Antoinette monoplane

postcard of Antoinette monoplane

Resembling a giant dragonfly, with its long thin body and delicate wings, the Antoinette IV, introduced in October 1908, was an aerodynamically advanced monoplane. It featured a slim fuselage, trapezoidal wings with marked dihedral, and cruciform tail. It was the first practical monoplane with ailerons, although they performed poorly and were replaced with wing warping in later models.

[ad#ad-1]With its monoplane design, pilot & engine location, wheeled landing gear, and tail assembly, the Antoinette, in comparison to the boxy, pusher-prop, canard-using, Wright-style biplanes of 1908, was remarkably advanced. Powered by a 53 h.p. engine, with a wingspread of 46 feet, weighing about 1080 pounds, it could make 52 m.p.h. Not bad for 1909.

According to a contemporary description of the Antoinette, “Above its skifflike aluminum body are spread two oblong rings. The single propeller is situated in front of the main body, while directly below it is the motor, with a self-condensatory boiler. At the rear of the body is the pilot’s seat, and behind him extend two vertical rudders for lateral movements and a horizontal tail for governing the altitude. The underframe of the skiff-like body rests on two wheels, and in front of them is a runner intended to accelerate the leaving of the ground, and to receive the first shock of landing.” (I have not found other references to this report of aluminum in its construction.)

That June, Hubert Latham set an endurance record in his Antoinette, staying aloft for one hour, 7 minutes, 47 seconds. Latham had hoped to make the first air crossing of the English Channel in his Antoinette, but Bleriot beat him to it.

The aviator Harry Harkness flew an Antoinette in an exhibition on Hempstead Plains, Long Island, August 24, 1910, and subsequently wrecked the machine in a hard landing on Sept. 15.

Hubert Latham entered his 50-hp Antoinette in the 1910 World Air Races held at Belmont Park, New York, competing for the Gordon Bennett Trophy.

The Antoinette monoplane evolved from the early experiments of MM. Gastambide and Mangin, and designed by the famous M. Levavasseur, the engine as well as the aeroplane. At the Rheims air race in August, 1909, it was in full working order, and full of interesting features. It was almost entirely constructed of steel tubes covered with aluminum plates, which led some to call it an armored aeroplane, which it was not. The tail, which was one piece with the rudder, was carried on a huge universal joint at the tip of the body, so that it swivelled up or down or sideways in response to the controls. The wings had one huge steel tubular spar, and as a result only one row of interplane struts. The under-carriage had a shock-absorber of a pneumatic- spring construction, which was highly satisfactory, and was the prototype of the elastic-rubber devices. The machine was heavy, but it was fast and a great weight-carrier. Because of minor defects in detail the machine never was generally used, but it was the first step toward the bigger tractor biplanes of World War One.

Description of the Antoinette, from “Monoplanes and Biplanes, …” by Grover Loening, 1911

This machine was controlled transversely by means of wing tips, while at present the warpable surface control is used. The Antoinette is very large and remarkably well built from an engineering standpoint, and has been operated very successfully by M. Latham in exceptionally high winds. Messrs. Kuller, Thomas, and Labouchere, have also flown monoplanes of this type, and several have been purchased by the French army.

The Frame.—A long narrow frame of cedar, aluminum and ash carries at its front portion the wings, at the extreme front end the propeller, and at the rear the rudders. At the nose the frame resembles the hull of a motor boat, while at the rear it is built in the form of a triangular latticed girder.

The Wings.—The wings consist of a single surface divided into two halves of trapezoidal shape set at a slight dihedral angle and constructed of rigid trussing nearly 1 foot thick at the center, covered over and under with a smooth, finely pumiced silk. The wings are also braced from a central mast. The wingspread is 46 feet, the average width 8.2 feet, and the surface area 370 square feet.

The Direction Rudder.—The direction rudder consists of two vertical triangular surfaces at the rear, of 10 square feet area. They are moved jointly by means of wire cables running from a lever worked by the aviator’s feet. When this pedal, which moves in a horizontal plane, is turned to the left the aeroplane will turn to the right.

[ad#ad-1]The Elevation Rudder.—The elevation rudder consists of a single triangular horizontal surface placed at the extreme rear, and 20 square feet in area. It is governed by cables leading from a wheel placed at the aviator’s right hand. To ascend, the wheel is turned up. This causes the inclination of the elevation rudder with regard to the line of flight, to be decreased and the machine, therefore, rises.

Roll Control.—The transverse equilibrium is corrected by warping of the outer ends of the main wings very much as in the Wright machine. But the front ends are movable and the rear ends rigid throughout in the Antoinette, while the opposite is the case in the Wright biplane. The wheel at the aviator’s left hand, through cables and a sprocket gear, placed at the lower end of the central mast, controls the warping. For correcting a dip downward on the right the right end of the wing is turned up, and at the same time the left end is turned down, thus restoring balance.

Keels.—At the rear, leading up to the rudders, are tapered keels, both horizontal and vertical, that add greatly to the bird-like appearance of the aeroplane.

Propulsion.—A 53 horse-power, 8-cylinder Antoinette motor, placed in the nose, drives a two-bladed Normale, wooden, propeller of 7.25 feet diameter and 4.3 feet pitch at 1,100 revolutions per minute.

The seat for the aviator is placed in the frame back of the main plane. A seat for a passenger is provided in front of and a little below the aviator’s seat.

The Mounting is essentially on a large pair of wheels fitted to a pneumatic spring, and placed at the central mast. In addition a single skid to protect the propeller when landing is placed in front, and another is attached in the rear.

Weight, Speed, Loading and Aspect Ratio.— The total weight is from 1,040 to 1,120 pounds; the speed is 52 miles per hour; 22.4 pounds are lifted per horse-power, and 3.03 pounds per square foot of supporting surface. The aspect ratio is 5.6 to 1.

Recent Alterations.—The Antoinette has been slightly altered. The spread is now 49.3 feet, the area 405 square feet, and the total weight from 1,200 to 1,350 pounds. Twenty-seven pounds are lifted per horse-power and 3.33 pounds per square foot of surface. The aspect ratio is 6 to 1. A new 100 horse-power type is also being used for racing.