этапы отбора и ответы. Этапы отбора и ответы. REV2. Этапы отбора в Аэрофлот
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The parts of an airplane and their functions.The fuselage or body of the airplane, holds all the pieces together. The pilots sit in the cockpit at the front of the fuselage. Passengers and cargo are carried in the rear of the fuselage. Some aircraft carry fuel in the fuselage; others carry the fuel in the wings. To control and maneuver the aircraft, smaller wings are located at the tail of the plane. The tail usually has a fixed horizontal piece, called the horizontal stabilizer, and a fixed vertical piece, called the vertical stabilizer. The stabilizers' job is to provide stability for the aircraft, to keep it flying straight. The vertical stabilizer keeps the nose of the plane from swinging from side to side, which is called yaw. The horizontal stabilizer prevents an up-and-down motion of the nose, which is called pitch. (On the Wright brother's first aircraft, the horizontal stabilizer was placed in front of the wings. Such a configuration is called a canard after the French word for "duck"). At the rear of the wings and stabilizers are small moving sections that are attached to the fixed sections by hinges. Changing the rear portion of a wing will change the amount of force that the wing produces. The ability to change forces gives us a means of controlling and maneuvering the airplane. The hinged part of the vertical stabilizer is called the rudder; it is used to deflect the tail to the left and right as viewed from the front of the fuselage. The hinged part of the horizontal stabilizer is called the elevator; it is used to deflect the tail up and down. The outboard hinged part of the wing is called the aileron; it is used to roll the wings from side to side. Most airliners can also be rolled from side to side by using the spoilers. Spoilers are small plates that are used to disrupt the flow over the wing and to change the amount of force by decreasing the lift when the spoiler is deployed. The spoilers are also used during landing to slow the plane down and to counteract the flaps when the aircraft is on the ground. The wings have additional hinged, rear sections near the body that are called flaps. Flaps are deployed downward on takeoff and landing to increase the amount of force produced by the wing. On some aircraft, the front part of the wing will also deflect. Slats are used at takeoff and landing to produce additional force. Yaw, Roll, PitchThe three motions of the conventional airplane (roll, pitch, and yaw) are controlled by three control surfaces. Roll is controlled by the ailerons; pitch is controlled by the elevators; yaw is controlled by the rudder. Yaw is a motion about the normal axis (directional control). Pitch is a motion about the lateral axis (longitudinal control). Roll is a motion about the longitudinal axis (lateral control). QNH, QFE, QNE, standard pressure (и относительного чего они измеряются)QNH is a local altimeter setting that makes the altimeter indicate the aircraft’s altitude above mean sea level (AMSL) and therefore airfield elevation. There are two types of QNH: 1. Airfield QNH 2. Regional QNH, which is the lowest forecast QNH in an altimeter setting region. QNH is QFE reduced to sea level using international standard atmosphere (ISA) values for the calculation. QFE. This zeros the altimeter on the airfield elevation datum. (Pressure at the airfield). There are two types of QFE: 1. Airfield QFE is measured at the highest point on the airfield. 2. Touchdown QFE is measured at the touchdown point of the runway in use for precision approaches. QNE (standard setting). 29.92 in or 1013 hPa millibars standard setting will give altimeter readings as a pressure altitude or flight level and is used for traffic controlled airspace above the transition layer. QNE is defined as the pressure altitude indicated on landing at an aerodrome, when the altimeter sub scale is set to 1013.2 millibars (hPa). It is used at very high aerodromes where QFE pressure is so low that it cannot be set on the altimeter subscale. Height, Altitude, Flight level, Pressure, pressure altitude, DA(H), MDA(H)Height is the measure of vertical distance between the object and datum. Usually, height is the measured distance above the ground. Altitude is the measured distance above mean sea level (MSL) or above the local pressure setting (i.e., QNH). Flight level is the measured pressure level above the 1013-millibar datum. Flight level corresponds to the Indicated Altitude in feet divided by 100, provided the standard setting is selected. Pressure altitude or pressure height is the international standard atmosphere (ISA) height above the 1013 millibar pressure datum, at which the pressure value experienced represents that of the level under consideration. DA(H) is a specified lowest height or altitude in the approach descent at which, if the required visual reference to continue the approach (such as the runway markings or runway environment) is not visible to the pilot, the pilot must initiate a missed approach. MDA(H) is the lowest height or altitude to which descent is authorized on final approach, or during circle-to-land maneuvering in execution of a non-precision approach. З-н Бернулли, 3 закона Ньютона, эффект МагнусаStatic (atmospheric) pressure is the result of the weight of the atmosphere pressing down on the air beneath. Static pressure will exert the same force per square metre on all surfaces of an airplane. The lower the altitude the greater the force per square metre. Dynamic pressure is the pressure of the air molecules impacting onto a surface caused by either the movement of a body (e.g., an aircraft) through the air or the air flowing over a stationary object. Bernoulli’s Principle states that as the velocity of a moving fluid (liquid or gas) increases, the pressure within the fluid decreases. “In the steady flow of an ideal fluid the sum of the pressure and kinetic energy per unit volume remains constant”. Bernoulli’s theorem when applied to the airflow past an airfoil shows that the total pressure is equal to the sum of the dynamic pressure (the pressure caused by the movement of the air) and the static pressure (the pressure of the air not associated with its movement). Therefore, if static pressure decreases then dynamic pressure increases and vice versa. The highest speed occurs where the pressure is lowest and the lowest speed is where the pressure is highest. This statement can be expressed as: Pressure + Kinetic energy = Constant or: p + 1/2 ρ V2 = Constant. When an airplane flies, some of the air flows over the top of the curved part of the wings, and some go underneath the flat part of the wings. Air speed up over the curved part because of conversation of mass (The Equation of Continuity). Mass cannot be created or destroyed. No matter what physical changes may take place. The flow rate is equal to the mass flowing past divided by the time interval. This means that if the area in which the air is moving narrows or widens, then the air has to speed up or slow down to maintain a constant amount of air moving through the area. The air that flows over top of the wing is fast moving air, which is low pressure, and the air that flows underneath the wing is high pressure. Why does the air pressure go down? For a stream of air to speed up, some of energy from the random motion of the air molecules must be converted into the energy of forward stream flow. The random motion of air molecules is what causes air pressure, so transferring energy from the random motion to the stream flow results in lower air pressure. Since the slow moving air that is high pressure is flowing under the wing, it pushes it up, and there is less pressure from the top, not pushing it down, thus causing lift. Newton’s First Law: “Every object persists in its state of rest or uniform motion in a straight line unless it is compelled to change that state by forces impressed on it.” This means that nothing starts or stops moving until some outside force causes it to do so. An aircraft at rest on the ramp remains at rest unless a force strong enough to overcome its inertia is applied. Once it is moving, its inertia keeps it moving, subject to the various other forces acting on it. These forces may add to its motion, slow it down, or change its direction. Newton’s Second Law: “Force is equal to the change in momentum per change in time. For a constant mass, force equals mass times acceleration.” When a body is acted upon by a constant force, its resulting acceleration is inversely proportional to the mass of the body and is directly proportional to the applied force. This takes into account the factors involved in overcoming Newton’s First Law. It covers both changes in direction and speed, including starting up from rest (positive acceleration) and coming to a stop (negative acceleration or deceleration). Newton’s third law of motion states that for every action there is an equal and opposite reaction. The Newtonian idea is this: air flowing over the wing is ultimately deflected downward by the angle of the wing, and Newton said there has to be an equal and opposite reaction, so the wing is forced upward. In an airplane, the propeller moves and pushes back the air; consequently, the air pushes the propeller (and thus the airplane) in the opposite direction—forward. In a jet airplane, the engine pushes a blast of hot gases backward; the force of equal and opposite reaction pushes against the engine and forces the airplane forward. Magnus effect. Lifting force produced when a rotating cylinder produces a pressure differential. This is the same effect that makes a baseball curve or a golf ball slice. |