English-born aeronautical engineer, inventor, astronomer, and explorer of the late 19th and early 20th centuries. His best-known inventions include the box kite and the rotary engine.
He apprenticed at Australia's Australasian Steam Navigation Company and later worked as an assistant astronomer at the Sydney Observatory.
Australia's Qantas airline named one of its aircraft in Hargrave's honor.
He grew up in both England and Australia. His father, John Fletcher Hargrave, held office as Attorney General of New South Wales, Australia.
His work inspired fellow inventor Alexander Graham Bell to experiment with designs for tetrahedral kites.