Henri Marie Coandă (June 7, 1886 – November 25, 1972) was a Romanian inventor, aerodynamics pioneer and the builder of world's first jet powered aircraft, the Coanda-1910. He gives his name to the Coandă effect.
Born in Bucharest, Coandă was the second child of a large family. His father was General Constantin Coandă, a mathematics professor at the National School of Bridges and Roads. Coandă studied at the Petrache Poenaru Communal School in Bucharest, then (1896) at the Saint Sava National College. After three years (1899), his father, who desired a military career for him, had him transfer to the Military Lycee in Iaşi. He graduated from that institution in 1903 with the rank of sergeant major, and he continued his studies at the School of Artillery, Military, and Naval Engineering in Bucharest. Sent with an artillery regiment to Germany (1904), he enrolled in the Technische Hochschule in Charlottenburg, Berlin.
Coandă graduated as an artillery officer, but he was more interested in the technical problems of flight. In 1905, he built a missile-aeroplane for the Romanian Army. He continued his studies (1907-1908) at the Montefiore Institute in Liège, Belgium, were he met Gianni Caproni. In 1908 Coandă returned to Romania to serve as an active officer in the Second Artillery Regiment. However, his inventor's spirit did not comport well with military discipline. He solicited and obtained permission to leave the army, after which he took advantage of his renewed freedom to take a long automobile trip to Isfahan, Teheran, and Tibet. Upon his return in 1909, he travelled to Paris, where he enrolled in the newly founded École Nationale Superieure d'Ingenieurs en Construction Aéronautique (now the École Nationale Supérieure de l'Aéronautique et de l'Espace, also known as SUPAERO). One year later (1910) he graduated at the head of the first class of aeronautical engineers.
With the support of engineer Gustave Eiffel and the mathematician, politician, and aeronautical pioneer Paul Painlevé, he began experimenting the aerodynamic techniques: one of this experiments was mounting a device on a train running at 90 km/h so he could analyse the aerodynamic behavior. Another experiment used a wind tunnel with smoke and an aerodynamical balance to profile wings to be used in designing aircraft. This later led to the discovery of the aerodynamic effect now known as the Coandă effect.
In 1910, using the workshop of Gianni Caproni, he designed, built and piloted the first 'thermojet' powered aircraft, known as the Coandă-1910, which he demonstrated publicly at the second International Aeronautic Salon in Paris. The powerplant used a 4-cylinder piston engine to power a compressor, which fed two burners for thrust, instead of using a propeller. It would be nearly 30 years until the next thermojet powered aircraft, the Caproni Campini N1. At the airport of Issy-les-Moulineaux near Paris, Coandă lost control of the jet plane, which went off of the runway and caught fire. Fortunately, he escaped with just a good scare and some minor injuries to his face and hands. Around that time, Coandă abandoned his experiments due to a lack of interest and support on the part of the public and of scientific and engineering institutions.
Between 1911 and 1914, he worked as technical director of Bristol Aeroplane Company in the United Kingdom, where he designed several aeroplanes known as Bristol-Coanda aeroplanes. In 1912 one of these planes won the first prize at the International Military Aviation Contest in the UK. In 1915, he went again to France where, working during World War I for Delaunay-Belleville in Saint-Denis, he designed and built three different models of propeller aeroplane, including the Coandă-1916, with two propellers mounted close to the tail; this design was to be reprised in the "Caravelle" transport aeroplane, for which Coandă was a technical consultant.
In the years between the wars, he continued traveling and inventing; inventions included the first jet-powered sleigh, and the first de luxe aerodynamic railroad train. In 1934 he was granted a French patent related to the Coandă Effect. In 1935, he used the same principle as the basis for a hovercraft called "Aerodina Lenticulara", which was very similar in shape to the flying saucers later developed by Avro Canada before being bought by the United States Air Force and becoming a classified project.
In 1969 he returned to spend his last days in his native Romania, where he served as director of the Institute for Scientific and Technical Creation (INCREST) and in 1971 reorganized, along with professor Elie Carafoli, the Department of Aeronautical Engineering of the Polytechnic University of Bucharest, spinning it off from the Department of Mechanical Engineering.