Aerodynamics 1

=FUNDAMENTALS OF AERODYNAMICS=

BASIC PROPERTIES OF PHYSICS
ELO 1.1 Define scalar quantity, vector, force, mass, volume, density, weight, moment, work, power, energy, potential energy, and kinetic energy.

SCALAR QUANTITY VECTOR FORCE MASS VOLUME DENSITY WEIGHT MOMENT WORK POWER ENERGY POTENTIAL ENERGY KINETIC ENERGY ELO 1.2 State Newton’s three Laws of Motion. NEWTON’S FIRST LAW – THE LAW OF EQUILIBRIUM L = 0 NEWTON’S SECOND LAW – THE LAW OF ACCELERATION a = (VOUT – VIN)/time NEWTON’S THIRD LAW – THE LAW OF INTERACTION ELO 1.3 Identify examples of Newton’s three Laws of Motion. NEWTON’S FIRST LAW – THE LAW OF EQUILIBRIUM NEWTON’S SECOND LAW – THE LAW OF ACCELERATION NEWTON’S THIRD LAW – THE LAW OF INTERACTION ELO 1.4 Define, compare, and contrast equilibrium and trimmed flight. EQUILIBRIUM TRIMMED FLIGHT ELO 1.5 Define static pressure, air density, temperature, lapse rate, humidity, viscosity, and local speed of sound. STATIC PRESSURE AIR DENSITY TEMPERATURE LAPSE RATE HUMIDITY VISCOSITY LOCAL SPEED OF SOUND ELO 1.6 State the relationship between humidity and air density. ELO 1.7 State the relationship between temperature and viscosity. ELO 1.8 State the relationship between temperature and local speed of sound. ELO 1.9 State the pressure, temperature, lapse rate, and air density at sea level in the standard atmosphere using both Metric and English units of measurement.
 * Scalar quantity only represents magnitude, e.g., time, temperature, or volume
 * A vector is a quantity that represents magnitude and direction
 * Commonly used to represent displacement, velocity, acceleration, or force
 * Force is a push or pull exerted on a body (1,000 lbs. of thrust pushes a jet through the sky)
 * Mass is the quantity of molecular material that comprises an object
 * Volume is the amount of space occupied by an object
 * Density is mass per unit volume
 * Weight is the force with which mass is attracted toward the center of the earth by gravity
 * A moment is created when a force is applied at some distance from an axis or fulcrum, and tends to produce rotation about that point
 * A moment is a vector quantity equal to a force time the distance from the point of rotation that is perpendicular to the force
 * Work is done when a force acts on a body and moves it
 * Work is a scalar quantity equal to the force times the distance of displacement
 * Power is the rate of doing work or work done per unit time
 * Energy is a scalar measure of a body’s ability to do work
 * Potential energy is the ability of a body to do work because of its position or state of being
 * Potential energy is a function of mass, gravity, and height
 * Kinetic energy is the ability of a body to do work because of its motion
 * Kinetic energy is a function of mass and velocity
 * A body at rest tends to remain at rest and a body in motion tends to remain in motion in a straight line at a constant velocity unless acted upon by some unbalanced force
 * Equations are: T + W + D = 0
 * An unbalanced force acting on a body produces an acceleration in the direction of the force that is directly proportional to the force and inversely proportional to the mass of the body
 * Equations are: a = F/m
 * For every action, there is an equal and opposite reaction
 * An airplane in straight and level flight at a constant velocity is acted upon by four forces: thrust, drag, lift and weight
 * When thrust is equal to drag, and lift is equal to weight, the airplane is in equilibrium
 * When an airplane’s thrust is greater than its drag (in level flight), the excess thrust will accelerate the airplane until drag increases equal to thrust
 * The thrust from a jet engine consists of hot gases exhausted rearward producing a thrust acting forward
 * Equilibrium is the absence of acceleration, either linear or angular
 * Equilibrium exists when the sum of all the forces and the sum of all the moments around the center of gravity are equal to zero
 * If you are in equilibrium flight, then you are in trimmed flight
 * Trimmed flight exists when the sum of the moments around the center of gravity is zero
 * In trimmed flight, the sum of the forces may not be equal to zero since you can trim an airplane into a turn
 * If you are in trimmed flight, you may not be in equilibrium flight
 * Static pressure is the pressure each air particle exerts on one another
 * Air density is the total mass of air particles per unit of volume
 * Air density decreases with an increase in altitude
 * Temperature is a measure of the average kinetic energy of the air particles
 * Lapse rate is represented by air temperature decreasing linearly with an increase in altitude at a rate of 2 degrees Celsius per 1000 feet until 36,000 feet
 * From 36,000 – 80,000 feet the air remains constant at –56.5 degrees Celsius
 * Humidity is the amount of water vapor in the air
 * As humidity increases, air density decreases
 * Viscosity is a measure of the air’s resistance to flow and shearing
 * Air viscosity increases with an increase in temperature
 * The local speed of sound is the speed at which sound waves travel through a particular air mass
 * As the temperature of air increases, the speed of sound increases
 * As humidity increases, air density decreases
 * Air viscosity increases with an increase in temperature
 * As the temperature of air increases, the speed of sound increases

ELO 1.10 State the relationships between altitude and temperature, pressure, air density, and local speed of sound within the atmosphere. ELO 1.11 State the relationships between pressure, temperature, and air density using the General Gas Law.
 * With increasing altitude:
 * Temperature decreases
 * Pressure decreases
 * Air density decreases
 * Local speed of sound decreases
 * Equation is P = (rho)RT; R is the universal gas constant
 * As density remains constant, increasing temperature increases pressure
 * If pressure remains constant, there is an inverse relationship between density and temperature
 * An increase in temperature must result in a decrease in density, and vice versa

AIRCRAFT TERMINOLOGY
ELO 1.12 Define, compare, and contrast an aircraft and an airplane. AIRCRAFT AIRPLANE ELO 1.13 List and describe the three major control surfaces of an airplane. ELO 1.14 List and define the five major components of an airplane. FUSELAGE WING EMPENNAGE LANDING GEAR ENGINE ELO 1.15 List and define the components of the airplane reference system. ELO 1.16 Describe the orientation between the components of the airplane reference system. ELO 1.17 List and define the motions that occur around the airplane center of gravity. ELO 1.18 Define wingspan, chordline, chord, tip chord, root chord, average chord, wing area, taper, taper ratio, sweep angle, aspect ratio, wing loading, angle of incidence, and dihedral angle. WINGSPAN (b) CHORDLINE CHORD ROOT CHORD (cR) TIP CHORD (cT) AVERAGE CHORD (c) WING AREA (S) TAPER TAPER RATIO (l ) SWEEP ANGLE (L ) ASPECT RATIO (AR) WING LOADING (WL) ANGLE OF INCIDENCE DIHEDRAL ANGLE ELO 1.19 Describe and state the advantages of the semi-monocoque fuselage construction. ELO 1.20 Describe full cantilever wing construction.
 * An aircraft is any device used or intended to be used for flight in the air
 * It is normally supported either by the buoyancy of the structure (balloon, dirigible) or by the dynamic reaction of the air against its surfaces (airplane, glider, helicopter)
 * An airplane is a heavier-than-air-fixed-wing aircraft that is driven by an engine driven propeller or a gas turbine jet and is supported by the dynamic reaction of airflow over its wings
 * The three major control surfaces of an airplane are ailerons, rudders, and elevators
 * Ailerons are control surfaces attached to the wing to control roll
 * The rudder is the upright control surface attached to the vertical stabilizer to control yaw
 * Elevators are the horizontal control surfaces attached to the horizontal stabilizer to control pitch
 * The fuselage is the basic structure of the airplane to which all other components are attached
 * Three type are possible
 * The truss is made of a wood or metal frame with a this skin stretched over it
 * Very heavy, easily repairable
 * The semi-monocoque is a modified version on the monocoque having skin, transverse frame members, and stringers, which all share in stress loads
 * Also easily repaired
 * The full monocoque is extremely light and strong
 * Consists of only a skin that is stressed and impossible to repair if damaged
 * The wing is an airfoil attached to the fuselage and is designed to produce lift
 * A wing may contain fuel cells, engine nacelles, and landing gear
 * A wing contains several parts
 * Ailerons are control surfaces attached to the wing to control roll
 * Flaps are high lift devices attached to the wing to increase lift at low speeds
 * Since all bracing is internal, the wings are called full cantilever
 * The empennage is the assembly of stabilizing and control surfaces on the tail of an airplane
 * Provides the greatest stabilizing influence of all the components of the conventional airplanes
 * Consists of the aft part of the fuselage, the vertical stabilizer, and the horizontal stabilizer
 * The rudder is the upright control surface attached to the vertical stabilizer to control yaw
 * Elevators are the horizontal control surfaces attached to the horizontal stabilizer to control pitch
 * The landing gear permits ground taxi operation and absorbs the shock encountered during takeoff and landing
 * The engine provides the thrust necessary for powered flight
 * Military and commercial airplanes may be fitted with multiple turboprop, turbojet, or turbofan
 * An airplanes reference system consists of three mutually perpendicular lines (axes) intersecting at the center of gravity, the point at which all weight is considered to be concentrated, and about which all forces and moments (yaw, pitch and roll) are measured
 * The center of gravity (C.G.) shifts as fuel burns off, bombs/missiles are expended, or cargo shifts
 * Longitudinal axis stretches from the nose to the tail of the airplane
 * The lateral axis passes from wingtip to wingtip
 * The vertical axis passes vertically through the center of gravity
 * As an airplane moves through the air, the axis system also moves, therefore the movement of the airplane can be described by the movement of its center of gravity
 * Movement of the lateral axis around the longitudinal axis is called roll, or lateral control
 * Movement of the longitudinal axis around the lateral axis is called pitch, or longitudinal control
 * Movement of the longitudinal axis around the vertical axis is called yaw, or directional control
 * As an airplane moves through the air, the axis system also moves, therefore the movement of the airplane can be described by the movement of its center of gravity
 * Movement of the lateral axis around the longitudinal axis is called roll, or lateral control
 * Movement of the longitudinal axis around the lateral axis is called pitch, or longitudinal control
 * Movement of the longitudinal axis around the vertical axis is called yaw, or directional control
 * As an airplane moves through the air, the axis system also moves, therefore the movement of the airplane can be described by the movement of its center of gravity
 * Wingspan is the length of a wing, measured from wingtip to wingtip
 * Chordline is an infinitely long, straight line drawn through the leading and trailing edges of an airfoil
 * Chord is a measure of the width of the wing or other control surface
 * Measured on the chordline from the leading edge to the trailing edge of the airfoil
 * The root chord is the chord at the wing centerline
 * Tip chord is measured at the wingtip
 * Average chord is the average of every chord from the wing root to the wingtip
 * Wing area is the apparent surface area of a wing from wingtip to wingtip
 * S = b x c
 * Taper is the reduction in the chord of an airfoil from root to tip
 * Wings are tapered to reduce weight, improve structural stiffness, and reduce wingtip vortices
 * Taper ratio is the ratio of the tip chord to the root chord
 * l = cT / cR
 * Sweep angle is the angle between a line drawn 25% aft o the leading edge, and a line parallel to the lateral axis
 * Aspect ratio is the ratio of the wingspan to the average chord
 * AR = b / c
 * Wing loading is the ratio of an airplane’s weight to the surface area of its wings
 * WL = aircraft weight / wing area
 * Angle of incidence is the angle between the airplane’s longitudinal axis and the chordline of the wing
 * Dihedral angle is the angle between the spanwise inclination of the wing and the lateral axis
 * The upward slope of the wing when viewed from head on
 * A negative dihedral angle is called an anhedral angle
 * The semi-monocoque is a modified version on the monocoque having skin, transverse frame members, and stringers, which all share in stress loads
 * Very easily repaired
 * Full cantilever wing construction consists of all internal bracing of the wing

BASIC AERODYNAMIC PRINCIPLES
ELO 1.21 Define steady airflow, streamline, and streamtube.

STEADY AIRFLOW STREAMLINE STREAMTUBE ELO 1.22 Describe the relationship between airflow velocity and cross-sectional area within a streamtube using the continuity equation. ELO 1.23 Describe the relationship between total pressure, static pressure, and dynamic pressure within a streamtube using Bernoulli’s equation. ELO 1.24 List the components of the pitot-static system. ELO 1.25 State the type of pressure sensed by each component of the pitot-static system. ELO 1.26 Define indicated airspeed, calibrated airspeed, equivalent airspeed, true airspeed, and ground speed. INDICATED AIRSPEED (IAS) CALIBRATED AIRSPEED (CAS) EQUIVALENT AIRSPEED (EAS) TRUE AIRSPEED (TAS) GROUND SPEED (GS) ELO 1.27 State the corrections between indicated airspeed, calibrated airspeed, equivalent airspeed, true airspeed, and ground airspeed. ELO 1.28 Describe the relationships between indicated airspeed, true airspeed, ground airspeed, and altitude. ELO 1.29 Define the effects of wind on indicated airspeed, true airspeed, and ground speed. ELO 1.30 Given the true airspeed, winds, and time, determine ground speed and distance traveled. ELO 1.31 Define Mach number and critical Mach number. MACH NUMBER CRITICAL MACH NUMBER (MCRIT) ELO 1.32 Describe the effect of altitude on Mach number and critical Mach number.
 * Exists if at every point in the airflow, velocity, density, temperature, and pressure (VDTP) remain constant over time.
 * A streamline is the path that air particles follow in steady airflow
 * A streamtube consists of many different streamlines
 * A closed system so total mass and total energy must remain constant
 * Energy cannot be removed or added, it can merely be changed from one form to another
 * Velocity and area in a streamtube are inversely related
 * A1V1 = A2V2
 * Mass flow is equal to the density times the area time the volume
 * Mass flow = (rho)AV
 * The density times the volume times the area are equal to the same for each cross section of the streamtube
 * (rho)1A1V1 = (rho)2A2V2
 * Total pressure (PT), also called head pressure (HT), is the sum of static and dynamic pressure
 * Static pressure (PS) is a measure of potential energy per unit volume
 * Dynamic pressure (q) is the pressure of a fluid resulting from its motion, and is equal to 1/2(rho)V*2
 * Equation is PT = PS + q
 * Static pressure and dynamic pressure are inversely related
 * The pitot static system consists of the pitot-tube and a static pressure source connected to a "black box"
 * The pitot-tube is the device that collects total pressure (PT)
 * The static pressure port is the device that collects ambient static pressure (PS)
 * Indicated air speed is the instrument indication for the dynamic pressure the airplane is creating during flight
 * Calibrated airspeed is the indicated airspeed corrected for instrument error
 * Equivalent airspeed is the true airspeed at sea level on a standard day that produces the same dynamic pressure as the total flight condition
 * EAS is found by correcting the calibrated airspeed for compressibility error
 * True air speed is the actual velocity at which the airplane moves through an air mass
 * TAS will equal IAS only under standard day, sea level conditions
 * Ground speed is a measure of the airplane’s actual speed over the ground
 * GS = TAS +/- the headwind/tailwind
 * EAS is found by correcting the calibrated airspeed for compressibility error
 * Calibrated airspeed is the indicated airspeed corrected for instrument error
 * TAS will equal IAS only under standard day, seal level conditions
 * GS = TAS +/- the headwind/tailwind
 * A rule of thumb is that TAS will be three knots faster than IAS for every 1,000 feet of altitude increase
 * The density changes with an increase in altitude
 * The equation is given as TAS = ((rho)0/(rho))*(1/2) x IAS
 * Correcting TAS for wind gives us GS
 * Equation is given by GS = TAS +/- headwind
 * Use the equation GS = TAS +/- headwind to determine ground speed
 * To determine distance measure the ground speed times the amount of time at that speed to determine distance
 * Mach number is the ratio of the airplane’s true airspeed to the local speed of sound
 * Equation is M = TAS / LSOS
 * Critical mach number is the free airstream mach number that produces the first evidence of local sonic flow
 * Airplanes exceeding this number will have supersonic flow somewhere on the aircraft
 * As the altitude increases, temperature decreases resulting in a decrease in Local Speed of Sound (LSOS)
 * Therefore there is in an increase in Mach (M) and Critical Mach (Mcrit) (M = TAS / LSOS)

LIFT AND STALLS
ELO 1.33 Define pitch attitude, flight path, relative wind, angle of attack, mean camber line, positive camber airfoil, negative camber airfoil, symmetric airfoil, aerodynamic center, airfoil thickness, spanwise flow, chordwise flow, aerodynamic force, lift and drag. PITCH ATTITUDE (q ) FLIGHT PATH RELATIVE WIND ANGLE OF ATTACK (a ) MEAN CAMBER LINE POSITIVE CAMBER AIRFOIL NEGATIVE CAMBER AIRFOIL SYMMETRIC AIRFOIL AERODYNAMIC CENTER AIRFOIL THICKNESS SPANWISE FLOW CHORDWISE FLOW AERODYNAMIC FORCE (AF) LIFT (L) DRAG (D) ELO 1.34 Describe the effects on dynamic pressure, static pressure, and the aerodynamic force as air flows around a cambered airfoil and a symmetric airfoil. CAMBERED AIRFOIL SYMMETRIC AIRFOIL ELO 1.35 Describe the effects of changes in angle of attack on the pressure distribution and aerodynamic force of cambered and symmetric airfoils. CAMBERED AIRFOIL SYMMETRIC AIRFOIL ELO 1.36 Describe the effects of changes in density, velocity, surface area, camber, and angle of attack on lift. ELO 1.37 List the factors affecting lift that the pilot can directly control. ELO 1.38 Compare and contrast the coefficients of lift generated by cambered and symmetric airfoils. CAMBERED AIRFOILS SYMMETRIC AIRFOILS ELO 1.39 Describe the relationships between weight, lift, velocity, and angle of attack in order to maintain straight and level flight, using the lift equation. ELO 1.40 Define boundary layer. ELO 1.41 List and describe the types of boundary layer airflow. LAMINAR FLOW TURBULENT FLOW ELO 1.42 State the advantages and disadvantages of each type of boundary layer airflow. ELO 1.43 State the cause and effects of boundary layer separation. ELO 1.44 Define stall and state the cause of a stall. ELO 1.45 Define and state the importance of CLMAX and CLMAX AOA. CLMAX CLMAX AOA ELO 1.46 State the procedures for stall recovery. ELO 1.47 List the common methods of stall warning, and identify those on the T-34 or T-37. ELO 1.48 State the stalling AOA on the T-34C. ELO 1.49 Define stall speed. ELO 1.50 Describe the effects of weight, altitude, and thrust on true and indicated stall speed, using the appropriate equation. IASS = ÷ [(2W)/(r 0SCLMAX) - Including thrust, the equation is as follows: VS = ÷ [(2(W-Tsinq )/(r SCLMAX)] IASS =÷ [(2(W-Tsinq ))/(r 0SCLMAX)] ELO 1.51 State the purpose of high lift devices. ELO 1.52 State the effect of boundary layer control devices on the coefficient of lift, stalling AOA, and stall speed. ELO 1.53 Describe the different types of boundary layer control devices. FIXED SLOTS AUTOMATIC SLOTS ELO 1.54 Describe the operation of boundary layer control devices. ELO 1.55 State the effects of flaps on the coefficient of lift, stalling AOA, and stall speed. ELO 1.56 Describe different types of flaps. TRAILING EDGE FLAPS LEADING EDGE FLAPS ELO 1.57 State the methods used by each type of flap to increase the coefficient of lift. ELO 1.58 State the stall pattern exhibited by rectangular, elliptical, moderate taper, high taper and swept wing planforms. RECTANGULAR ELLIPTICAL MODERATE TAPER HIGH TAPER SWEPT WING ELO 1.59 State the advantages and disadvantages of tapering the wings of the T-34 and T-37. ELO 1.60 State the purpose of wing tailoring. ELO 1.61 Describe different methods of wing tailoring. GEOMETRIC TWIST AERODYNAMIC TWIST ELO 1.62 State the types of wing tailoring used on the T-34 and the T-37.
 * Pitch attitude is the angle between an airplane’s longitudinal axis and the horizon
 * Flight path is the path described by an airplane’s center of gravity as it moves through and air mass
 * Relative wind is the airflow the airplane experiences as it moves through the air
 * It is equal in magnitude and opposite in direction to the flight path
 * Angle of attack is the angle between the relative wind and the chordline of an airfoil
 * The mean camber line is a line drawn halfway between the upper and lower surfaces
 * Positive camber airfoil occurs when the mean camber line is above the chordline
 * Negative camber airfoil occurs when the mean camber line is below the chordline
 * Symmetric airfoil occurs when the mean camber line is coincident with the chordline
 * The aerodynamic center, or quarter chord point, is the point along the chordline where all changes in the aerodynamic force takes place
 * Airfoil thickness is the height of the airfoil profile
 * The point of thickness corresponds to the aerodynamic center
 * Spanwise flow is airflow that travels along the span of the wing, parallel to the leading edge
 * Spanwise is from the root to the tip
 * Chordwise flow is air flowing at right angles to the leading edge of an airfoil
 * It is the only flow that accelerates over a wing, it is the only airflow that produces lift
 * Aerodynamic force is a force that is the result of pressure and friction distribution over an airfoil, and can be resolved into two components, lift and drag
 * Lift is the component of the aerodynamic force acting perpendicular to the relative wind
 * Drag is the component of the aerodynamic force acting parallel to and in the same direction as the relative wind
 * Because of the positive camber, the area in the streamtube above the wing is smaller than the area in the streamtube below the wing; therefore the airflow velocity above the wing is greater than the velocity below the wing
 * The static pressure on the upper surface will be less than on the lower surface, creating a pressure differential
 * The lower static pressure on the upper surface will pull the wing upward, creating a lifting force
 * A symmetric airfoil produces identical velocity and static pressure decreases on both the upper and lower surfaces
 * Due to no pressure differential, no net lift is created
 * Increasing angle of attack on any airfoil causes the area of the streamtube above the wing to decrease
 * This produces a greater velocity increase above the wing than below the wing
 * The greater velocity increases the pressure differential on a cambered airfoil
 * The greater pressure differential on the airfoil will increase the magnitude of the aerodynamic force
 * Increasing angle of attack on any airfoil causes the area of the streamtube above the wing to decrease
 * This produces a greater velocity increase above the wing than below the wing
 * The greater velocity creates a pressure differential on a symmetric airfoil
 * The greater pressure differential on the airfoil will increase the magnitude of the aerodynamic force
 * Density
 * An increase in density will produce greater lift
 * Velocity
 * An increase in velocity will produce greater lift
 * Surface Area
 * An increase in wing surface area produces greater lift
 * Camber
 * Positive camber increases pressure differential and results in increased lift
 * Angle of Attack
 * Increased angle of attack increases lift
 * The factors affecting lift that the pilot can control are angle of attack, velocity, and camber.
 * Positive camber
 * At zero angle of attack there is a positive coefficient of lift
 * For a coefficient of lift of zero, the positive camber requires a negative angle of attack
 * Negative camber
 * At zero angle of attack there is a negative coefficient of lift
 * For a coefficient of lift of zero, the negative camber requires a positive angle of attack
 * At zero angle of attack there is a coefficient of lift of zero
 * As angle of attack increases, the only way to maintain level flight is to decrease velocity
 * If velocity is not decreased, lift will be greater than weight, and the airplane will climb
 * Velocity and angle of attack are inversely related in flight
 * The lift equation is given as follows: L = _ r V2 Ø SCL ≠
 * As angle of attack continues to increase, the coefficient of lift increases up to a maximum called CLMAX
 * Any increase beyond CLMAX causes a decrease in coefficient of lift, so we call CLMAX AOA the most effective angle of attack
 * The boundary layer is that layer of airflow over a surface that demonstrates local airflow retardation due to viscosity
 * Usually only 1mm thick at the leading edge of the airfoil
 * In laminar flow, the air molecules move smoothly along in streamlines
 * The laminar layer produces very little friction, but is easily separated from the surface
 * In turbulent flow, the streamlines break up and the flow is disorganized and irregular
 * The turbulent layer produces higher friction drag, but adheres to the upper surface of the airfoil, delaying boundary layer separation
 * The laminar layer produces very little friction, but is easily separated from the surface of the airfoil
 * The turbulent layer produces higher friction drag, but adheres to the surface of the airfoil, delaying boundary layer separation
 * The adverse pressure gradient impedes the flow of the boundary layer
 * If the boundary layer does not have sufficient kinetic energy to overcome the adverse pressure gradient, the lower levels of the boundary layer will stagnate
 * The boundary layer will separate from the surface and cause the airfoil to lose the suction pressure that creates lift
 * A stall is a condition of flight where an increase in AOA has resulted in a decrease in CL
 * The only cause of a stall is excessive AOA
 * CLMAX is the maximum coefficient of lift at the maximum angle of attack
 * Any angle of attack greater produces a lesser CL
 * CLMAX AOA is the stalling angle of attack or critical angle of attack, and the region beyond the CLMAX AOA is known as the stall region
 * The wing will always stall beyond the CLMAX AOA, regardless of the flight conditions or airspeed
 * The only action necessary for stall recovery is to decrease the AOA below the CLMAX AOA
 * Common methods of stall warnings include AOA indicators, rudder pedal shakers, stick shakers, horns, buzzers, warning lights and electronic voices
 * Stall warning in the T-37 is accomplished with aerodynamic stick shakers
 * Stall warning in the T-34 is accomplished with rudder pedal shakers and airframe buffeting occurring at 26.5 units AOA
 * The T-34 stalls between 29.0 and 29.5 units AOA
 * The T-34 stalls between 29.0 and 29.5 units AOA
 * Stall speed (VS) is the minimum true airspeed required to maintain level flight at CLMAX AOA
 * As an airplane’s weight decreases stall speed decreases
 * Increasing altitude will increase stall speed
 * Indicated stall speed will not change as altitude changes
 * The equation is given as follows: VS = ÷ [(2W)/(r SCLMAX)]
 * The purpose of high lift devices is to reduce takeoff and landing speeds by reducing stall speed
 * Both CLMAX and CLMAX AOA increase with the use of boundary layer controls
 * Fixed slots are gaps located at the leading edge of a wing that allow air to flow from below the wing to the upper surface
 * High pressure air from the leading edge stagnation point is directed through the slot, which acts as a nozzle converting the static pressure into dynamic pressure
 * The high kinetic energy air leaving the nozzle increases the energy of the boundary layer and delays separation
 * Small increase in drag is created
 * Automatic slots are created by slats which are moveable leading edge sections
 * As a slat opens it creates a slot, and it can open mechanically, hydraulically, electrically, or by the chordwise circulation of airflow around the wing
 * As a slat opens it creates a slot, and it can open mechanically, hydraulically, electrically, or by the chordwise circulation of airflow around the wing
 * Aerodynamic deployment occurs when the dynamic pressure generated in flight decreases to the point that it is overcome by the chordwise circulation
 * Mechanical occurs when the pilot or onboard computer lowers the flaps
 * When the flaps are extended, it increases the airfoil’s positive camber thus shifting its zero lift point to the left decreasing the stalling CLMAX AOA
 * These make for flatter take off and landing visibility
 * PLAIN FLAP
 * A plain flap is a simple hinged portion of the trailing edge that is forced down into the airstream to increase the camber of the airfoil
 * SPLIT FLAP
 * A split flap is a plate deflected from the lower surface of the airfoil
 * Creates a lot of turbulence because of the turbulent air between the wing and deflected surface
 * SLOTTED FLAP
 * A slotted flap is similar to the plain flap, but moves away from the wing to open a narrow slot between the flap and wing for boundary layer control
 * Causes a slight, but insignificant increase in wing area
 * FOWLER FLAP
 * A fowler flap is used extensively on larger airplanes
 * Moves down increasing the camber
 * Causes an increase in wing area
 * PLAIN FLAP
 * Similar to trailing edge plain flaps
 * SLOTTED FLAP
 * Similar to trailing edge slotted flaps
 * A plain flap is a simple hinged portion of the trailing edge that is forced down into the airstream to increase the camber of the airfoil
 * Causes a slight, but insignificant increase in wing area
 * Moves down increasing the camber
 * Causes an increase in wing area
 * Since the area of highest lift coefficient will stall first, the rectangular wing has a strong root stall tendency
 * Limited to low speed, lightweight airplanes
 * Provides adequate stall warning and aileron effectiveness
 * The elliptical has an even distribution of lift from the root to the tip and produces minimum induced drag
 * An even lift distribution means that all sections stall at the same angle of attack
 * Little advanced warning and aileron effectiveness may be lost near stall
 * Moderate taper wings have a lift distribution and stall pattern similar to the elliptical wing
 * Pilot will lose lateral control of airplane due to the ailerons being located at the tips of the wings
 * A highly tapered wing is desirable from the standpoint of structural weight, stiffness, and wingtip vortices
 * Tapered wings produce most of the lift toward the tip, therefore they have a strong tip stall tendency
 * Swept wings are used on high speed aircraft because they reduce drag and allow the airplane to fly at higher mach numbers
 * Have a strong tip stall tendency and stall easily
 * When the wingtip stalls it rapidly progresses over the entire wing
 * The advantages to using swept wings are reduced weight, improved stiffness, and reduced wingtip vortices
 * Pilot will lose lateral control of airplane due to the ailerons being located at the tips of the wings
 * Wing tailoring is used to create a root to tip progression and give the pilot some stall warning while ensuring that the ailerons remain effective up to a complete stall
 * Geometric twist is a decrease in angle of incidence from wing root to wingtip
 * Results in a decreased angle of attack at the wingtip
 * The root stalls first
 * Aerodynamic twist is a decrease in camber from wing root to wingtip
 * Wing root stalls before the tip due to positive camber airfoils stalling at lower angles of attack
 * The T-34 wing is geometrically twisted 3.1 degrees
 * The T-37 wing is geometrically twisted 2.5 degrees
 * The wings of the T-34 and T-37 are aerodynamically twisted to create a reduced camber at the tip

DRAG
ELO 1.63 Define total drag, parasite drag, and induced drag. TOTAL DRAG PARASITE DRAG INDUCED DRAG ELO 1.64 List the three major types of parasite drag. FORM DRAG FRICTION DRAG INTERFERENCE DRAG ELO 1.65 State the cause of each major type of parasite drag. ELO 1.66 State the aircraft design features that reduce each major type of parasite drag. ELO 1.67 Describe the effects of changes in density, velocity, and equivalent parasite area on parasite drag, using the parasite drag equation. ELO 1.68 Describe the effects of upwash and downwash on the lift generated by an infinite wing. UPWASH DOWNWASH ELO 1.69 Describe the effects of upwash and downwash on the lift generated by a finite wing. ELO 1.70 State the cause of induced drag. ELO 1.71 State the aircraft design features that reduce induced drag. ELO 1.72 Describe the effects of changes in lift, weight, density, and velocity on induced drag, using the induced drag equation. ELO 1.73 Describe the effects of changes in velocity on total drag. ELO 1.74 Define and state the purpose of the lift to drag ratio. ELO 1.75 State the importance of L/DMAX.
 * Total drag is the component of the aerodynamic force that is parallel to the relative wind, and acts in the same direction
 * Parasite drag is defined as all drag that is not associated with the production of lift
 * Induced drag is that portion of total drag associated with the production of lift
 * Form drag, also known as pressure or profile drag, is caused by the airflow separation from a surface and the wake that is created by the separation
 * Form drag would be temporarily significant until the aircraft velocity decreased to match the higher angle of attack
 * To reduce form drag, the fuselage, bombs, and other exposed surfaces are streamlined
 * Friction drag is created in the boundary layer, which is produced due to viscosity
 * Friction drag can be reduced by smoothing the exposed surfaces of the airplane through painting, cleaning, waxing or polishing
 * Interference drag is generated by the mixing of streamlines between one or more components
 * Accounts for 5 to 10 percent of drag on an airplane
 * Reduced by proper fairing and filleting which allows streamlines to meet gradually rather than abruptly
 * Form drag, also known as pressure or profile drag, is caused by the airflow separation from a surface and the wake that is created by the separation
 * Friction drag is created in the boundary layer, which is produced to viscosity
 * Interference drag is generated by the mixing of streamlines between one or more components
 * To reduce form drag, the fuselage, bombs, and other exposed surfaces are streamlined
 * Friction drag can be reduced by smoothing the exposed surfaces of the airplane through painting, cleaning, waxing or polishing
 * Interference can be reduced by proper fairing and filleting which allows streamlines to meet gradually rather than abruptly
 * Parasite drag varies directly with velocity squared, meaning doubling speed causes four times the drag
 * Increasing density increases drag
 * Equivalent parasite area (f) is a mathematically computed value equal to the area of a flat plate perpendicular to the wind that would produce the same amount of drag as form drag, friction drag, and interference drag combined
 * Equation is given as DP = _ r V2f = qf
 * Upwash is air that should have passed under the wing but flowed up and over the wing
 * Upwash increases lift because it increases the average angle of attack on the wing
 * Downwash is air on top of the wing that flows down and under the trailing edge
 * Downwash decreases lift by reducing the average angle of attack on the wing
 * For an infinite wing, the upwash exactly balances the downwash resulting in no net change in lift
 * Downwash and upwash exists any time an airfoil produces lift
 * The wind flows around the wingtips, combines with the chordwise flow that has already produced lift and adds to the downwash
 * Downwash approximately doubles by this process due to the spanwise airflow moving around the formation of wingtip vortices
 * Induced drag is caused by the parallel component of total lift
 * Induced drag varies inversely with velocity and directly with the angle of the attack
 * Winglets, wingtip tanks, and missile rails have all been added to the aircraft design to reduce induced drag
 * Increased weight increases drag
 * Increasing density reduces induced drag
 * Increasing velocity reduces induced drag
 * Increasing wingspan reduces induced drag
 * The equation is given as DI = [(KL2)/(r V2b2)] = [(KW2)/(r V2b2)]
 * Total drag increases with increasing velocity from the point where induced drag and parasite drag intersect
 * The lift to drag ratio is used to determine the efficiency of an airfoil
 * A high lift to drag ration indicates a more efficient airfoil
 * L/Dmax AOA produces the minimum total drag
 * At L/Dmax AOA, parasite drag and induced drag are equal
 * L/Dmax AOA produces the greatest ratio of lift to drag
 * L/Dmax AOA is the most efficient angle of attack

THRUST AND POWER
ELO 1.76 Describe the relationship between thrust and power. ELO 1.77 Define thrust required and power required. ELO 1.78 Describe how thrust required and power required varies with velocity. ELO 1.79 State the location of L/Dmax on the thrust required and power required curve. ELO 1.80 Define thrust available and power available. THRUST AVAILABLE POWER AVAILABLE ELO 1.81 Describe the effects of throttle setting, velocity, and density on thrust available and power available for a turbojet engine. ELO 1.82 Describe the effects of PCL setting, velocity, and density on thrust available and power available for a turboprop engine. ELO 1.83 Define thrust horsepower, shaft horsepower, and propeller efficiency. THRUST HORSEPOWER (THP) SHAFT HORSEPOWER (SHP) PROPELLER EFFICIENCY (p.e.) ELO 1.84 State the relationship between thrust horsepower, shaft horsepower, and propeller efficiency. ELO 1.85 State the flat rated shaft horsepower and the Navy limited shaft horsepower of the T-34C PT6A-25 engine. ELO 1.86 State the instrument indications for the flat rated shaft horsepower and the Navy limited shaft horsepower of the T-34C PT6A-25 engine. ELO 1.87 State the sea level rated thrust of each T-37B J69-T-25A engine. ELO 1.88 State the instrument indications for the sea level rated thrust of the T-37B J69-T-25A. ELO 1.89 Define thrust excess and power excess. THRUST EXCESS (TE) POWER EXCESS (PE) ELO 1.90 State the effects of a thrust excess or a power excess. THRUST EXCESS POWER EXCESS ELO 1.91 State the conditions necessary to achieve the maximum thrust excess and maximum power excess for a turbojet and turboprop airplane. MAXIMUM THRUST EXCESS MAXIMUM POWER EXCESS ELO 1.92 Describe the effects of changes in weight on thrust required, power required, thrust available, and power available. ELO 1.93 Describe the effects of changes in weight on maximum thrust excess and maximum power excess, and on the airspeeds necessary to achieve maximum thrust excess and maximum power excess. ELO 1.94 Describe the effects of changes in altitude on thrust required, power required, thrust available, and power available. ELO 1.95 Describe the effects of changes in altitude on maximum thrust excess and maximum power excess, and on the airspeeds necessary to achieve maximum thrust excess and maximum power excess. ELO 1.96 Describe the effects of changes in configuration on thrust required, power required, thrust available, and power available. ELO 1.97 Describe the effects of changes in configuration on maximum thrust excess and maximum power excess, and on the airspeeds necessary to achieve maximum thrust excess and maximum power excess.
 * Power required is equal to the thrust required times the velocity, divided by 325
 * Equation is given as Pr = (TrxV) / 325
 * Thrust required is the amount of thrust required to overcome drag
 * Power required is the amount of power that is necessary to produce the thrust required
 * As power is increased, thrust is increased to the L/Dmax, which represents the minimum total drag
 * L/Dmax is at the bottom of the thrust required curve
 * L/Dmax is not at the bottom of the PR curve, it is to the right of the bottom of the curve
 * Thrust available is the amount of thrust that the airplane’s engines are actually producing at a given throttle setting, velocity, and density
 * Power available is the amount of power that the airplane’s engine(s) is(are) actually producing, at a given throttle, velocity, and density
 * The most important factor is throttle
 * As velocity increases, power available increases linearly
 * Thrust available decreases with a decrease in density
 * Power available also decreases with a decrease in density
 * Maximum engine output occurs at full throttle (PCL setting, power control level)
 * As velocity increases, thrust avialable decreases.
 * As velocity increases, power available for a prop will initially increase, but then decrease due to a decrease in thrust available
 * Power available is determined by the performance of the engine/propeller combination
 * As density increases the blade angle changes to take a bigger "bite" out of the air
 * Thrust horsepower is propeller output, or the horsepower that is converted to thrust by the propeller
 * Shaft horsepower is engine output
 * Propeller efficiency is the ability of the propeller to turn engine output into thrust
 * Thrust horsepower is equal to the shaft horsepower times the propeller efficiency
 * Equation is given as THP = SHP x p.e.
 * At seal level, the PT6A-25 engine in the T-34C is flat rated at 550 SHP (1315 ft-lbs. of torque), but is Navy limited to 425 SHP (1015 ft-lbs. torque) in order to extend the service life of the engine
 * At seal level, the PT6A-25 engine in the T-34C is flat rated at 550 SHP (1315 ft-lbs. of torque), but is Navy limited to 425 SHP (1015 ft-lbs. torque) in order to extend the service life of the engine
 * At seal level, each J69-T-25A engine in the T-37B is flat rated at 1025 lbs. of thrust at 100% RPM but is limited to 95% RPM for continuous operation
 * At seal level, each J69-T-25A engine in the T-37B is flat rated at 1025 lbs. of thrust at 100% RPM but is limited to 95% RPM for continuous operation
 * Thrust excess occurs if thrust available is greater than thrust required at a particular velocity
 * Power excess is calculated in a similar manner as TE and will also produce an acceleration, a climb, or both
 * A positive thrust excess causes an acceleration, a climb, or both, depending on angle of attack
 * A negative thrust excess is called a thrust deficit and has the opposite effect
 * A power excess causes an acceleration, a climb, or both
 * A power deficit will cause a decent, a deceleration, or both
 * Maximum thrust excess occurs in turbojets at L/Dmax
 * Maximum thrust excess occurs in turboprops at a velocity less than L/Dmax
 * Maximum power excess occurs in turbojets at a velocity greater than L/Dmax
 * Maximum power excess occurs in turboprops at L/Dmax
 * The net result of an increase in weight is that the Tr and Pr curves will shift up and right
 * Weight changes have no effect on thrust available or power available
 * Thrust excess and power excess decrease at every AOA and velocity
 * The net result of an increase in weight is that the L/Dmax will shift up and right
 * With an increase in altitude, the thrust required shifts right only
 * With an increase in altitude, the power required shifts up and to the right
 * Thrust available decreases with altitude
 * Power available decreases with altitude
 * Thrust excess and power excess decrease with an increase in altitude
 * Increased airspeed is necessary to achieve maximum thrust and power excess
 * Thrust and power required both shift up only with deployment of landing gear
 * Thrust and power available are not affected by the deployment of landing gear
 * Thrust and power required both shift up and left with deployment of flaps
 * Thrust and power available are not affected by the deployment of flaps
 * Maximum thrust excess and maximum power excess decrease with the deployment of the landing gear
 * The velocity remains constant to achieve maximum thrust and power for deployment of the landing gear
 * Maximum thrust excess and maximum power excess decrease with deployment of flaps
 * Velocity required to achieve maximum power and thrust excess decreases

AIRCRAFT PERFORMANCE
ELO 1.98 State the relationship between fuel flow, thrust available, thrust required, and velocity for a turbojet airplane in straight and level flight. ELO 1.99 State the relationship between fuel flow, thrust available, thrust required, and velocity for a turboprop airplane in straight and level flight. ELO 1.100 Define maximum endurance and maximum range. MAXIMUM ENDURANCE MAXIMUM RANGE ELO 1.101 State the angle of attack and velocity, compared to L/DMAX, at which turbojet and turboprop airplanes achieve maximum endurance. TURBOJET TURBOPROP ELO 1.102 State the angle of attack and velocity, compared to L/DMAX, at which turbojet and turboprop airplanes achieve maximum range. TURBOJET TURBOPROP ELO 1.103 Describe the effects of changes in weight, altitude, configuration, and wind on maximum endurance and maximum range performance and airspeed. WEIGHT ALTITUDE CONFIGURATION WIND ELO 1.104 Define maximum angle of climb and maximum rate of climb. MAXIMUM ANGLE OF CLIMB MAXIMUM RATE OF CLIMB ELO 1.105 State the angle of attack and velocity, compared to L/DMAX, at which turbojet and turboprop airplanes achieve maximum angle of climb. TURBOJET TURBOPROP ELO 1.106 State the angle of attack and velocity, compared to L/DMAX, at which turbojet and turboprop airplanes achieve maximum rate of climb. TURBOJET TURBOPROP ELO 1.107 Describe the effect of changes in weight, altitude, configuration, and wind on maximum angle of climb and maximum rate of climb performance and airspeed. WEIGHT ALTITUDE CONFIGURATION WIND ELO 1.108 Define absolute ceiling, service ceiling, cruise ceiling, combat ceiling, and maximum operating ceiling. ABSOLUTE CEILING SERVICE CEILING CRUISE CEILING COMBAT CEILING MAXIMUM OPERATING CEILING ELO 1.109 State the maximum operating ceiling of the T-34 and T-37. ELO 1.110 Define maximum glide range and maximum glide endurance. MAXIMUM GLIDE RANGE MAXIMUM GLIDE ENDURANCE ELO 1.111 State the angle of attack and velocity, compared to L/DMAX, at which an airplane achieves maximum glide range. ELO 1.112 State the angle of attack and velocity, compared to L/DMAX, at which an airplane achieves maximum glide endurance. ELO 1.113 Describe the effects of changes in weight, altitude, configuration, wind, and propeller feathering on maximum glide range and maximum glide endurance performance and airspeed. WEIGHT ALTITUDE CONFIGURATION WIND PROPELLER FEATHERING ELO 1.114 Define the regions of normal and reverse command as they relate to maximum endurance angle of attack and velocity. REGION OF NORMAL COMMAND REGION OF REVERSE COMMAND ELO 1.115 Describe the relationship between velocity and throttle setting required to maintain level flight within the region of normal and reverse command.
 * The fuel consumed is proportional to the airplane’s thrust available
 * Minimum fuel flow for a turbojet is found on the thrust required curve
 * In order to maintain equilibrium flight, thrust available must equal thrust required
 * The thrust provided by a propeller is not produced directly by the engine, so there is no direct relationship between fuel flow and thrust
 * Fuel flow varies directly with the power output of the engine
 * Minimum fuel flow will be found on the power required curve
 * Maximum endurance is the maximum amount of time that an airplane can remain airborne on a given amount of fuel
 * Maximum range is the maximum distance traveled over the ground for a given amount of fuel
 * Turbojet airplanes achieve maximum endurance at L/DMAX AOA and velocity
 * Turboprop airplanes achieve maximum endurance at a velocity less than L/DMAX and an angle of attack greater than L/DMAX AOA
 * Turbojet airplanes achieve maximum range at an angle of attack less than L/DMAX AOA and at a velocity greater than L/DMAX
 * Turboprop airplanes achieve maximum range at L/DMAX AOA and velocity
 * Maximum range and endurance are both decreased with an increase in weight
 * Maximum range and endurance are both increased with an increase in altitude
 * Maximum range and endurance are both decreased with the deployment of flaps or landing gear
 * Winds will have no effect on maximum endurance
 * Headwinds will decrease maximum range
 * Tailwinds will increase maximum range
 * Maximum angle of climb desires maximum vertical velocity (altitude increase) for a minimum horizontal velocity (ground speed)
 * Used to take off from a short airfield
 * Maximum rate of climb is a comparison of altitude gained relative to the time needed to reach the altitude
 * Used to gain the greatest vertical distance in the shortest amount of time
 * Maximum angle of climb for a turbojet occurs at L/DMAX AOA and velocity
 * Maximum angle of climb for a turbojet occurs at a velocity less than L/DMAX and an angle of attack greater than L/DMAX AOA
 * Maximum rate of climb for a turbojet occurs at a velocity greater than L/DMAX and an angle of attack less than L/DMAX AOA
 * Maximum rate of climb for a turboprop occurs at L/DMAX AOA and velocity
 * Maximum angle and rate of climb are both decreased with an increase in weight
 * Maximum angle and rate of climb are both decreased with an increase in altitude
 * Maximum angle and rate of climb are both decreased with the deployment of flaps or landing gear
 * Winds will have no effect on rate of climb performance
 * Headwinds will increase the airplane’s maximum angle of climb
 * Absolute ceiling is the altitude at which the airplane has a maximum rate of climb of zero, it can no longer perform a steady climb
 * Maximum power excess is zero at this altitude
 * Service ceiling is the altitude that an airplane can maintain a maximum rate of climb of only 100 f.p.m.
 * Cruise ceiling is the altitude that an airplane can maintain a maximum climb rate of only 300 f.p.m.
 * Combat ceiling is the altitude that an airplane can maintain a maximum climb rate of 500 f.p.m.
 * Maximum operating ceiling is the maximum altitude at which an aircraft can be operated
 * The maximum operating ceiling of the T-34 and the T-37 is 25,000 feet
 * Maximum glide range is the maximum distance the airplane can glide to reach a safe landing area after the engine has stalled
 * Maximum glide endurance is the amount of time an airplane can glide and is used if the engine stalls in easy reach of a safe landing area
 * Maximum glide range is achieved at L/DMAX velocity and L/DMAX AOA
 * Maximum glide endurance is achieved at less than L/DMAX velocity and at an angle of attack greater than L/DMAX AOA
 * Increasing weight will cause the airplane to fly faster and glide faster, but still glide the same distance
 * Increasing altitude will increase the glide endurance and range
 * Changing configuration will decrease the glide rate and endurance
 * Headwinds will cause a decrease in glide range
 * Tailwinds will cause an increase in glide range
 * Winds have no effect on range or endurance
 * Propeller feathering will increase glide range and endurance and increase airspeed
 * The region of normal command is located at velocities above maximum endurance
 * Characterized by airspeed stability
 * The region of reverse command is located at velocities below maximum endurance
 * Characterized by airspeed instability
 * In the region of normal command, velocity and throttle setting for level flight are directly related
 * To fly in equilibrium at a faster airspeed, you need more TA/PA than you did at lower airspeed, to fly slower you need less TA/PA

AIRCRAFT CONTROL SYSTEMS
ELO 1.116 State the type of control system used in the T-34 or T-37. ELO 1.117 Describe how the control surfaces respond to control inputs. ELEVATOR AILERONS SPOILERS RUDDER ELO 1.118 Describe how the trim tab system holds an airplane in trimmed flight. ELO 1.119 State the T-34 trim requirements for various conditions of flight. ELO 1.120 State the point around which control surfaces are balanced. ELO 1.121 Define mass balancing and aerodynamic balancing. MASS BALANCING AERODYNAMIC BALANCING ELO 1.122 State the methods of mass balancing and aerodynamic balancing used by each control surface on the T-34. ELO 1.123 Describe how trim tabs can provide artificial feel. ELO 1.124 State the purpose of bobweights and downsprings. BOBWEIGHTS DOWNSPRINGS ELO 1.125 State the artificial feel devices used by each control surface on the T-34.
 * Trim tabs are the control system used on the T-34 and T-37
 * The elevator is attached to the trailing edge of the horizontal stabilizer, and controls the pitching moment around the airplane’s center of gravity (CG)
 * The ailerons move in unison opposite from one another
 * If the stick is pushed left the left aileron rises and the right aileron lowers
 * Spoilers may be attached to the wing’s upper surface to provide roll control on some aircraft
 * Disrupt the airflow over the wing in order to decrease the lift on the wing
 * The rudder is attached to the trailing edge of the vertical stabilizer and produces a yawing action
 * Trimming reduces the force required to hold control surfaces in a position necessary to maintain a desired flight attitude
 * Trim tabs must be moved in the opposite direction as the control surface
 * Aileron trim in the T-34 is adjusted after takeoff and seldom requires further adjustment during flight
 * Right rudder trim is required for power increases and slower airspeeds
 * Left rudder trim is required for power reductions and faster airspeeds
 * Elevator trim is adjusted up at slower speeds and down at higher speeds
 * All surface’s center of gravity and aerodynamic center must be balanced around the hingeline in order to regulate control pressure, prevent control flutter, and provide control-free stability
 * Mass balancing is a technique used to locate the CG on the hingeline in which weights are placed inside the control surface in the area forward of the hingeline (shielded horn and overhang)
 * Aerodynamic balancing uses shield horns on the elevator and rudder, and an overhang on the ailerons
 * For aerodynamic balance, the T-34 uses shielded horns on the elevator and rudder, and an overhang on the ailerons
 * For mass balance, the T-34 uses weights placed on the inside of the control surface in the area forward of the hingeline
 * Servo trim tabs move in the opposite direction as the aileron, thus helping the pilot to deflect the aileron, and making the airplane easier to maneuver
 * Anti-servo trim tabs move in the same direction at a faster rate, thus the more that the rudder is pressed, the greater the resistance that the pilot will feel
 * Neutral trim tabs use a constant angle to the elevator when the control surface is deflected
 * Bobweights increase the force required to pull the stick aft during maneuvering flight
 * Downsprings increase the force required to pull the stick aft at low airspeeds
 * The T-34 uses trim tabs, downsprings, and bobweights to provide artificial feel to the aircraft

STABILITY
ELO 1.126 Define static stability and dynamic stability. STATIC STABILITY DYNAMIC STABILITY ELO 1.127 Identify the stability conditions of various systems based on their tendencies and motion. POSITIVE STATIC STABILITY NEGATIVE STATIC STABILITY NEUTRAL STATIC STABILITY ELO 1.128 Explain the relationship between stability and maneuverability. ELO 1.129 State what may be done to increase an airplane’s maneuverability. ELO 1.130 Define longitudinal stability and neutral point. LONGITUDINAL STABILITY NEUTRAL POINT ELO 1.131 Explain the contribution of straight wings, wing sweep, fuselage, horizontal stabilizer, and neutral point location to longitudinal static stability. STRAIGHT WINGS WING SWEEP FUSELAGE HORIZONTAL STABILIZER NEUTRAL POINT LOCATION ELO 1.132 Define directional stability, sideslip angle, and sideslip relative wind. DIRECTIONAL STABILITY SIDESLIP ANGLE SIDESLIP RELATIVE WIND ELO 1.133 Explain the contribution of straight wings, swept wings, fuselage, and vertical stabilizer to directional static stability. STRAIGHT WINGS SWEPT WINGS FUSELAGE VERTICAL STABILIZER ELO 1.134 Define lateral stability. LATERAL STABILITY ELO 1.135 Explain the contribution of dihedral and anhedral wings, wing placement on the vertical axis, swept wings, and the vertical stabilizer to lateral static stability. DIHEDRAL WINGS ANHEDRAL WINGS WING PLACEMENT ON THE VERTICAL AXIS SWEPT WINGS VERTICAL STABILIZER ELO 1.136 Describe directional divergence, spiral divergence, dutch roll, and phugoid motion. DIRECTIONAL DIVERGENCE SPIRAL DIVERGENCE DUTCH ROLL PHUGOID MOTION ELO 1.137 State the stability conditions that produce directional divergence, spiral divergence, dutch roll, and phugoid motion. DIRECTIONAL DIVERGENCE SPIRAL DIVERGENCE DUTCH ROLL PHUGOID MOTION ELO 1.138 Describe proverse roll, adverse yaw, and pilot induced oscillations. PROVERSE ROLL ADVERSE YAW PILOT INDUCED OSCILLATIONS ELO 1.139 Explain how pilot induced oscillations relate to the T-34C or T-37B. ELO 1.140 Describe the effects of asymmetric thrust, propeller slipstream swirl, P-factor, torque, and gyroscopic precession as they apply to the T-34C or T-37B. ELO 1.141 Describe what must be done to compensate for asymmetric thrust, propeller slipstream swirl, P-factor, torque, and gyroscopic precession as they apply to the T-34C and T-37B.
 * Static stability is the initial tendency of an object to move toward or away from its original equilibrium position
 * Dynamic stability is the position with respect to time, or motion of an object after a disturbance
 * Positive static stability is when an object has an initial tendency towards its original equilibrium position
 * Negative static stability is when an object has an initial tendency away from equilibrium following a disturbance
 * Neutral static stability is when the initial tendency is to accept the displacement position as the new equilibrium position
 * Stability and maneuverability are opposites
 * One way to increase maneuverability is to give the airplane weak stability
 * This makes the airplane more difficult to fly in equilibrium and will require more of the pilots attention
 * The second way to increase maneuverability is to give the airplane larger control surfaces
 * The larger surfaces create larger moments resulting in greater aerodynamic forces
 * Longitudinal stability is the stability of the longitudinal axis around the lateral axis
 * The neutral point is the location of the CG of an airplane, along the longitudinal axis, that would produce neutral longitudinal static stability
 * The average aerodynamic center for the overall airplane
 * Straight wings are negative contributors to longitudinal static stability
 * Sweeping the wings back is a positive contributor to longitudinal static stability
 * The fuselage is a negative contributor to longitudinal static stability
 * The horizontal stabilizer will have the greatest positive effect on longitudinal static stability
 * If the neutral point location is behind the airplane’s center of gravity the component will be a positive contributor to longitudinal static stability
 * If the neutral point location is in front of the airplane’s center of gravity the component will be a negative contributor to longitudinal static stability
 * Directional stability is the stability of the longitudinal axis around the vertical axis
 * Sideslip angle is the angle between the longitudinal axis and the relative wind
 * Sideslip relative wind is the component of the relative wind that is parallel to the lateral axis
 * Straight wings have a small positive effect on directional static stability
 * Swept wings will have a positive effect on directional static stability
 * The fuselage is a negative contributor to the airplane’s directional static stability
 * The vertical stabilizer is the greatest positive contributor to the directional static stability of a conventionally designed airplane
 * Lateral stability is the stability of the lateral axis around the longitudinal axis
 * Dihedral wings are the greatest positive contributors to lateral static stability
 * Anhedral wings are the greatest negative contributors to lateral static stability
 * A high mounted wing is a positive contributor to lateral static stability
 * A low mounted wing is a negative contributor to lateral static stability
 * Swept wings are laterally stabilizing
 * When in a lateral sideslip, the vertical stabilizer senses an angle of attack, so it produces lift
 * Since the tail is above the airplane’s CG, this lift produces a moment that tends to right the airplane
 * Directional divergence is a condition of flight in which the reaction to a small initial sideslip results in an increase in sideslip angle
 * Directional divergence is caused by negative directional static stability
 * Spiral divergence occurs when an airplane has strong directional stability and weak lateral stability
 * Dutch roll is the result of strong lateral stability and weak directional stability
 * Oscillations of altitude and airspeed that occur over relatively long periods of time, and are easily controlled by the pilot
 * Also called phugoid motion
 * Directional divergence occurs at negative directional static stability
 * Spiral divergence occurs at strong directional stability and weak lateral stability
 * Dutch roll occurs at strong lateral stability and weak directional stability
 * Phugoid motion occurs when an upward gust of air strikes the airplane causing a gain in altitude but a loss in airspeed
 * Proverse roll is the tendency of an airplane to roll in the same direction as it is yawing
 * Adverse yaw is the tendency of an airplane to yaw away from the direction of aileron roll input
 * Pilot induced oscillations are short period oscillations of pitch altitude and angle of attack
 * The T-34C and T-37B are not subject to pilot induced oscillations since it does not have strong longitudinal static stability
 * Asymmetric thrust can occur in the T-37B as the engines are relatively close together and is corrected by full opposite rudder for the yawing and opposite aileron for the proverse roll
 * Slipstream swirl occurs from corkscrewing of air and is corrected in the T-34C by increasing right rudder and lateral control stick inputs
 * P-factor is caused by one propeller creating more thrust than the other, happens in the T-37B
 * Torque occurs in the T-34C and is corrected by elevator trim tabs
 * Gyroscopic precession occurs in the T-34C by pitching the nose upwards to produce an applied force acting forward on the bottom of the propeller disk and causes the T-34 to yaw right
 * Gyroscopic precession occurs in the T-37B from its engine compressors and turbines, so pitching the nose up will tend to yaw the T-37B to the left
 * Asymmetric thrust can occur in the T-37B as the engines are relatively close together and is corrected by full opposite rudder for the yawing and opposite aileron for the proverse roll
 * Slipstream swirl occurs from corkscrewing of air and is corrected in the T-34C by increasing right rudder and lateral control stick inputs
 * P-factor is caused by one propeller creating more thrust than the other, happens in the T-37B
 * Torque occurs in the T-34C and is corrected by elevator trim tabs
 * Gyroscopic precession occurs in the T-34C by pitching the nose upwards to produce an applied force acting forward on the bottom of the propeller disk and causes the T-34 to yaw right
 * Gyroscopic precession occurs in the T-37B from its engine compressors and turbines, so pitching the nose up will tend to yaw the T-37B to the left

SPINS
ELO 1.142 Define spin and autorotation. SPIN AUTOROTATION ELO 1.143 Identify the factors that cause a spin. ELO 1.144 Identify the effects of weight, pitch attitude, and gyroscopic effect on spin entry. WEIGHT PITCH ATTITUDE GYROSCOPIC EFFECT ELO 1.145 Describe the angles of attack and forces on each wing that cause autorotation during a spin. ELO 1.146 State the characteristics and cockpit indications of normal and inverted spins. ERECT SPINS INVERTED SPINS ELO 1.147 Identify the effects of control inputs on spin recovery. ELO 1.148 State how the configuration of the empennage and placement of the horizontal control surfaces can affect spin recovery. ELO 1.149 Describe the steps in the spin prevention procedure for the T-37 and the spin recovery procedures for the T-34 and T-37. ELO 1.150 Define progressive and aggravated spin. PROGRESSIVE SPIN AGGRAVATED SPIN
 * A spin is an aggravated stall that results in autorotation
 * Autorotation is a combination of roll and yaw that propagates itself and progressively gets worse due to asymmetrically stalled wings
 * A spin is only caused by a stalling airplane with some form of yaw introduced
 * Weight located far from the CG causes a greater moment of inertia and makes the spin difficult to overcome
 * Increased weight causes a more difficult time for the pilot to recover from the spin
 * Pitch attitude will have a direct impact on the speed the aircraft stalls
 * The higher the pitch attitude, the greater the vertical component of thrust, and the lower the stall speed
 * Spins are entered slower and with less oscillations at high attitude
 * Spins are entered faster and with more oscillations at low attitude
 * The nose will tend to drift the direction of the rotation of the propeller due to gyroscopic precession
 * Autorotation is a combination of roll and yaw that propagates itself and progressively gets worse due to asymmetrically stalled wings
 * The up-going wing has a lower AOA
 * The down-going wing has a higher AOA
 * The up-going wing has a greater CL due to its smaller AOA resulting in increased lift
 * The down-going wing has a greater CD due to its increased AOA
 * Erect spins result from positive-g stall entries
 * The altimeter will be rapidly decreasing, the turn needle will be pegged in the direction of the spin, the gyro may be tumbling
 * The balance ball (slip indicator) gives no useful indication of spin direction and should be disregarded
 * Inverted spins result from either negative-g stalls or an improperly applied recovery from an erect spin that results in a negative-g stall
 * The altimeter will be rapidly decreasing, the turn needle will be pegged in the direction of the spin, gyro may be tumbling
 * The rudder is the principal control for stopping autorotation
 * The horizontal component creates a force that opposes yawing and the vertical component creates a force that pulls the tail up and pitches the nose down
 * Opposite rudder maximizes both of these components
 * The empennage has two ventral fins located below it that decrease the spin rate and aid in maintaining a nose-down attitude
 * The placement of the horizontal control surfaces will significantly affect spin recovery
 * To initiate the spin prevention, use stick forces as necessary to break the stall, apply rudder as necessary to eliminate the yaw, and check the throttles at idle
 * Move the controls positively until the recovery is made
 * Both the stick and rudder should be positively moved against the spin with continuous control movement until the rotation stops
 * Do not hesitate to use the necessary controls, it may take full control deflection
 * Progressive spin is when you reverse the spin direction
 * Characterized by a violent entry which can be disorienting
 * Aggravated spin results from pushing the stick forward while maintaining rudder in the direction of the spin
 * Characterized by an increased spin rate and a steep nose-down pitch

TURNING FLIGHT
ELO 1.151 Describe how the forces acting on an airplane produce a level coordinated turn. ELO 1.152 Define load factor. LOAD FACTOR (n) ELO 1.153 Describe the relationship between load factor and angle of bank for level flight. ELO 1.154 State the effect of maneuvering on stall speed. ELO 1.155 Define load, strength, static strength, static failure, fatigue strength, fatigue failure, service life, creep, limit load factor, elastic limit, overstress/over-g, and ultimate load factor. LOAD STRENGTH STATIC STRENGTH STATIC FAILURE FATIGUE STRENGTH FATIGUE FAILURE SERVICE LIFE CREEP LIMIT LOAD FACTOR ELASTIC LIMIT OVERSTRESS/OVER-G ULTIMATE LOAD FACTOR ELO 1.156 State the relationship between the elastic limit and the limit load factor. ELO 1.157 Describe and identify the parts of the V-n/V-g diagram, including the major axes, limit load factor, ultimate load factor, maneuvering speed, cornering velocity, redline airspeed, accelerated stall lines, and the safe flight envelope. ELO 1.158 List and describe the phenomena that are used to determine redline airspeed. ELO 1.159 State the limit load factors, maneuvering speed, and redline airspeed for the T-34 or T-37. ELO 1.160 Describe the effects of weight, altitude, and configuration on the safe flight envelope. WEIGHT ALTITUDE CONFIGURATION ELO 1.161 Define asymmetric loading and state the limitations. ASYMMETRIC LOADING ELO 1.162 Define gust loading. GUST LOADING ELO 1.163 State what should be done not to exceed the limit load factor in moderate turbulence. ELO 1.164 Define turn radius and turn rate. TURN RADIUS (r) TURN RATE (w ) ELO 1.165 State the effect of velocity, angle of bank, weight, slipping, and skidding on turn rate and turn radius. VELOCITY ANGLE OF BANK WEIGHT SLIPPING SKIDDING ELO 1.166 Define standard rate turn. STANDARD RATE TURN (SRT) ELO 1.167 State the approximate angle of bank for a standard rate turn in the T-34 or T-37. ==TAKEOFF/LANDING PERFORMANCE, WAKE TURBULENCE AND WIND SHEAR== ELO 1.168 Define takeoff and landing speeds. ELO 1.169 State the factors affecting the takeoff and landing speeds. ELO 1.170 Describe the effects on true airspeed, indicated airspeed, and ground speed for takeoff and landing due to variations in weight, density, and high lift devices, and wind. ELO 1.171 Describe the forces acting on an airplane during takeoff and landing. ELO 1.172 State the factors affecting takeoff and landing distance. ELO 1.173 Describe the effects on takeoff and landing distance due to variations in weight, altitude, temperature, humidity, high lift devices, and wing. ELO 1.174 Describe how crosswinds affect an airplane during takeoff and landing. ELO 1.175 Describe how runway alignment is maintained during a crosswind takeoff or landing. ELO 1.176 Define ground effect. GROUND EFFECT ELO 1.177 Describe the effects of ground effect on lift and drag. ELO 1.178 State when the T-34 or T-37 will be in ground effect. ELO 1.179 State the preferred method used to stop an airplane that is hydroplaning. ELO 1.180 State the cause of wingtip vortices. ELO 1.181 State how interference between airplanes in flight affects the aerodynamic forces acting on each airplane. ELO 1.182 State the airplane configuration when vortex strength is greatest. ELO 1.183 Identify the hazards of encountering another aircraft’s wake turbulence. ELO 1.184 Identify the appropriate wake turbulence avoidance procedures. ELO 1.185 Define wind shear. WIND SHEAR ELO 1.186 Identify the causes of wind shear. ELO 1.187 Identify the hazards associated with wind shear during takeoff and landing.
 * In a turn, only the vertical component of the lift vector opposes weight
 * If the pilot does not increase the total lift vector, the airplane will lose altitude because weight will be greater than LV
 * The increased lift is normally achieved by increasing the AOA, that is, pulling back on the stick
 * Load factor is the ratio of the total lift to the airplane’s weight
 * Often referred to as g’s as it is the number of times the earth’s gravitational pull that the pilot feels
 * Load factor is equal to the lift divided by the weight of the airplane
 * Equation is given as n = L/W
 * Stall speed increases when we induce a load factor greater than one on the airplane
 * A load is a stress-producing force that is imposed upon an airplane or component
 * Strength is a measure of a material’s resistance to load
 * Static strength is a measure of a material’s resistance to a single application of a steadily increasing load or force
 * Static failure is the breaking of a material due to a single application of a steadily increasing load or force
 * Fatigue strength is a measure of a material’s ability to withstand a cyclic application of load or force
 * Fatigue failure is the breaking of a material due to cyclic application of load or force
 * Service life is the number of applications of load or force that a component can withstand before it has the probability of failing
 * Creep is when a metal is subjected to high stress and temperature it tends to stretch or elongate
 * Limit load factor is the greatest load factor an airplane can sustain without any risk of permanent deformation
 * The elastic limit is the maximum load that may be applied to a component without permanent deformation
 * Overstress/over-g is the condition of possible permanent deformation or damage that results from exceeding the limit load factor
 * Ultimate load factor is the maximum load factor that the airplane can withstand without structural failure
 * The limit load factor is designed to be less than the elastic limit of individual components
 * The V-n/V-g diagram is a graph that summarizes an airplane’s structural and aerodynamic limitation
 * Horizontal axis is the indicated airspeed
 * Vertical axis is the load factor, or g’s
 * Accelerated stall lines represent the maximum load factor that an airplane can produce based on airspeed
 * The maneuver point is the point where the accelerated stall line and the limit load factor line intersect
 * Redline airspeed is the maximum airspeed your airplane is allowed to fly
 * Redline airspeed (VNE) is determined by one of several methods: MCRIT, airframe temperature, excessive structural loads, or controllability limits
 * MCRIT is the critical mach number, redline airspeed is just below this speed
 * Airframe temperature can heat up with friction from particles in the air resulting in creep
 * Excessive structural loads may be encountered on components other than main structural members
 * Controllability limits occur at high airspeeds where dynamic pressure affects the airplane’s performance
 * The redline airspeed for the T-34 is 280 KIAS and for the T-37 is 382 KIAS
 * The maneuver speed for the T-34 is 135 KIAS and for the T-37 is 235 KIAS
 * The limit load factors for the T-34 are excessive horizontal stabilizer loads at speeds in excess of 280 KIAS
 * With decreasing weight, the limit load factor increases
 * With an increase in altitude, the indicated redline airspeed must decrease to keep the airplane below MCRIT
 * Lowering the landing gear and flaps substantially reduces the safe flight envelope
 * Asymmetric loading refers to uneven production of lift on the wings of an airplane
 * Caused by a pullout, trapped fuel, or hung ordinance
 * The limit load factor due to pilot induced loads should be reduced to approximately two-thirds of the normal limit load factor
 * Gust loading refers to the increase in the G load due to vertical wind gusts
 * The limit load factor due to pilot induced loads should be reduced to approximately two-thirds of the normal limit load factor
 * Flying at maneuver speed will not allow the airplane to be overstressed for positive g’s at that airspeed
 * Turn radius is a measure of the radius of the circle the flight path scribes
 * Turn rate is the rate of heading change, measured in degrees per second
 * As velocity increases for a given angle of bank, turn rate will decrease and turn radius will increase
 * Increasing angle of bank for a given velocity will increase turn rate and decrease turn radius
 * Turn rate and radius are independent of weight
 * Slipping will cause the turn radius to increase and the turn rate to decrease
 * Skidding will cause the turn radius to decrease and the turn rate to increase
 * A standard rate turn is one in which three degrees of turn are completed each second
 * For a standard rate turn in a T-34, the angle of bank should be equal to 15-20 percent of airspeed
 * For a standard rate turn in a T-37, the angle of bank should be equal to 30 percent of airspeed
 * A standard rate turn is equal to two needle widths deflection on the turn needle in the T-34 and T-37
 * The minimum takeoff speed is about 20 percent above the power-off stall speed, while the landing speed is about 30 percent higher
 * High lift devices are often used to decrease takeoff and landing speeds
 * Indicated airspeed for takeoff and landing will not be affected by changes in air density
 * Indicated airspeed for takeoff and landing will not be affected by changes in air density
 * High lift devices decrease airspeed
 * Increased weight will decrease ground speed
 * Headwind will decrease ground speed
 * Tailwinds will increase ground speed
 * Rolling friction occurs on takeoff and accounts for the friction between the landing gear and the runway
 * The coefficient of friction is dependent upon runway surface, runway condition, tire type and degree of brake application
 * The net accelerating force is equal to thrust minus drag minus rolling friction
 * The net decelerating force is equal to drag plus rolling friction minus thrust
 * Weight is the greatest factor affecting takeoff distance
 * Using high lift devices decreases the takeoff distance
 * Three density factors, high, hot, humid make for poor takeoff and landing conditions
 * Weight increases takeoff and landing distance
 * Temperature, altitude, and humidity all increase proportionally with takeoff and landing distance
 * High lift devices decrease takeoff distance
 * Headwinds decrease takeoff distance
 * Tailwinds increase takeoff distance
 * Greater wing area decreases landing and takeoff distance
 * Crosswinds affect directional control of an airplane
 * Ailerons are used to overcome lateral stability that is trying to roll the airplane away from the sideslip relative wind
 * The nosewheel will only be lifted above the minimum nosewheel liftoff/touchdown speed to prevent the airplane from weathercocking or weathervaning into the wind and possibly running off the runway
 * Ground effect significantly reduces induced drag and increases effective lift when the airplane is within one wingspan of the ground
 * Ground effect reduces induced drag and increases effective lift
 * The aircraft is in ground effect within one wingspan of the ground, 33 feet for the T-34 or T-37
 * Beta setting should be used as much as possible to stop the aircraft that is hydroplaning
 * Wingtip vortices are spiraling masses of air that are formed at the wingtip when an airplane produces lift
 * The most significant factor affecting your ability to counteract the roll induced by vortices is the relative wingspan between the two airplanes
 * Vortices are generated from the time an airplane rotates for takeoff until the airplane nosewheel touches down for landing
 * The greatest vortex strength occurs when the generating airplane is heavy, slow, and clean
 * Hazards associated with encountering another aircraft’s wake turbulence are possible over g or a flameout
 * The most important pilot technique for survival during wake turbulence is to avoid it
 * Remain two minutes behind the aircraft in front of you
 * Fly slightly above the aircraft in front of yours flight path
 * Land slightly beyond the touchdown point of the aircraft in front of you
 * Wind shear is the sudden change in wind direction and/or speed over a short distance in the atmosphere
 * Most often caused by jet streams, land or sea breezes, fronts, inversions and thunderstorms
 * Wind shear is most often caused by jet streams, land or sea breezes, fronts, inversions and thunderstorms
 * Airspeed can increase or drop rapidly through wind shear
 * The possibility of a stall becomes very real with an increased angle of attack
 * Transition from tailwinds to no winds cause an increase in performance
 * Transition from headwinds to no winds cause a decrease in performance
 * Pilot may have insufficient time to correct the situation and could fall short of the runway

=T-34C Characteristics:=

Physical Fuselage type : semi-monocoque 28ft  8in Landing gear : tricycle Wing type : cantilever Dihedral angle : 7 deg AOI : 4 deg Flap type : slotted Geometric twist : 3.1 deg Prop type : variable pitch

Flight CLMAX AOA : 29 to 29.5 units Stall warning : buffeting, rudder shakers, AOA indexer, AOA indicator

Performance Engine type : PT6A-25 Sea level flat rating :			550 SHP 	1315 ft lb torque Navy limited sea level rating : 	425 SHP	1015

=Practice Exams= You can download a zip file. of the exams. It would be nice if somone felt like typing them up on here so people don't have to download and try to read these scans.

AERODYNAMICS MIDTERM EXAM 3

Basic Properties of Physics

1.     What is the definition of power?

a.   The ability to do work. b.   Work done per unit of time. c.   Energy due to motion. d.   Mass times acceleration.

2.     What is the definition of density?

a.   force per unit area b.   mass per unit volume c.   mass times gravity d.   mass times velocity squared

3.     What is an example of an aircraft operating under Newton's Law of Equilibrium?

a.   An aircraft making a turn while maintaining a constant true airspeed (TAS) and altitude. b.   An aircraft maintaining straight and level flight at constant true airspeed (TAS). c.   An aircraft pulling out of a dive at a constant true airspeed (TAS). d.   An aircraft accelerating in level flight due to an increase in thrust.

4.     How does an increase in altitude affect static pressure?

a.   Increase b.   Remains the same c.   Decreases

5.     What would cause an increase in the density of air?

a.   Increase in altitude b.   Decrease in pressure c.   Increase in temperature d.   Decrease in altitude

6.     What air property is the Greek letter p (rho) used to represent?

a.   Density b.   Temperature c.   Pressure d.   Viscosity

7.     What affect does an increase in altitude have on the speed of sound and why?

a.   Increase due to decrease in temperature b.   Decrease due to decease in density c.   Increase due to decrease in pressure d.   Decrease due to decrease in temperature

8.     What atmospheric conditions would provide the greatest air density?

a.   Hot temperature, low static pressure, low humidity b.   Hot temperature, low static pressure, high humidity c.   Cold temperature, low static pressure, high humidity d.   Cold temperature, high static pressure, low humidity

Airplane Terminology

9.     What are the five major components of an airplane?

a.   Wings, fuselage, empennage, landing gear, and engine. b.   Wings, cockpit, empennage, flaps, and engine. c.   Fuselage, rudder, empennage, ailerons, and engine. d.   Fuselage, empennage, engine/transmission assembly, vertical stabilizer, and tail rudder.

10.   Pitch is defined as the motion of the longitudinal axis about what axis?

a.   longitudinal axis b.   lateral axis c.   vertical axis d.   horizon

11.   All motion or changes in aircraft attitude ocurs about which position?

a.   Aerodynamic Center (AC). b.   Center of pressre (CP). c.   Center of gravity (CG). d.   The cockpit.

12.   What control surface is used for longitudinal control?

a.   rudder b.   elevators c.   ailerons d.   flaps

13.   The wings of the T-34 are tapered to

a.   increase weight, improve structural stiffness, and reduce wing tip vortices b.   decrease weight, improve structural stiffness, and reduce wing tip vortices c.   decrease weight, remove structural stiffness, and reduce wing tip vortices d.   increase weight, improve structural stiffness, and increase wing tip vortices.

14.   What control surfaces control roll?

a.   elevators b.   rudder c.   control stick d.   ailerons

15.   Aspect ratio (AR) is

a.   the ratio of the wingspan to the tip chord (Ct). b.   the ratio of the root chord (Cr) to the tip chord (Ct). c.   the ratio of the wingspan to the average chord (c). d.   the ratio of the wingspan to the root chord (Cr).

16.   The fuselage construction of the T-34 is:

a.   full cantilever b.   full monocoque c.   semi-monocoque d.   papier-maché

Basic Aerodynamic Principles

17.   What four airflow properties must remain constant at a given point on an airfoil to have steady airflow?

a.   Viscosity, temperature, pressure, density b.   Velocity, temperature, pressure, density c.   Lift, weight, thrust, drag d.   Friction, viscosity, density, lift

18.   What is the continuity equation for incompressible airflow?

a.   F = m x a         b.    A1V1 = A2V2 c.   Ht = q + P3         d.    q = 1/2pV^2


 * page missing sorry! ****

Lifts and Stalls

25.  What is the angle formed between the chordline of an airfoil and the relative wind?

a.   Angle of attack b.   Angle of incidence c.   Pitch angle d.   Sideslip angle

26.   What is the static pressure distribution about a positively cambered airfoil at zero angle of attack in level flight?

a.   The static pressure distribution is equal over all portions of the airfoil. b.   The static pressure distribution is less over the upper surface of the airfoil. c.   The static pressure distribution is less over the lower surface of the airfoil. d.   The atmospheric static pressure at aircaft altitude is equal to the static pressure distribution over the upper surface of the airfoil.

27.   What is the aerodynamic lift equation?

a.   L = qSCr b.   L = qSCL c.   L = qSCd d.   L = qSCmacC

28.   What must a pilot do to accelerate an aircraft, yet maintain a constant altitude?

a.   Add thrust and decrease lift as true airspeed increases. b.   Add thrust and increase angle of attack as true airspeed increases. c.   Add thust and decrease angle of attack as true airspeed increases. d.   Reduce thrust and increase angle of attack as true airspeed increases.

29.   What is the cause of a stall if an aircraft rolls into a 60 degree angle of bank turn and pulls 3 g's at 200 knots?

a.   Excessive angle of bank b.   Excessive g loading c.   Excessive airspeed d.   Excessive angle of attack

30.   According to the lift equation, in a slow speed condition such as landing, the angle of attack will be

a.   smaller than at cruising because we need less lift b.   larger than at cruising in order to maintain same lift at slower velocities c.   dependent upon drag d.   none of the above

31.   (BAD QUESTION?) The coefficient of lift

a.   decreases from stalling angle of attack to cruising angle of attack b.   depends on angle of attack and shape of the airfoil c.   is a dimensionless number d.   all of the above

32.   How do you compute the Aerodynamic Surface Area (Wing Surface Area)?

a.   Divide the wing span by average chord b.   Multiply wing span by average chord c.   Squaring the average chord d.   Squaring the wing span

33.   What type of airflow and associated energy levels comprise the boundary layer?

a.   The boundary layer has high energy laminar airflow. b.   The boundary layer has low energy turbulent airflow. c.   The boundary layer is comprised of both laminar and turbulent airflow with the laminar airflow having the highest energy level. d.   The boundary layer is comprised of both laminar and turbulent airflow with the turbulent airflow having the highest energy level.

34.   Which of the Following are two types of BLC devices?

a.   fixed slots and regulated slots b.   fixed slots and automatic slots c.   broken slots and fixed slots d.   intermittent slots and fixed slots

Drag and Wake Turbulence

35.   Drag is

a.   parallel to the chordline b.   parallel to the thrust vector c.   perpendicular to the lift vector d.   parallel to the center line of the fuselage

36.   Airfoil efficiency at various angles of attack is expressed by the ratio of

a.   Lift to dynamic pressure b.   Lift to drag c.   Lift to weight d.   Lift to velocity

37.   High induced drag is associated with low angles of attack

a.   True b.   False

38.   Parasite drag always decreases with increase in velocity

a.   True b.   False

39.   L/D Maximum AOA is equivalent to all but which of the following?

a.   Minimum drag AOA b.   AOA where parasite drag equals induced drag c.   Maximum lift AOA d.   Wing's most efficient AOA

40.   What change in induced drag occurs as airfoil angle of attack increases in a stall?

a.   Induced drag increases as lift decreases b.   Induced drag decreases as lift decreases c.   Induced drag remains constant as lif decreases

41.   Vortices may instantly change the direction of the

a.   crosswind b.   headwind c.   relative wind d.   they don't make any changes

42.   Small airplanes have nothing to worry about when operating within three rotor diameters of any hovering helicopter.

a.   True b.   False

Thrust and Power

43.   Thrust required refers to

a.   the amount of thrust that is required to overcome drag b.   the amount of thrust needed to reduce drag c.   the amount of thrust needed to maintain a constant speed when flying into a headwind. d.   The amount of thrust needed to lift the weight of the airplane.

44.   To find power required

a.   multiply thrust required by drag b.   mulitply thrust required by velocity c.   divide thrust required by drag d.   divide thrust required by velocity

45.   As the throttle is retarded, thrust available

a.   Decreases b.   Increases c.   Remains constant 46.   In a turboprop engine, its output is called

a.   propeller efficiency (p.e.) b.   thrust horsepower (THP) c.   shaft horsepower (SHP) d.   horsepower

47.   Thrust horsepower refers to

a.   engine output b.   propeller output c.   the torque produced by the engine d.   none of the above

48.   The T-34's greatest maintainable aispeed without descending is

a.   490 KIAS at sea level b.   390 KIAS at sea level c.   190 KIAS at sea level d.   90 KIAS at sea level

49.   If a plane is in equilibium level flight at a constant angle of attack, an increase in weight requires

a.   a decrease in thrust required b.   an increase in thrust required c.   decrease in power required d.   decrease in power avaliable

50.   With an increase in altitude, the power required curve shifts

a.   up and right b.   down and right c.   up and left d.   to the right only

ANSWERS:

1. B

2. B

3. B

4. C

5. D

6. A

7. D

8. D

9. A

10. B

11. C

12. B (Assignment sheet 1-2-3 question 6)

13. B

14. D

15. C

16. C

17. B

18. B

25. A

26. B

27. B

28. C

29. D

30. B

31. D (no answer given, my personal guess)

32. B

33. C (D is the correct answer, turbulent BL has more energy than laminar)

34. B

35. C

36. B

37. B

38. B (scan says A but if you look at the graph in the book that is wrong)

39. C

40. B (again scan says A but if you look at the equation induced drag has to decrease if lift decreases)

41. C

42. B

43. A

44. B

45. A

46. A (This is wrong, output of turboprop engine is SHP (c))

47. B

48. C

49. B

50. A