Circa 1901, the Number 21 was a single place open cockpit mid-wing monoplane, reportedly had an acetylene gas-powered motor. Silk-covered, twin-tractor powered glider with a birdlike appearance (one of some two dozen Whitehead designs) was claimed by Whitehead, and his many supporters, to have attained powered flight two years before the Wright brothers, on 21 November 1901, but there apparently is no grounded substantiation.

A replica of this craft was built by Otto Timm, for the 1938 film, “Men With Wings,” and another by Andy Kosch in 1986.

A single place multi-rotor type consisting of an open, tubular framework, carrying two rows of 6′ lifting screws on either side of the central frame.

Probably the vehicle was powered with Whitehead’s own engine, fuelled by acetylene.

Whitehead is claimed to have achieved powered flight with this monoplane at Fairfield, Connecticut on August 14, 1901 – more than two years before the Wright brothers’ first flight at Kitty Hawk. In 1968 the state of Connecticut officially recognized Whitehead as the “Father of Connecticut Aviation”.

In the Fairfield field, Gustave Whitehead, taking control of an aircraft of his own design, a 21-horsepower monoplane-type model with 12 horsepower, managed to fly over no less than 850 meters at an altitude of about 15 meters, in the presence of a few witnesses, including a journalist.