Samuel Pierpont Langley, American Scientist and Aviator Pioneer

Samuel Pierpont Langley was one of the lesser known pioneers in aviation. Though his formal education ended after completing high school, Langley was well read, reading extensively in science, literature and history. He popularized scientific knowledge by writing magazine articles.

Using his knowledge of aerodynamics, Langley built a number of elastic-powered models. In 1896 (the same year Otto Lilienthal died), Langley was successful in flying several small-scale unmanned, steam-powered aircrafts launched from the top of a houseboat on the Potomac River.

In 1898, at the request of the US government Langley started to build a piloted machine. The aircraft did not fly because the launching apparatus failed.

Name: Samuel Pierpont Langley
Birth Date: August 1834 – February 1906
Job Functions: Scientist, Aviator Pioneer, Professor of Physics and Astronomy
Fields: Astrophysics, Aviation
Known For: Bolometer

Though Samuel Pierpont Langley’s formal education ended when he completed high school, he was a voracious reader and studied various branches of science. He worked as an engineer and architect and held positions such as head of an observatory at the Naval Academy in Annapolis, Maryland, Director of the Allegheny Observatory in Pittsburgh, and Secretary of the Smithsonian Institution in Washington, D.C.

An inventor in his own right, Langley invented and sold a technique to provide standard time signals to railroads. Between 1879 and 1881, he also invented the bolometer, an instrument for measuring tiny quantities of heat. “The superior measurements by means of the bolometer, the newly discovered extent of the solar spectrum, and the new results for selective absorption of the earth’s atmosphere were significant contributions to the study of the sun and its effect on earth.”

In 1887, while Langley was at the Allegheny Observatory, he started a series of aerodynamics experiments. He continued his investigation into the possibility of piloted flight after his appointment as Secretary of the Smithsonian.

“He studied the lift and drift of moving plane surfaces on a sophisticated scientific basis. Experimenting with small models propelled by elastic strips, he worked out the mathematics of the problem. His contributions to aviation rest not only on the knowledge he acquired and shared with others upon his successful distance flight of power-driven models, but also upon the dignity he brought, as a man of sound scientific reputation.”

In 1896, Langley successfully flew a 14-foot steam-powered aircraft model for 3,000 feet over the Potomac River. He repeated his experiment, and this time, the model flew 4,200 feet. The novelty of the situation was that these were the first sustained free flights of powered heavier-than-air machines. Two years later, the US War Department awarded Langley a grant for $50,000 to continue his experiments to achieve piloted flights.

Langley built a full-sized aircraft with a 53-horsepower gasoline engine. He made two highly publicized events at flying and failed both times – the craft fell into the water shortly after takeoff. It’s believed that there were defects to the launching device. It’s worthy to note that in 1914, Glenn Curtiss successfully flew a modified version of Langley’s airplane.

What Did Langley Do Wrong?

Langley’s aircraft had excellent propulsion and adequate aerodynamics, but the structural design was poor. The Wright Brothers are credited for inventing the airplane, and what they did differently from Langley, was they first mastered the art of fly using unstable gliders before they added power, and that made the difference to their success. The development of flight followed the trajectory of the Wright Brothers and not Langley. The Wright Brothers also built a wind tunnel where they could test their flying devices in a more controlled environment.

Have you read?

The Wright Brothers and Mastering the Fundamentals

Wise People: Wright Brothers, Inventors of the Airplane

The Early History of the Airplane by Orville and Wilbur Wright

Otto Lilienthal, King of Gliders

Steps to Success

Langley was a voracious reader and read several branches of science to elf-educate.
He was a keen observer, and experimented a lot.
Langley shared his research findings with others to move the field forward.
He gave legitimacy to the to the early aviation field because he was a respected scientist.

Why Samuel Pierpont Langley Contribution Matters

Samuels Pierpont Langley may not have contributed that much to piloted flight, but Max Planck’s interpolated radiation law were based in part on bolometer measurements. Langley invented the bolometer.

Experiments in Aerodynamics, Volume 27, issue 1 The New Astronomy The Bolometer Langley Memoir on Mechanical Flight