Louis Charles Breguet (2 January 1880 in Paris – 4 May 1955 in Saint-Germain-en-Laye, France) was a French aircraft designer and builder, one of the early aviation pioneers.
Louis Charles Breguet was the grandson of Louis-Francois-Clement Breguet, and great-great-grandson of the famous horologist Abraham-Louis Breguet.
In 1902, Louis married Nelly Girardet, the daughter of painter Eugène Girardet. They had five children together.
In 1905, with his brother Jacques, and under the guidance of Charles Richet, he began work on a gyroplane (the forerunner of the helicopter) with flexible wings. On 29 September 1907, it achieved the first ascent of a vertical-flight aircraft with a pilot, albeit only to a height of 0.6 metres (2.0 ft). It was also not a free flight, as four men were used to steady the structure.
He built his first fixed-wing aircraft, the Breguet Type I, in 1909, flying it successfully before crashing it at the Grande Semaine d'Aviation held at Reims. In 1911, he founded the Société anonyme des ateliers d’aviation Louis Breguet. In 1912, Breguet constructed his first hydroplane.
He is especially known for his development of reconnaissance aircraft used by the French in World War I and through the 1920s. One of the pioneers in the construction of metal aircraft, the Breguet 14 single-engined day bomber, perhaps one of the most widely used French warplanes of its time, had an airframe constructed almost entirely of aluminium structural members. As well as the French, sixteen squadrons of the American Expeditionary Force also used it. A plane of this type has a major role in the plot of the 1927 thriller So Disdained by Nevil Shute.