Really. Believe it or not, a successful aircraft flew using a steam engine for power. Built by Travel Air Manufacturing Co. and modified by Besler Steam Laundry to promote their business, the aircraft first flew on April 12th, 1933 over Oakland, California.
The original Travel Air 2000 was known as the 'Wichita Fokker' because of it's role in numerous Hollywood movies about WWI. It was designed by Lloyd Stearman, and built by his partners Walter Beech and Clyde Cessna. In fact, over half the aircraft built between 1924 and 1930 were produced by their company.
Nathan C. Price, a former Doble Steam Motors engineer contributed to the modified design, and following its unexpectedly favorable reception Price went to work for Boeing, but the company dropped the idea of a steam airplane in 1936. Price later worked for Lockheed where his experience developing compact burners for steam boilers helped him design Lockheed's first jet engine.
Perhaps the strangest feature of the steam powered biplane was how quietly it flew. People on the ground reported they could hear the pilot when he yelled to them from overhead. But it suffered from one major flaw: it used water faster than it used fuel oil and couldn't carry enough water to keep the boiler full for extended flights.