Text and Its Tenses

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                The question has often been asked why the Wright brothers were able to succeed in an effort in which so many others had failed. Many explanations have been offered, but three reasons are most often cited. First, they were a team. Both men worked well together, read the same books, located and shared information, talked incessantly about the possibility of manned flight, and served as a consistent source of inspiration and encouragement to each other. Quite simply, two geniuses are better than one.

                They were also both glider pilots. Unlike some other engineers who experimented with the theories of flight, Orville and Wilbur Wright experienced the practical side of their work by building and flying in kites and gliders. Each craft was slightly better than the last, incorporating in it the knowledge that they had gained from previous failures. They had realized from their experiments that the most serious problem in manned flight would be stabilizing and maneuvering the aircraft once it was airborne. While others concentrated their efforts on the problem of achieving lift for take-off, the Wright brothers focused on developing a three-axis control for their aircraft. By the time that the brothers started to build an airplane, they were already among the best glider pilots in the world, and they knew the problems of flying first hand.

                In addition, the Wright brothers had designed more effective wings for the airplane than had been previously engineered. Using a wind tunnel, they tested more than two hundred different wing designs, recording the effects of slight variations in shape on the pressure of air on the wings. The data from these experiments allowed the Wright brothers to construct a superior wing for their craft.

                In spite of all these advantages, however, the Wright brothers might not have succeeded had they not been born at precisely the opportune moment in history. Attempts to achieve manned flight in the early nineteenth century were doomed because the steam engines that powered the aircrafts were too heavy in proportion to the power that they produced. But by the end of the nineteenth century, when the brothers were experimenting with the engineering options, a relatively light internal combustion engine had already been invented, and they were able to bring the ratio of weight to power within acceptable limits for flight.