The motor is switched off at a height of between 1200 and 1400 feet, and the craft glides nearly 9000 feet before landing.
This gliding without motive power is a safeguard to the airman when he flies across country. Should he attain a sufficient altitude, he has little to fear, even if his engine does fail. As he glides down, he can steer from side to side, or make a half circle and land upon a spot that lies behind him. An aeroplane with a gliding path of 1 foot in 10, and at a height of a mile when its engine stopped, would glide ten miles before alighting. Taking an extreme case, one might imagine an airman flying over a city. Suddenly, while above a network of streets and houses, his engine stops. But even in such a quandary as this, granted he has the wisdom to be several thousand feet high, he need not fear disaster. Glancing keenly below him, he sights some park or open space like an oasis among the close-packed buildings, and glides swiftly and accurately towards it, landing without difficulty or injury to his machine.
The making of a gliding descent, or vol-plané, is an art all airmen learn; and the vital thing to remember in connection with it is, that the machine must always move swiftly forward. Sometimes, checking his glide too soon, a pupil at the schools will make what is called a “pancake” landing: that is to say, misjudging his height above the ground, he stops the glide of his craft, by a movement of the elevating plane, when he is still 15 or 20 feet in the air. The result is that the machine comes to a standstill, then drops flat upon its wheels; and in doing so it may break its chassis supports, and give the pupil a shaking. The art, in a gliding descent, is to lessen the steepness of the dive, by throwing up the elevating plane only a second or so before the landing-wheels make their contact with the ground. Then, its downward speed checked—in the same way that a bird checks itself, just before its feet touch earth—the wheels of the craft will meet the surface smoothly, and there will be no shock or rebound.
A. Upper main plane; B.B. Lower main plane; C.C. Hinged flaps which act as air brakes.
SEEN FROM ABOVE.
AS VIEWED FROM ONE SIDE.