The Airplane - Jay Spenser [76]
The most dramatic use of spoilers is on landing, when they pop up more fully than they can in flight to help slow the airplane. This application of ground spoilers is one of three separate and independent braking systems that jetliners have for decelerating, the others being wheel brakes and thrust reversers. Ground spoilers contribute to stopping in two ways: they provide direct aerodynamic braking, and they kill off the remaining wing lift to drop the airplane’s weight onto its wheels so that its wheel braking is more effective.
For safety, ground spoilers are inhibited in flight. Until signals reach the jet’s computers telling it the airplane has landed, the ground spoilers are not allowed to deploy.
9 FLIGHT DECK
COCKPITS FOR AERIAL SHIPS
Deep into the darkness peering; long I stood there wondering, fearing…
—“THE RAVEN” BY EDGAR ALLAN POE (1809–1849)
As human beings built their flying machines in the opening years of the last century, they gave them open cockpits reminiscent of the wells from which a small sailboat is controlled (indeed, this is where aviation drew the term from). Instead of sheets, a tiller, and a compass, however, these aerial vehicles surrounded their operators with flight controls and instruments.
Early on, people had different ideas of how human beings should physically occupy their airplanes. The Wrights flew lying down, oriented like birds in flight to reduce air resistance. This changed in 1908 with their welcome adoption of upright seating.
When Brazilian aviation pioneer Alberto Santos-Dumont performed Europe’s first officially witnessed hop by a powered aircraft in October 1907, he flew his Santos-Dumont 14-bis standing up. Grafted into the middle of the odd machine’s fuselage was what looked like a wicker balloon basket. It was obvious Santos-Dumont had come to heavier-than-air flight from balloons and dirigibles.
Common sense generally prevailed, however, and most first-generation aviators, successful or not, rightly assumed a person should sit down to fly. But even in the seminal year 1909, when successful flying really took off in the wake of Wilbur’s demonstrations at Le Mans the previous year, this was where agreement ended.
For example, Louis Blériot sat in his Blériot XI like an automobile driver, whereas Hubert Latham sat atop his Antoinette as if crewing a rowboat. And when Santos-Dumont finally came up with a working airplane, he huddled beneath the wing and engine of his Demoiselle. So low was he seated that his gloved hands served as wheel brakes.
Similar confusion attended the flight controls. The Wrights at different times used the motion of pulling back or pushing forward on a lever to lower the nose of their gliders (the latter, being intuitive, won out). As late as 1908, the Wright Model A—their first airplane produced in number—had two different control systems, one reflecting Orville’s preference for rudder actuation and the other Wilbur’s.
Some early airplanes sported control wheels while others had sticks. The Antoinette had fore-and-aft control wheels mounted perpendicular to the direction of flight at the sides of its cockpit. A pilot would control the ailerons by rolling the left-hand wheel forward or backward and the elevator by doing the same with the wheel at right. As for the rudder, a pivoting foot bar controlled that.
The Blériot XI had a wheel on top of a control stick, but this wheel didn’t turn. Instead it simply served as a round grip. The elevator was actuated by moving this wheeled stick forward or aft, while wing warping was controlled by side-to-side movements. The stick could be moved to any quadrant in a circle for combined inputs.
This excellent idea was actually developed independently by Robert Esnault-Pelterie