Whitehead wrote a letter to the Editor of the American Inventor, which was published April 1, 1902 which compared planes No. 21 and 22.
"(Number 22) is run by a 40-horsepower kerosene motor of my own design, especially constructed for strength, power and lightness, weighing but 120 pounds complete... Ignition is accomplished by its own heat and compression; it runs about 800 revolutions per minute, has five cylinders and no fly-wheel is used. It requires a space 16 inches wide, 4 feet long and 16 inches high...
"Machine No. 22 is made mostly of steel and aluminum. There is a body 16 feet long, 3 1/2 feet wide and 3 1/2 feet deep, shaped like a fish, and resting on four automobile wheels, 13 inches in diameter.
"While standing on the ground, the two front wheels are connected to the kerosene motor and the rear wheels are used for steering... On either side are large wings or aeroplanes shaped like the wings of a flying fish or bat. The ribs are of steel tubing in No. 22 instead of bamboo as in No. 21 machine and are covered with 450 square feet of the best silk obtainable. In front of the wings and across the body is a steel framework to which is connected the propellers for driving the machine through the air. The propellers are 6 feet in diameter and have a projecting blade-surface of 4 square feet each. They are made of wood and are covered with very thin aluminum sheeting... There is a mast and bowsprit braced something like a ship’s rigging to hold all parts in their proper relations to each other. In the stern of the machine there is a 12-foot tail... which, like the wings, can be folded up in half a minute and laid against the sides of the body...
"In order to start flying, the motor is set in motion and then connected to the front wheels which drive the machine forward. ...When ready to go up, a spring is released which stretches the wings and the propellers are started by means of a lever which stops the ground wheels and turns the power into the propellers. It takes about 20 yards run with the extra weight of a man (about 180 pounds) before the machine leaves the ground."
John Whitehead - the inventor's brother who only saw the planes in a resting state, never in flight described the plane as follows:
"As I remember after 33 years, the shape and size of the machine and motor and material thereof, was as follows: The main body was the shape of a flatbottom rowboat about 18 feet long, 3 1/2 feet wide at the middle, walls about 3 feet high, stern and bow pointed, bottom built of light wood; sides- skeleton frame of wood covered with canvas, wings extending about 20 feet from body on each side, at body side about 10 feet wide, narrowing towards tips of wings. Wings were foldable material of canvas, had at least 6 pairs of bamboo ribs, when spread were held firm with rope on extended bowsprit, from each rib to bottom of body, also from each rib to the sort of mast in center of body. Rudder was a combination of horizontal and vertical fin-like affair, the principle the same as in the up-to-date airplanes. For steering there was a rope from one of the foremost wing tip ribs to the opposite, running over a pulley. In front of the operator was a lever connected to pulley: the same pulley also controlled the tail rudder at the same time. For ground transportation, to get a running start, the machine was resting on three small bicycle wheels, two in fron and one in back.
"The motor of said machine was a 4-cylinder 2-cycle motor of an opposed type... The motor was never tested as to horsepower developed. In my estimation it had from 20-25 horsepower... I know a man could lift one end (of the airplane) off the ground, which lets me guess its weight about 300-400 pounds complete"