Transcript Document
PREJIN VIJESH RAHMAN SAJEER Heavier than air aerodynes, including autogyros, helicopters and variants, and conventional fixed-wing aircraft: aeroplanes in Commonwealth English (excluding Canada), airplanes in North American English. Fixed-wing aircraft generally use an internalcombustion engine in the form of a piston engine (with a propeller) or a turbine engine (jet or turboprop), to provide thrust that moves the craft forward through the air. The movement of air over the airfoil produces lift that causes the aircraft to fly. Exceptions are gliders which have no engines and gain their thrust, initially, from winches or tugs and then from gravity and thermal currents. For a glider to maintain its forward speed it must descend in relation to the air (but not necessarily in relation to the ground). Helicopters and autogyros use a spinning rotor (a rotary wing) to provide both lift and thrust. The abbreviation VTOL is applied to aircraft other than helicopters that can take off or land vertically. STOL stands for Short Take Off and Landing. INFORMATION INFORMATION INFORMATION INFORMATION Forces on an Airplane in Flight The four aerodynamic forces that act upon an airplane in flight are lift (the upward acting force), weight (or gravity, the downward acting force), thrust (the forward acting force), and drag (the air resistance or backward acting force). These four forces are continuously battling each other while an airplane is in flight. LIFT THRUS T DRA G WEIGHT Ailerons The ailerons on an airplane's wings control roll around the longitudinal axis. They work together, simultaneously, tied to the control wheel, or stick, in the cockpit. When the control wheel is turned left, the aileron on the left wing goes up and the one on the right wing goes down. The opposite occurs when the wheel is turned right. But how does this make the airplane roll? The ailerons alter the lifting ability of the wings slightly. When an aileron is lowered, the lift on the outer portion of that wing increases, causing that wing to rise a little. When an aileron is raised, the lift on the outer portion of that wing is decreased slightly, causing that wing to drop a little. Since the ailerons on an airplane work together, their action causes the airplane to roll. Elevators The elevators on the horizontal portion of the tail of an airplane control the pitch of the plane, or its motion around the lateral axis. They are also tied to the control wheel in the cockpit. When the wheel is pulled back, the elevators move upward, causing the tail of the plane to move downward and the nose to pitch upward. When the wheel is pushed forward, the elevators move downward, causing the tail of the plane to rise and the nose to pitch downward. The elevators work like the ailerons on the wings, in that they cause changes in the lift generated by the tail of the plane. Also, the elevators work together, simultaneously, like the ailerons, but they do not work in opposition to one another. Both go up when the control wheel is pulled back and both go down when the control wheel is pushed forward. The rudder on the rear edge of the vertical fin on the airplane's tail controls yaw around the vertical axis. It is connected to the pedals at the pilot's feet. Pushing the right pedal causes the rudder to deflect to the right. This makes the tail of the airplane move toward the left, causing the nose to move to the right. Pushing the left pedal makes the rudder deflect to the left, the tail moves to the right, and the nose points to the left.