Airplanes that Transformed Aviation
Sixteen historic designs that changed the game.
- By Richard P. Hallion
- Air & Space magazine, May 2008
NASM (SI 78-14972)
(Page 2 of 3)
To comply with post-World War I restrictions, the Allies ordered it destroyed in November 1922, a sad loss. But though never itself produced, many of its features—stressed skin, torsion-box spar, leading edge engines, and gracefully tapered wing—became standard elements of long-range aircraft, as did its general configuration.
A. K. Rohrbach, “Das 1000-PS Verkehrsflugzeug der Zeppelin-Werke, Staaken,” Zeitschrift für Flugtechnik und Motorluftschiffahrt, vol. 12, no. 1 (15 Jan. 1921); E. Offermann, W. G. Noack, and A. R. Weyl, Riesenflugzeuge, a volume in the Handbuch der Flugzeugkunde series (Richard Carl Schmidt & Co., 1927).
7. Bäumer Sausewind
Paul Bäumer was a master of reinvention: a pre-war dental assistant turned wartime fighter ace, a postwar dentist, and then an airplane manufacturer. His streamlined, two-place Sausewind (“Rushing Wind”), designed to compete in a 1925 light-aircraft race, anticipated the definitive streamlined form of the propeller-driven airplane. Designed by Walter Gunter, who, together with his brother Siegfried, possessed a rare genius, the airplane had a beautiful wooden elliptical wing joined to a smooth, plywood monocoque fuselage, with similar elliptical vertical and horizontal tail surfaces. Bäumer died in a 1927 accident flying another company’s airplane, and the Gunters moved to Heinkel. There, they used the Sausewind's aerodynamic shape for the Heinkel He 70 Blitz high-speed transport. Beverly Shenstone, who worked with Reginald Mitchell at Vickers Supermarine and was responsible for the Spitfire’s aerodynamic design, recalled that he “used the He 70 as an aerodynamic target when calculating the Spitfire performance,” praising its “brilliance and style.” It was the ultimate compliment one could pay the Sausewind, which flew with a perfect elliptical wing a full decade before Mitchell’s legendary fighter.
Georg Madelung, “Der Otto Lilienthal Wettbewerb,” in Wilhelm Hoff (editor), Jahrbuch 1926 der Deutschen Versuchsanstalt für Luftfahrt, e.v., Berlin-Adlershof (DVL, 1926);
Richard von Mises, “Mathematical Problems in Aviation,” The American Mathematical Monthly, vol. 47, no. 10 (Dec. 1940);
H. Dieter Köhler, Ernst Heinkel—Pionier der Schnellflugzeuge (Bernard & Graefe, 1999);
B.S. Shenstone, “Germany’s Turbulent Pioneer,” The Aeroplane (7 Feb. 1958).
8. Dornier Wal
The name Dornier is forever associated with a series of Second World War bombers and with the awkward-looking Do X flying boat of 1929, which became the first transatlantic airliner. But behind them was the airplane that company founder Claude Dornier credited with saving his firm: the Dornier Wal (“Whale”). “The Wal made Dornier,” he once remarked, and besides, it made oceanic flying boat operations practical. Blending Duralumin (an aluminum alloy) construction techniques derived from Dornier’s years at Zeppelin with rugged ship-building practice, the twin-engine Dornier Wal, which first flew in 1922, embodied significant design refinement, including use of a high, semi-cantilever monoplane wing and broad stabilizing sponsons in place of higher-drag and more complex wingtip floats. Thus the Wal anticipated the design of the most successful large passenger-carrying seaplanes, aircraft such as the Martin M-130 (the famed “China Clipper”) and the Boeing 314. But it was a notable international success itself. More than 300 were built in Italy, Netherlands, Japan, Spain, and Russia, for both military and civil purposes, using a variety of engines. It established a number of world records for speed and payload, spanned the Atlantic and circled the globe, and gave rise to more powerful three- and four-engine streamlined successors. It was a favorite mount for explorers: Indeed, the Wal was the first aircraft to significantly influence the study of Earth, its polar regions, and the environment in general.
Roald Amundsen and Lincoln Ellsworth, Air Pioneering in the Arctic (National Americana Society, 1929);
M. Michael van der Mey, Dornier Wal: “A Light Coming Over the Sea” (LoGisma editore, 2005).
9. Douglas DC-1
The Douglas DC-1, created by a team led by Arthur E. Raymond, may be said to be the first scientifically designed American airplane. It blended the research and experience of industry, federal research laboratories such as the National Advisory Committee for Aeronautics (NACA), and academic centers, specifically the Guggenheim Aeronautical Laboratory of the California Institute of Technology, where its shape was refined by extensive wind tunnel testing. The aircraft utilized the all-metal, multi-cell structure John Knudsen Northrop had developed previously for his Alpha of 1930 (when, ironically, he was partnered with Boeing). The 12-passenger, twin-engine DC-1 blended advanced aerodynamics (typified by turbulence-reducing wing-fuselage fillets, payload-enhancing wing flaps, and refined engine cowling placement); higher-strength aluminum alloys; a retractable landing gear; controllable pitch propellers; and a lightweight monocoque fuselage structure. Its superiority over the rival Boeing 247 was evident from the outset: Little more than a week after its first flight, TWA chief pilot D.W. “Tommy” Tomlinson, one of the most experienced test pilots of the time, reported jubilantly to company president Richard W. Robbins: “I think we have a fine airplane.” Indeed: It spawned the DC-2 and DC-3 and an entire “DC generation,” its shape as symbolic of 1930s Modernist aeronautics as Boeing’s swept-wing 707 was of the 1950s, or Concorde’s ogival double-delta was of the 1970s.
D.W. Tomlinson to R.W. Robbins, 9 July 1933, Box 124–517, Charles A. Lindbergh Papers, Yale University Library;
D.W. Douglas, “The Douglas DC-1 Airliner,” Aero Digest, vol. 23, no. 4 (Oct. 1933);
Douglas J. Ingells, The Plane That Changed the World (Aero Publishers, 1966);
Peter W. Brooks, The Modern Airliner (Putnam, 1961).
10. Lockheed XC-35
Lockheed’s XC-35 was the world’s first aircraft specifically constructed with a pressurized passenger cabin and, as aerospace medical historian Douglas Robinson notes, is “the true ancestor of all modern pressurized airliners.” Credit for the cabin goes to structures experts Major Carl Greene and John Younger, both of whom worked for the Air Corps Engineering Division at Wright Field (now Wright-Patterson Air Force Base) in Ohio. They worked with Lockheed to redesign the fuselage of the Lockheed 10A Electra, adding two turbosuperchargers to its radial engines both to improve altitude performance and to feed air to the cabin. Designated XC-35 and delivered to Wright Field in May 1937, it began flight testing in July, flying up to 33,000 feet while maintaining a cabin pressure of 9.5 pounds per square inch. The XC-35 underwent an extensive series of high-altitude flight tests, proving the practicability of pressurizing the cabin. So confident were Army Air Corps leaders of its safety that they allowed it to be used as an executive transport for Louis Johnson, the assistant secretary of war. The XC-35 won the 1937 Collier Trophy for the Air Corps. But more significantly, it pointed the way for pressurized bombers and transports, the first of which were Boeing’s B-29 and Model 307.
National Museum of the U.S. Air Force XC-35 Data Sheet;
XC-35 Curatorial File, National Air and Space Museum;
Douglas Robinson, The Dangerous Sky (University of Washington Press, 1973).
11. Gloster E.28/39
Two great revolutions transformed aeronautics at mid-century: the invention of the jet engine, and the development of high-speed aerodynamic theory enabling the development of transonic and supersonic aircraft. Though the Gloster E.28/39 was not the first jet airplane to fly—that distinction goes to the Heinkel He 178, flown in August 1939—it was the most influential of the first jet airplanes flown, as its engine had a far greater impact on turbojet engine development than the engine flown in the He 178. While the He 178's engine proved a dead end technically (as Germany emphasized axial, not centrifugal, compressors), the Whittle engine used in the E.28/39 influenced international gas turbine design—being, for example, the first jet engine used by America's own first jet aircraft, the Bell XP-59A of 1942. The X.28/39 was strictly a research aircraft, intended to verify the merits of the gas turbine, using an engine developed by Royal Air Force Wing Commander Frank Whittle. On May 15, 1941, it became the first British turbojet aircraft to fly. In April 1941, U.S. Army Air Corps Major General Henry H. “Hap” Arnold visited England and became aware of Gloster and Whittle’s work. He immediately arranged for importation of Whittle engine technology to the United States, and it formed the basis for the first U.S. jet airplane, the Bell XP-59A Airacomet. The E.28/39 demonstrated the practicality of a turbojet-powered airplane, and from this demonstration sprang Gloster’s next jet project, the F.9/40, better known to history as the Meteor. For its influence on British and U.S. aircraft design, and through that, upon Soviet, Chinese, and French design, the E.28/39 is the most significant of early jet test beds.
William Green, The Jet Aircraft of the World (Hanover House, 1957);
Andrew Nahum, Frank Whittle: Invention of the Jet (Icon Books, 2004);
Walter J. Boyne and Donald S. Lopez, The Jet Age (Smithsonian, 1979).
12. North American XP-86 Sabre
The North American F-86 Sabre is justly famous as America’s first swept-wing jet fighter, triumphing over the MiG-15 in swirling dogfights over the Yalu River during the Korean War. The Sabre was the world’s first aircraft designed with a swept wing deliberately to attain a high-speed advantage. The first to fly was the prototype XP-86, in October 1947. The low-speed, swept wing, intended to impart inherent longitudinal stability, had appeared before the First World War. The advantages of the high-speed swept wing were to delay transonic drag rise and shock wave formation and, if sharply swept, to remain within the subsonic air flow contained within the shock cone that forms around a supersonic airplane. These advantages were first enunciated by a young German aerodynamicist, Adolf Busemann, in an Italian conference in 1935. Ignored at the time by all but Germany, the high-speed, swept wing was independently rediscovered by Robert Jones, working at the NACA’s Langley laboratory in Virginia in 1944. Though Germany had many swept-wing projects on the drawing boards, it did not field a true swept-wing aircraft. (The Me 262 was, like the Douglas DC-3, basically a straight-wing aircraft with pronounced leading edge taper, and the rocket-powered Me 163, which used a swept wing for both stability and high-speed flight, had such abysmal flying qualities that it could not take advantage of its wings’ sweep). The XP-86 gave to the world the first truly transonic swept wing, the iconic shape of the Jet Age.
W. Green, The Jet Aircraft of the World;
Adolf Busemann, “Aerodynamische Auftrieb bei Überschallgeschwindigkeit,” Luftfahrtforschung, vol. 12, no. 6 (3 Oct. 1935);
Robert T. Jones, “Wing Planforms for High-Speed Flight,” NACA Technical Note 1033 (1946) [23 June 1945];
Richard P. Hallion, “Lippisch, Gluhareff, and Jones: The Emergence of the Delta Planform and the Origins of the Sweptwing in the United States,” Aerospace Historian, vol. 26, no. 1 (March 1979).
13. Bell XS-1
Conceived to make up for shortfalls in wind tunnel design (existing tunnels could not accurately test models at transonic speeds), the rocket-powered Bell XS-1 became the world’s first supersonic airplane, demonstrating the transonic benefits of a thin, low-aspect-ratio wing (essentially, one that is short and broad, like the wing of a Piper Cherokee) coupled with a streamlined, bullet-shaped body and an adjustable horizontal stabilizer for greater longitudinal (pitch) control efficiency as an airplane approached the speed of sound. It likewise validated the concept of the fully instrumented research airplane that used the sky essentially as a laboratory. Remembered best for its most famous flight—to Mach 1.06 (700 mph) at 43,000 feet, flown by Charles E. “Chuck” Yeager on October 14, 1947—the XS-1 family consisted of three aircraft. Though the third was lost before powered flight testing, the first two flew for years on a variety of transonic and supersonic research missions. It was, effectively, the aircraft that opened the door through the sonic wall, giving aeronautical science its first full look at the tangles and traps of the transonic and supersonic frontier, and it led to the bigger and faster advanced X-1 family that, in the early 1950s, flew beyond Mach 2 and 90,000 feet, to the edge of the atmosphere.
U.S. Air Force, Air Force Supersonic Research Airplane XS-1 Report No. 1 (Wright-Patterson Air Force Base, 9 Jan. 1948);
Richard P. Hallion, Supersonic Flight (Macmillan/Smithsonian, 1972)
14. Boeing 367-80
With its podded engines and low-placed swept wing, Boeing’s “Dash 80” of 1954 gave to the world the generic configuration of the medium- and long-range jetliner. Though other variations would appear, such as aft-mounted engines and T-tails, the basic configuration of the jetliner was set by this remarkable design, which ensured that U.S. air transport would remain dominant in the global marketplace for another quarter-century, until challenged by the rise of Airbus. The Dash 80 was conceived to serve as two types of aircraft: a fast tanker to refuel the Strategic Air Command’s swept-wing B-47 and forthcoming B-52 bombers—also products of the Boeing stable—and a military transport. The Dash 80 is best remembered as the progenitor of the civil 707, which revolutionized air transport across the north Atlantic. From 1958 onward, thanks to the jet airliner revolution, air transportation increasingly became more democratic and less elite. The introduction of the wide-body “jumbo,” beginning with the Boeing 747, was the logical outgrowth of the 367-80 program. Today, the 367-80 is in the collection of the National Air and Space Museum, and most 707s have been reduced to coffee pots. But the direct outgrowth of the Dash 80—the KC-135 family and its own derivatives—still serve in large numbers with the Department of Defense and will do so for decades to come, at least through the first third of this century.