail to agree with reality7.Ó Thus only through failure can be know how to design one step closer to true success. From his own life, he gives examples of progress through failure, such as the improvement of the Speak & Spell from using a keyboard with breakable buttons to using a buttonless keyboard8 and his endeavor with his son to create a slingshot9.
From numerous behavior studies on animals and humans, behavior scientist Edward Lee Thorndike conversely believes that people can learn more by Òaccidental successÓ rather than failure. He states in The Human Nature Club, ÒThe method of learning by the selection of successes from among a lot of acts is the most fundamental method of learning10.Ó If applied to the engineering field, the most fundamental method of learning would be from the analysis of successful designs and structures and what was done that made them successful. Too many factors can lead to failure; studying the few aspects that led to a designs success will benefit the learning party more than studying the many causes for failure.
Analysis
Based on the arguments and examples made in PetroskiÕs book, coupled with other examples and personal experience, I have found that failure is a better learning tool than success. The de Havilland Comet had seen three large failures, claiming the lives of many in the process. Even though the design Òrelied on well-established methods essentially the same as those in general use by aircraft designers11,Ó it had the unknown flaw of cabin windows developing cracks during use. However, Òthe experience with the Comets eventually improved the state of the art of aircraft design12.Ó The new model of Comets, the Comet 4, was strengthened using the knowledge gained from its failed predecessors, increasing its lifetime from thirty thousand hours to over hundreds of thousands of hours13. Additionally, the first jet to start a trans-Atlantic service was a de Havilland Comet 4, clearly proving that ÒComet failure [had] turned into Comet success14.Ó
Talking with a friend of mine about learning from failure, he informed me of some of the progresses of civil engineering that had been initiated in response to a certain structural failure. A section of a warehouse roof collapsed at Wilkins Air Force Depot in Shelby, Ohio, in 1955, originating from a shear failure. The warehouse roof was supported by reinforced concrete continuous frames, but the main longitudinal girders had little web reinforcement. In response to this failure and distress problems in some similar structures, revisions were made for the 1956 edition of the ACI Building Code, and research began on shear strength of reinforced concrete members. In 1973, the ASCE-ACI Committee 426, Shear and Diagonal Tension released ÒThe Shear Strength of Reinforced Concrete Members,Ó reviewing experimental data obtained on shear. Committee 426 also said that Òthe behavior of beams failing in shear was much better understood than the behavior of members such as columns, deep beams, and corbels, and that there was a need to develop realistic behavioral models for these members as well,Ó which could serve as a basis for Òthe future unification and simplification of design regulations.Ó From a single failure, research began and experiments were done to improve the strength of reinforced concrete, a step towards progress that would not have begun if the incident at Wilkins Air Force Depot had not showed a need for it through failure15.
As a musician, I have learned that failure is the only way to progress; if anyone can pick up a violin and play like a concert master, no one would need to practice. Practicing a piece of music is the repetition of failure, creeping closer and closer to success, and then attempting to repeat the success while minimizing the failures. I remember the hours spent teaching my roaming bow to play only in a small section next to the bridge of my violin and my sluggish left hand to accompany my impatient right hand on the piano. Only after these hours would I have climbed the steps of failure to reach a level of success.
People learn more from their failures than their successes. While traveling on the road of success leads us safely and endlessly straight, we miss the lessons to be learned from each branch of our path, lessons both joyful and painful. In general, a failure places an obstruction in our path, telling us to go a different direction. Only through meandering the labyrinth of failed designs do we reach its center where its innovative treasure is stored. From there, we can jump back onto the trodden road of success, safe and failure free, or we can follow the unbeaten path leading to the next labyrinth. Being engineers, what path should we take? As Robert Frost concurs, take the path less traveled by; it will make all the difference.
Referenced from http://psych.unn.ac.uk/pdf/thorndike.pdf