Airline Expansion and Innovation(1927 - 1941)

Early Aircraft Technology


Aircraft performance improved rapidly between 1911 and 1927, but aviation technology was still fairly primitive. To boost aeronautical research, the U.S. government created the NACA.

The airplane was only 15 years old when air mail service began in 1918. Airplanes were still essentially wood and cloth machines that performed inefficiently. Most were biplanes. Concerned that the United States was rapidly falling behind Europe in aeronautical technology,

Congress formed the National Advisory Committee for Aeronautics (NACA) in 1915 to supervise and direct American aeronautical research. By the end of the 1920s, the NACA's efforts were bearing fruit.


The National Advisory Committee for Aeronautics

Spurred by Smithsonian Secretary Charles D. Walcott, the NACA soon became the nation's preeminent aeronautical research organization and attracted some of the nation's most creative engineers.

Pioneering research by the NACA and its successor, the National Aeronautics and Space Administration (NASA), solved many of flight's most difficult problems and greatly improved the performance and safety of all aircraft. The NACA/NASA developed some of the most important technological innovations in air transportation. This critical research continues today.

Wind Tunnel
National Air and Space Museum Archives

Named after Samuel P. Langley, third secretary of the Smithsonian, the NACA's Langley Memorial Laboratory opened in 1917. The flight testing facility featured the first pressurized (variable density) wind tunnel. It was used to gather precise data on wing shapes.

National Air and Space Museum Archives -->

The NACA acquired a fleet of 19 aircraft to test their flight characteristics and create new design parameters. It designed equipment to measure air pressure distribution on wings and also began research on engines.

DH-4 and Tractor
National Air and Space Museum Archives

Europeans led the world in aeronautics after World War I. They developed monococque ("single shell") construction-the aircraft's skin carried most of the aerodynamic load, reducing structural weight. In Germany, Hugo Junkers patented the internally braced cantilevered wing. Adolf Rohrbach built a series of advanced all-metal aircraft, including this Zeppelin E.4/20.