Suddenly the machine again began to descend and I was on the ground in about half of a minute. I remained at a height of about fifteen hundred feet for a period of five minutes without making any appreciable descent. I had ascended to a height of a little over one-half mile and was descending when, at a height of about fifteen hundred feet, I suddenly discovered that I was not able to descend further, although my motor was throttled to the limit and the machine was pointed downward as steeply as I felt it safe to descend. While making a motor flight at Montgomery, Alabama, in the Spring of 1910 I had a most unusual experience. Wright then answers DriggsвЂ™ question -В 'the most interesting or significant episode in the birth of flying at Kitty Hawk' -В before returning to the nature of flight as observed in birds: But, of course, these flights must be made in rising trends of air-a condition required by all birds for soaring flight. I see no reason why flights of several hours duration cannot be made without use of a motor. In many cases we landed at a higher point than the one from which we started. Alex Ogilvie and I continued the soaring experiments at Kitty Hawk and succeeded in making a number of flights of more than five minutes duration (the longest of which was nine and three-quarter minutes) without any loss of height at all. Attempts to imitate their flights without a motor have not been very successful, although in 19 we made a dozen or more flights in which we remained in the air for a minute with no, or scarcely any descent and in 1911. What the Wright Brothers observed during this period вЂ“ and this was a crucial element of their success вЂ“ was that birds changed the angle of the ends of their wings to make their bodies roll right or left Wright introduces that thought, which he will return to again and again:ДЄt Kitty Hawk we had the opportunity of witnessing daily the soaring flight of buzzards, fish and chicken hawks, and eagles. It was from reading accounts of Lilienthal's experiments that we became interested in this. Our early experiments at Kitty Hawk were conducted for the purpose of developing a method of maintaining equilibrium in the air and also to learn something about soaring flight. This was in the Fall and Winter of 1901-02. From this we were led into the designing and construction of a wind tunnel and apparatus to be used in the tunnel for measuring the lift and drift and the center of pressure on airfoils. Our experiments at Kitty Hawk in 1901 proved conclusively to us that the tables of air pressure then in existence were entirely unreliable. Wright begins with a description of their earliest non-motorized flights at Kitty Hawk, the вЂњlaboratory work,вЂќ he says, вЂњthat made possible the construction of our first power flyer':

In this extraordinary letter, Orville, in answering a question about what he considered 'the most interesting or significant episode in the birth of flying at Kitty Hawk,вЂќ essentially tells the story of how he and Wilbur invented the first successful airplane, and became the first men to make a motorized flight. When the bicycle-building, kite-flying Wright BrothersВ of Dayton, Ohio, took up aeronautics as a sport in 1896, they little expected they would become, by 1903, the pioneers in the science of flight.

First airplane