History of Engineering: Case History of Flight
The invention of the airplane was accomplished by the accumulation of knowledge, testing, and creative engineering of a number of individuals. To first understand the invention of the airplane, what an airplane is needs to be clearly understood. In general we refer to an airplane as a heavier than air powered flying machine. Other types of airplanes would be lighter than air flying machines such as balloons and dirigibles, unpowered flying machines such as gliders, and minimally powered flying machines such as the modern demoiselles (single-person very light airplanes powered by human motion).
Lighter than air flying machines depended on balloons for lift. Balloons were first developed by competing groups, the Montgolfier brothers (paper mill owners) and the Paris Academy of Sciences. The Montgolfier brother's balloon used an open flame hot air balloon design while the Paris Academy of Science's lead physicist-engineer Jacques Alexandre Cesar Charles' balloon used hydrogen gas. Interestingly, the Montgolfier's theory of why their balloon flew was completely wrong, even a little comical given our modern understanding. This theme of successful design yet lack of understanding of why the design is a success repeats itself in engineering.
For a small period of time balloons, charlières and montgolfières, as a method of transportation was very popular. However the fashion faded relatively fast given that there was little practical purposes to them. Eventually powered balloons would be developed but control was still an issue. For any reasonable purpose the flying machine must go from one place to another in a controllable manner.
The Brazilian Alberto Santos-Dumont developed the first true lighter than air powered flying machine giving his cigar-shaped dirigibles a highly effective control system for his rudder and elevator. He rounded the Eiffel tower on October 19, 1901. Santos-Dumont flew the first true-controllable airplane inspiring many others to continue their work in heavier than air flight.
Of crucial design in this airplane was the automobile-like engine which Santos-Dumont had to redesign to allow for air flight with the any possible inclinations. Engine design was crucial to all successful powered airplane flights whether heavier or lighter than air. Many of these designs could only have been manufactured at the time airplanes started to take the skies.
Heavier than air machines unlike lighter than air machines needed to achieve lift using some form of wing like a bird. Studies of birds were used to design the first wings. Detailed work by Sir George Cayley of England, lead to the first flight of man, possibly one of Cayley's servant, in a heavier than air unpowered flying machine in 1853.
His work lead to the design of Otto Lilienthal's glider that formed the basis of Samuel Pierpont Langley's, the Wright brother's, and the Aerial Experiment Association's airplanes. With the glider's development and aerial engines that were used in lighter than air flying machines, the only problem left to solve was the stability problem that heavier than air machines all seem to have. Cayley had made some progress using a rudder to enhance stability, but for powered machines the rudder was not sufficient.
The head of the Smithsonian Institute an astronomer named Samuel Langley, who had experiment with heavier than air flying machines since 1889, developed a rudimentary aileron called a dihedral wing to alleviate the stability problem. While some worked in secret to develop their airplane, Langley was widely published and undoubtedly instrumental in others development of the airplane. Langley's planes never flew and he was ridiculed for his failures. However is work which included confirmation of previous work before him made possible the continued progress towards a sustainable useful heavier than air powered flight.
The Wright brother's developed the warp wing idea to alleviate the stability problem. This worked well but was very difficult to control and their planes were very dangerous to fly. Wilbur Wright seemed to have the uncanny ability to control their planes and flew from a rail the first heavier than air powered flight on December 17, 1903. However this was not like any plane we know today.
It was up to the AEA whose members consisted of Glenn Curtiss, Alexander Graham Bell, Frederick Baldwin, Thomas E. Selfridge, and Douglas McCurdy to fly the first plane as we understand it today. They solved the stability problem by using ailerons which all modern planes use in some fashion. Glenn Curtiss flew their first successful plane, the June Bug, in 1908 and continued developing innovations that enabled him to built a successful business that would eventually absorb the Wright brother's business. This plane, unlike the Wright brothers' plane, took off using wheels like modern planes. The Wright brothers' plane took off using a rail and catapult system, though some French pilots licensed by the Wright brothers did fit wheels to the aircraft. The AEA planes (the most famous being the June Bug and Silver Dart) had superior stability over the Wright brothers' planes and other advantages, such as wheels for take-off and landing and a perfected engine. With their successful flights and the death of one of their members in a Wright brothers' plane, the AEA disbanded though Glenn Curtiss continued to produce innovative airplanes, using the designs of the AEA, through the first licensed US aircraft manufacturer, the Curtiss Company. In 1910 Glenn Curtiss broke the Wright brothers' distance record by flying from Albany, New York to New York City along the Hudson river, 150 miles, proving to the US the viability of airplanes and establishing his company as well. The Curtiss company produced some of the finest aircrafts until superseded by other companies that had new innovation such as Douglas (DC-3) and Lockheed (U-2).
Unfortunately, lawsuits between the Wright brothers and Glenn Curtiss stifled progress on airplanes in the United States for years until the government demanded an end to the petty bickering because of World War I. Airplanes were crucial to the war effort and Europe had made considerable strides in this technology while the United States was embroiled in legal limbo. The lawsuits contented that warped wings and ailerons were the same idea. Each were initially patented separately, but the courts disputed this with no clear resolution.
Today it would be hard to make the contention that the two technologies are the same as the ideas are sufficiently different as to be considered separate distinct ideas. Patent laws were substantially different 100 years ago, however. We might consider it fortunate that the government stepped in to allow progress of the airplane to continue despite the patent laws.
The local National Air & Space Museum has some interesting information that follows along this lecture (with a bias towards the Wright Brothers as required by their attorneys). Here are some pictures from that exhibit: First Flight Pictures.
To read more I suggest:
Wings of Madness: Alberto Santos-Dumont and the Invention of Flight, Paul Hoffman, Theia, New York (2003)
Progress in Flying Machines, Octave Chanute, Dover Publications, New York (1997) -- Originally published in 1894
Unlocking the Sky, Seth Shulman, Perennial (HarperCollins), New York (2002)
Rocket Man, David A. Clary, Theia, New York (2003)
How We Invented the Airplane, Orville Wright, Dover Publications, New York(1988) -- Note that most books on the Wright brothers' planes are derived from this book, and are largely unoriginal with no independent research; don't waste your money on those books. The Wikipedia page suffers from this as well. Do real research...don't follow Wikipedia.
Flight Around Eiffel Tower - October 19, 1901: Santos-Dumont (rudder and elevator)
First flight heavier than air machine - December 17, 1903: Wright Brothers (rudder, elevator, and warp-wing)
First public flight of heavier than air machine - October 23, 1906: Santos-Dumont - This was likely less stable then the Wright Brothers (this had ailerons, but the wings were problematic)
First public flight of heavier than air machine in North America - March 12, 1908: Aerial Experiment Association
First flight of air machine to win first Aeronautical prize in the United States: the June Bug - May 21, 1908: Aerial Experiment Association - This was stable and worked well. (This had ailerons with good wings).