The history of aviation brims with airplanes that have represented the pinnacle of design: swift fighters, long-range bombers and transports, exciting sport biplanes, experimental airplanes that used the sky as a laboratory. Many set notable records, helped win wars, increased our mobility, trained thousands of pilots, or in any of a number of ways influenced aviation. Anyone remotely interested in the history of flight will instantly recognize the names: SPAD, Fokker Triplane, Vega, Comet Racer, Zero, Spitfire, MiG, Pitts, Starfighter, Blackbird, and Concorde, to name just a few.
But what were the transformational airplanes? The ones that changed design practice so that future aircraft of similar type were different from what had flown before?
The transformational airplane is a rarity, and surprisingly, many are not as well known as they should be. The innovations they introduce appear on subsequent designs that often become much better known. In other cases, they may be remembered for other qualities they possessed, qualities that mask or hide why they were technologically significant. A few changed not just aviation but the broader world around them; these are included in the article “10 Airplanes That Changed the World” in the June/July 2008 issue of Air & Space/Smithsonian. They are considered here, however, solely for their contribution to the art and science of flight.
The following is a very subjective list, offered as a stimulus for thought and discussion. Obviously, many other aircraft types could be nominated, and numerous lists of “also rans” are possible.
Here goes! (See the photo gallery at top right for photos of the 16 airplanes.)
(Richard P. Hallion was the Air Force Historian from 1991 to 2002, and is the author of more than a dozen books on aviation history. He currently is the Verville Fellow at the National Air and Space Museum.)
1. Wright 1905 Flyer
Not as well known as the first airplane, the 1903 Flyer, the Wright 1905 Flyer was the world’s first practical airplane. The 1903 and 1904 machines were purely experimental, laying the groundwork for three-axis control—in yaw, pitch, and roll. The 1903 Flyer had interconnected roll and yaw (wing warping and rudder). The 1905 Flyer, on the other hand, was the first airplane to have independent three-axis control.
Though it still used a catapult for launch and it still had the instability of all early Wright biplanes, the 1905 Flyer differed significantly from them. It had upright seating for its pilot and a passenger, twice the power of its predecessors, 50 percent greater speed, and much greater endurance, capable of flying for more than half an hour. In modern parlance, the 1905 Wright Flyer constituted a pre-production prototype for subsequent Wright production designs—and a template for the world’s aircraft that followed. Fittingly, visitors to the Wright Hall at Carillon Park in Dayton, Ohio, can see this remarkable airplane, magnificently restored, with the assistance of Orville Wright himself.
Further reading:
Marvin McFarland, Wright Papers (McGraw-Hill, 1953);
Wright Flyer curatorial files;
Charles Gibbs-Smith, Dictionary and Nomenclature of the First Aeroplanes (HMSO, 1966);
Kenneth Munson, Pioneer Aircraft (Macmillan, 1968).
2. Blériot XI
Louis Blériot’s unremarkable appearance masked a fine technical mind and a boldly adventurous, even courageous, personality. His Model XI is remembered for having made the first flight across the English Channel, on July 25, 1909—a feat of bravery, skill, and technology. And it had profound strategic implications: Britain’s Daily Mail newspaper proclaimed “England is no longer an island,” and indeed it wasn’t: In less than a decade, German Zeppelins and bombers would appear in its skies, marking the first Battle of Britain. But beyond all this, the Model XI established the tractor “engine in front” monoplane tradition, together with the classic tail-dragger landing gear. Larger, more powerful derivatives of the Blériot were the world’s first successful air exports, and among the first military reconnaissance and bombing airplanes to fly in actual combat. The Blériot signaled that European aviation, moribund after the death of German glider pioneer Otto Lilienthal in 1896, was back—and that the early era of unchallenged supremacy by the Wrights and Glenn Curtiss was at an end.
Further reading:
Charles Gibbs-Smith, Dictionary and Nomenclature of the First Aeroplanes (HMSO, 1966);
Kenneth Munson, Pioneer Aircraft (Macmillan, 1968);
Alfred Gollin, No Longer an Island: The Impact of Air Power on the British People and Their Government (Stanford University Press, 1989)
3. Deperdussin Monocoque
Conceived by Louis Béchéreau and Frederick Koolhoven and sponsored by Belgian silk merchant and manufacturer Armand Deperdussin, the Deperdussin Monocoque introduced the stressed-skin shell structure to aircraft design, which became a global design standard, first in wood and then in metal. This shapely machine also launched the streamlining revolution that continues to the present day. First flown in 1911, the Deperdussin Monocoque racer blended the Blériot-style monoplane approach with a much more refined form, giving it an appearance more typical of racers at the end of the 1920s than of aircraft flying less than a decade after the airplane's debut at Kitty Hawk. Thereafter it underwent steady design evolution. In September 1912, a more powerful and even smoother formed Deperdussin won the Gordon-Bennett Trophy Race in Chicago, becoming the first airplane to exceed 100 mph. It also introduced the powerful rotary engine to aircraft design. Deperdussin’s firm collapsed amid charges of fraud and embezzlement, and he went to jail. Blériot reorganized it, and Béchéreau remained its chief engineer, working with André Herbemont to design the wartime SPAD fighter—an aircraft that, festooned with struts and wires, hardly resembled the streamlined purity of its predecessor. But others did bear the resemblance—and on the other side, most notably the German Albatros, whose distinctive shark-like shape reflected Béchéreau’s pre-war design.
Further Reading:
Henri Mirguet, “Le Monocoque Deperdussin,” L’Aérophile, vol. 20, no. 18 (15 Sept. 1912);
“The 100-hp Deperdussin Racing Monoplane,” Flight, 10 Feb. 1912.
4. Sikorsky Il’ya Muromets
Igor Sikorsky had multiple careers in aviation. His flying boats made Pan American a success and ushered in the era of intercontinental aviation, and he became the greatest of helicopter manufacturers. Frustrated in his first attempts to build rotary-wing craft—his consuming passion—Sikorsky had turned to conventional aircraft design, emulating French and German design practice. In 1913 he had developed the Russkiy vitaz, the “Russian Knight,” more popularly known as Le Grand, the world’s first large multi-engine airplane. But it was its more practical and refined successor, the Il’ya Muromets (named for a legendary Russian warrior), that really established his reputation. With dual controls for a pilot and copilot, a plush cabin (with a lavatory, private suite, bed, and even balcony), and cabin heating and lighting, this large four-engine biplane anticipated all subsequent biplane bomber and transport aircraft. In June 1914, it flew from St. Petersburg to Kiev and back, and derivatives of it proved powerful and rugged wartime bombers. Indeed, the Il’ya Muromets was the first example of the “dual use” aircraft, with interdependent civil and military roles.
Further reading:
Igor I. Sikorsky, The Story of the Winged-S (Dodd, Mead, 1967 edition);
K. N. Finne, with Carl J. Bobrow and Von Hardesty, Igor Sikorsky: The Russian Years (Smithsonian Institution Press, 1987).
5. Junkers J-13 (F-13)
Little more than a decade after the Wrights first flew, Hugo Junkers reinvented the airplane. Historian Charles Gibbs-Smith writes of Junkers: “He may be fully and fairly credited with the design and construction of the first practical cantilever [internally braced] wing aeroplanes, the first practical all-metal aeroplanes, and the first low-wing monoplanes.” Junkers adopted the thick wing, which produced greater lift and enabled construction of cantilever wings. Suspicious of wooden construction, he opted for metal. Junkers’ transformational airplane was the J-13 of 1919, which, in mass production, was better known as the F-13. It had a low wing, an enclosed cabin, an all-metal structure, and a high degree of streamlining, and launched both global air transport and the era of the mass-produced, all-metal, aluminum-alloy airplane. More than 300 were delivered around the world, and it spawned a series of similar-looking descendants, culminating in 1932 in the Junkers Ju 52. By 1924, Junkers supplied fully 40 percent of the world’s transports, placing Germany at the forefront of air transport design, a position it held until dethroned by the United States in the early 1930s.
Further reading:
C. Gibbs-Smith, The Aeroplane: An Historical Survey (HMSO, 1960);
R. Blunck, Hugo Junkers: Ein Leben für Technik und Luftfahrt (Econ-Verlag GmbH, 1951 edition);
Hans-Liudger Dienel and Martin Schiefelbusch, “German Commercial Air Transport Until 1945,” in Revue belge de philologie et d’histoire, vol. 78, no. 3-4 (2000).
6. Zeppelin-Staaken (Rohrbach) E.4/20
Adolf Rohrbach narrowly missed being Germany’s Boeing or Douglas, largely because of the fate of his E.4/20. Like Junkers, Rohrbach favored thick-wing cantilever monoplanes, but unlike Junkers, who used tubes and ribs covered with corrugated sheet, Rohrbach used dural stressed skin employing a single torsion-box spar running from wingtip to wingtip, its smooth top and bottom serving as the wing’s upper and lower surfaces. Leading- and trailing-edge ribs, attached to the front and back faces of this box and covered with thin dural sheet, gave the wing its shape. His E.4/20 of 1920 was a streamlined, all-dural design powered by four engines, weighing 18,700 pounds loaded. Only large wheels and landing gear struts marred its lines, and its high-placed, tapered, cantilever wing spanned 102 feet. It had a cabin that seated up to 18, as well as a lavatory and generous mail and luggage space. At its first flight, in 1920, both its design and performance—cruising more than 130 mph at less than full power, and ranging nearly 850 miles—were a good dozen years beyond what any other airliner had attained.

After reading some of these web articles I am amazed at the technical progress made during the first 10-15 years after Wright's 1905 airplane. I think an interesting article would deal exclusively with that time frame. It's the aircraft equivalent of the first 50 years of the Columbian Exchange.
Posted by Curtis Ritchie on May 12,2008 | 05:15PM
The wingless aircraft HL-10 and M2-F2 lifting bodies designed by my father Dale Reed for NASA at Edwards AFB in 1960s and flown by young test pilots Neil Armstrong and Chuck Yeager are on my top ten list because their designs gave significant research towards building re-entry aircraft like the shuttle's design and maneuverability.
Posted by Cristy Reed Pollak on May 31,2008 | 09:33AM
I find it amazing that with all the research and development and progress implemented by Thomas Lavelle, not a single word has been found about his discoveries. After all... he did send the first weather station Tiros I into space, he did develop the Lithium Oxide canisters that cleansed the air for Apollo 13 to safely return to Earth. Those are just a couple of examples of his genius mind!... How can you just ignore his contributions?
Posted by Stephanie Hartnett on June 28,2008 | 06:17PM
Just think where we could be today and how much farther we could be if the Wright brothers spent more time designing new aircraft instead of trying to protect theirs. We could have definitely made a lot more progress in those years.
Posted by Joshua Gallaher on July 13,2008 | 11:16AM