William Piper may refer to: William Piper (1774–1852), American politician William Piper (abolitionist) (1786–1870), African-American former slave, conductor on the Underground Railroad and husband of Amelia Piper William Adam Piper (1826–1899), American politician William G. Piper (1906–1976), American politician William T. Piper (1881–1970), American airplane manufacturer, founder of Piper Aircraft William T. Piper Jr. (1911–2007), American businessman, president of Piper Aircraft