This situation happens every time the helicopter's main rotor is at rest. Rotor coning Rotor droop Rotor tracking Feathering.
What is the primary factor in determining calibrated airspeed? Instrument error Tailwind Headwind Density.
Which of the following factors will lead to an increase of ground distance during a glide?
Increase in airplane's weight Decrease the airplane's gross weight By means of the presence of headwind By means of the presence of tailwind.
For best maximum endurance, an airplane should have the following characteristics except flight at altitude highest propeller efficiency highest fuel weight lowest specific consumption.
Which of the following is true regarding radius of turn during level coordinated flight?
The greater the weight, the wider the turn will be. The greater the angle of bank, the wider the turn will
be. The greater the wing area, the wider the turn will be. The higher the angle of attack, the wider the turn will
be.
The total pressure is: can be measured in a small hole in a surface, parallel
to the local stream. ½ρV2 static pressure minus the dynamic pressure. static pressure plus the dynamic pressure.
The power required curves for an increase in altitude show that the: PR remains the same as altitude increases PR increases by the same amount as the velocity PR increases but the velocity does not PR decreases by the same amount as the velocity.
In order to overcome induced drag, power required varies: inversely with v inversely with v^3 directly with v^2 inversely with v^2.
Why should flight speeds above VNE be avoided? Control effectiveness is impaired that the aircraft is
uncontrollable Excessive induced drag will result in structural failure Design limit load factors may be exceeded, if gusts
are encountered A high speed stall is most likely to occur.
When the reynold's number is above 4000 the flow is Laminar Critical flow Supersonic Turbulent.
When the reynold's number is below 2300 the flow is Laminar Critical flow Supersonic Turbulent.
What must you do to remain in formation as your aircraft takes on fuel (increasing weight) from the tanker that is maintaining a constant altitude and true airspeed? Decrease AOA and increase TAS Maintain a constant AOA and TAS Increase AOA and TAS Increase AOA and maintain constant TAS.
If an airplane in flight is disturbed from equilibrium and has the tendency to return to equilibrium,
directional static stability exists neutral static stability exists positive static stability exists negative static stability exists.
Which of the following statements is true about airfoil thickness? Critical Mach number increases as the thickness of
the airfoil increases None of the Above Critical Mach number decreases as thickness
decreases Critical Mach number has nothing to do with airfoil
thickness.
The location of aerodynamic center for usual subsonic airfoils can normally be found at (where c = chord)
near c/2 as angle of attack decreases c/4 regardless of angle of attack near c/4 as angle of attack decreases it ranges from c/4 to c/2 regardless of angle of
attack.
What is the relationship between drag coefficient and lift coefficient? Cd = Cl² Cd = 2Cl 2Cd = 2Cl Cd² = Cl.
What is the value of pressure coefficient at low speeds? Cpo > Cp Cpo < Cp Cpo = Cpcr Cpo = Cp.
What happens to the value of lift as velocity is doubled? lift is doubled lift is reduced by half lift is quadrupled lift is tripled.
Which of the following statements is true about maximum L/D ratio? can be found where Cd is minimum located where both Cl and Cd are maximum located where both Cl and Cd are minimum can be found where Cl is at maximum.
It is the angle between the chord line and the longitudinal axis of the aircraft. Dihedral Angle Sweep angle Angle of Incidence Angle of Attack.
The aircraft is said to be trimmed if? The rotation at geometric center is zero The moment at aerodynamic center is zero The rotation at center of gravity is zero The rotation at center of pressure is zero.
What happens to the pressure across the shockwave? none of the above remains the same increase decrease.
It is a flow classification that is between subsonic and supersonic. Transonic Hypersonic High Speed Subsonic Ultrasonic.
It is the sum of indicated airspeed and position as well compressibility errors. Cruising Equivalent Calibrated True.
A type of aerodynamic flow where effects of friction are held negligible.
Compressible Viscous Incompressible Inviscid.
What happens to the pressure of the fluid at isothermal regions? Pressure increases as height increases None of the above Pressure decreases as height increases Pressure remains the same.
It is the design maneuvering speed. VA VB VC VD.
The speed of sound is greatly a function of? Density Temperature Velocity Pressure.
A flow that is both insulated and frictionless. Isochoric Isobaric Isentropic Adiabatic.
It is the science that deals with the interaction of objects in air. Thermodynamics Aerodynamics Dynamics of Rigid Bodies Hydrodynamics.
The following are vector quantities except? Position Velocity Speed Displacement.
Which of the following is not an extensive property? Density Mass Momentum Kinetic Energy.
Which of the following is not an intensive property? Volume Velocity Pressure Temperature.
"P" Factor is most noticeable during high angles of attack and high power settings during takeoff roll. during long flights with an inoperative relief tube None of the above.
What is the relationship of area and velocity in very low velocity airflow? As area increases, velocity of the fluid increases As velocity decreases, the area occupied by the fluid
remains the same As area increases, the velocity remains the same As velocity increases, the area occupied by the fluid
decreases.
Which of the following is not true about equation of state for a perfect gas? Valid for hypersonic flows Usable for gases in which intermolecular forces are
weak Applicable to supersonic flows Relates pressure, temperature, density of a gas.
It is the basis of standard altitude. Geopotential altitude Pressure altitude Absolute altitude Geometric altitude.
The following statements are true about streamlines except? A group of streamlines is called a streamtube All of the above All streamlines are smooth Bernoulli's principle is applicable to streamlines.
What qualifies a flow to be classified as subsonic?
Slower than the speed of light Faster than the speed of light Slower than the speed of sound Faster than the speed of sound.
Which of the following is true about lift generation in an aircraft wing? High pressure is created at the upper surface of the
wing and low pressure at the lower surface Equal pressures are created at the upper and lower
surfaces of the wing Low pressure is created at the upper surface of the
wing and high pressure at the lower surface Low pressure is created at the leading edge of the
wing and high pressure at the trailing edge.
It is an aircraft instrument that measures the total pressure at a point in the flow. Pitot tube Static port Altimeter Velocimeter.
Which of the following is correct about incompressible flows?
Variation of density is not significant Valid for all kinds of subsonic flows Applicable to supersonic vehicles Flow velocity is greater than 100 m/s.
This is the measure of the average kinetic energy of the particles in a gas
Pressure Temperature Specific Volume Density.
Which of the statements is true about Bernoulli principle? None of the Above The concept is only limited to incompressible flows It applies to turbulent flows Mass and energy are conserved.
The following utilize air breathing engines except. Airplanes Hot Air Balloon Rockets Helicopters.
An airplane will stall at the same: Airspeed regardless of the attitude with relation to the horizon Indicated airspeed regardless of altitude, bank angle and load factor Angle of attack regardless of the attitude with relation to the horizon Angle of attack and attitude with relation to the horizon.
With a full flap, the maximum L/D ratio: Increases and the stalling angle increases Decreases and the stalling speed decreases Remains the same and the stalling angle remains the same Remains the same and the stalling angle decreases.
When a leading edge slot is opened, the stalling speed will: Increase Remain the same but will occur at a higher angle of
attack Remain the same but will occur at a lower angle of
attack Decrease.
With flaps lowered, the stalling speed will: Increase Decrease Increase, but occur at a higher angle of attack Remain the same.
Aileron gives: Directional control about the normal axis Lateral control about the longitudinal axis Longitudinal control about the lateral axis Lateral control about the lateral axis.
Under FAR part 23, the Gust velocity at 50,000 ft is? 20 fps 25 fps 15 fps 30 fps.
ATA 28 is? Hydraulic Power Fuel Flight Controls Landing Gears.
ATA 29 is? Hydraulic Power Fuel Flight Controls Landing Gears.
ATA 27 is? Hydraulic Power Fuel Flight Controls Landing Gears.
ATA 32 is? Hydraulic Power Fuel Flight Controls Landing Gears.
One way of reducing radar detection in most military aircraft is? Reducing RCS Using enamel paints Using composite materials Flying at higher altitudes.
Structures capable of carrying only in-pane shearing loads Two-Force Members Shear Panels Membranes Thin-Plates.
Are kinds of designs that incorporate various techniques to mitigate losses due to component failures which includes redundancy and multiple load paths. fail safe design fail proof design safe life reliable design.
In aircraft zoning, zone 400 is? Right wing Left wing Engine Doors.
Which of the following category is not covered by FAR Part 23? Normal Utility Commuter Transport.
The number of joints required to build a statically determinate externally truss with 15 members is _____. 7 8 9 10.
When the number of members of a truss is less than the given relation m = 2j - 3, the truss is called Statically determinate externally truss Statically indeterminate internally truss Frame Linkage.
The following are phases of design exept? specific preliminary detailed conceptual.
The ratio of the torsional moment to the angle of twist is called? Torsional stiffess Shear flow Work Proportionality constant.
These are the limit loads multiplied by a factor of safety Design loads Ultimate loads Design loads and Ultimate loads Margin of safety.
It is the engine whose failure would most adversely affect the performance or handling abilities of an aircraft critical engine ETOPs left engine engine inoperative.
It is also known as symmetric blade effect P-factor C-factor engine inoperative critical mass effect.
It is defined as the shear force per unit edge length of the middle surface. Shearflow Deflection angle Torsional moment Torsional shearing stress.
The most efficient way to create lift on a fixed wing is to use? elliptical wing wing taper wing tip vortex generator.
To counter torque of the helicopter main rotors, the following design can be used except? tail rotor tandem rotor coaxial rotor meshing rotor.
A design having their elevators in ahead of the wings and at the same time contributes to lift lifting canard sweptback design swept front design control canard.
A shock wave angled 90° from the relative flow Oblique Normal Expansion None of the above.
The aspect ratio of a wing is calculated by: Wing area divided by wing span Wing span divided by wing thickness Wing span divided by chord Wing area divided by wing chord.
Lift on the wing is most properly defined as: Force perpendicular to the relative wind Reduced pressure resulting from a laminar flow over the upper camber of an airfoil Force parallel to the relative wind Pressure differential acting perpendicular to the wing.
As the cyclic control is moved forward, the disc tilts forward, the helicopter will? Move backward Move forward Move to the right Move to the left.
It is the mass of helicopter divided by area of rotor blades. Power loading Blade loading Wing loading Disc loading.
Air passes a normal shockwave. Which of the following statement is true? The static temperature increases The velocity increases The static temperature decreases The static pressure decreases.
Airflow passing through an expansion wave? slows down increases the pressure of the air becomes denser decreases the temperature of the air.
What happens to the value of lift as velocity is doubled? Halved Doubled Tripled Quadrupled.
The aircraft is said to be trimmed if? The moment of aerodynamic center is zero The rotation at the center of pressure is zero The rotation at the center of gravity is zero The rotation at the geometric center is zero.
Which of the statements is true about Bernoulli’s principle? Mass and energy is conserved It is limited to incompressible flows It applies to turbulent flows None of the above.
The control surface which gives longitudinal control is: The rudder The aileron The elevators The flaps.
Yawing is a rotation about: The normal axis obtained by elevator The lateral axis obtained by rudder The longitudinal axis obtained by ailerons The normal axis obtained by rudder.
The speed of sound is affected by: Pressure Temperature Density Viscosity.
Spoiler's, when used for roll control will: Reinforce the boundary layer Great turbulence at the wing root Increase the camber at the wing root Decrease lift on the upper wing surface when deployed asymmetrically.
The inputs to an Air speed indicator are from: Static source Pitot pressure A pitot and static source Pitot, Static and density.
When considering air:
1 - Air has mass
2 - Air is not compressible
3 - Air is able to flow of change its shape when subjected to even small pressure
4 - The viscosity of air is very high
5 - Moving air has kinetic energy 1, 2, 3 and 5 2, 3 and 4 1 and 4 1, 3 and 5.
For an aircraft climbing at a constant IAS the Mach number will: Increase Decrease Remain constant Initially show an increase, then decrease.
A wing with a very high aspect ratio (in comparison with a low aspect ratio of wing) will have: Poor control qualities at low airspeeds Increased drag at high angles of attack A low stall speed Reducing bending moment on its attachments points.
Which relationship is correct when comparing drag and airspeed? Parasite drag varies inversely as the square of the
airspeed Induced drag increases as the square of the airspeed Parasite drag increases as the square of the lift
coefficient divided by the aspect ratio Induced drag varies inversely as the square of the
airspeed.
By changing the angle of attack of a wing, the pilot can
control the airplane's: Lift and airspeed, but not drag Lift, gross weight, and drag Lift, airspeed, and drag Lift and drag, but not airspeed.
Typically, a wing is designed to stall from ___ to ___, resulting in more effective aileron control during stall. bottom to top LE to TE root to tip nose to tail.
What climb rate will a single engine aircraft produce at its absolute ceiling? (max weight, clean config, max continuous power) 0fpm 25fpm 27fpm 75fpm.
What causes Ground Effect? Thicker air near the runway Reduced parasite drag Reduced induced drag Increase in available thrust near the runway.
When a change in pressure is accompanied by such a change in density, the flow is called Flow rate Steady flow Incompressible flow Compressible flow.
It expresses the ratio of inertial forces to viscous forces. It also checks whether the flow is laminar or turbulent. Mach Number Ratio of Inertia Reynolds Number Fluid flow Ratio.
A process in which no frictional of other dissipative effects occur. Isentropic Process Adiabatic Process Reversible Process Trust the Process.
One of the main functions of flaps during the approach and landing is to decrease the angle of descent without increasing the airspeed. provide the same amount of lift at a slower airspeed. decrease lift, thus enabling a steeper than normal approach to be made provide a substantial increase in drag to aid in landing.
What force causes an airplane to turn? rudder pressure or force around the vertical axis vertical lift component horizontal component of lift rudder pressure around the lateral axis and elevator force around longitudinal axi.
Recovery from a stall in any airplane becomes more difficult when its center of gravity moves aft center of gravity moves forward elevator trim is adjusted nosedown. rudder travel is improperly adjusted.
What is ground effect? the result of the interference of the surface of the earth with the airflow patterns about an airplane the result of an alteration in airflow patterns increasing induced drag about the wings of an airplane the result of the disruption of the airflow patterns about the wings of an airplane to the point where the wings will no longer support the airplane in flight. the result of the interference of engine’s slipstream to the air around the aircraft.
What causes an airplane (except a T tail) to pitch nose down when power is reduced and controls are not adjusted? the CG shifts forward when thrust and drag are reduced the downwash on the elevators from the propeller slipstream is reduced and elevator effectiveness is reduced when thrust is reduced to less than weight, lift is also reduced and the wings can no longer support the weight the CG shifts aft when thrust and drag are reduced.
Floating caused by the phenomenon of ground effect will be most realized during an approach to land when at less than the length of the wing span above the surface twice the length of the wingspan above the surface a higher than normal angle of attack a lower than normal angle of attack.
In what flight condition must an aircraft be placed in order to spin? partially stalled with one wing low. in a steep diving spiral stalled in power off stall.
What is the effect on total drag of an aircraft if the airspeed decreases in level flight below that speed for maximum L/D? Drag increases because of increased induced drag Drag decreased because of lower induced drag Drag decreases because of increased parasite drag Drag decreases because of lower parasite drag.
The movable rudder usually has an area of _____. 50-60 percent of the horizontal stabilizer 40-45 percent of the total wing area 60-70 percent of total vertical area double of horizontal stabilizer or half of wing area.
This principle supports that the pressure on the surface depends on the angle of deflection and upstream conditions. First Order Theory Second Order Theory First Order Approximation Second Order Approximation.
Define what is a Geopotential Altitude Physical distance between aircraft and reference (e.g. Sea Level) Difference in density with International Standard Atmosphere (ISA) temperature Distance between Center of Earth and parallel surfaces around the spherical earth. Pressure differential with respect to Pressure at Sea
Level.
What limits the high airspeed potential of a helicopter? harmonic resonance Rotor RPM limitations induced drag retreating blade stall.
Which of the following controls the direction of helicopter about the vertical axis? Cyclic Correlator Collective Pedals.
It is the effect by which the force applied only occurs 90
degrees from the point application. rigidity in space Translational lift conservation of momentum Gyroscopic precession.
The lift- and drag forces, acting on a wing cross section Depends on the pressure distribution about the wing cross section. Is normal to each other at just one angle of attack. Is proportional to each other, independent of angle of attack. Varies linearly with the angle of attack.
If your aircraft has wing washout, it is designed to stall
from the? Bottom to top Leading edge to trailing edge Tip to root Root to tip.
When you lower your flaps, you: Decrease wing camber Decrease stall speed Decrease lift Decrease drag.
When you retract your flaps, you immediately decrease: Lift Drag Camber All of the above.
The difference between IAS and TAS will: Increase at decreasing temperature Increase at increasing air density. Decrease at increasing speed. Decrease at decreasing altitude.
Which of the following statements about stall speed is
correct? Decreasing the angle of sweep of the wing will
decrease the stall speed Increasing the angle sweep of the wing will decrease
the stall speed Use of a T-tail will decrease the stall speed Increasing the anhedral of the wing will decrease the
stall speed.
The additional increase in drag at mach no. above the critical Mach no. is due to: Wave drag Increase angle of attack Increased interference drag Increased skin friction drag.
The relative thickness of an aerofoil is expressed in: Camber Meters % camber % chord.
Compared with an oblique shock wave at the same Mach number a normal shock wave has a: Higher expansion Smaller compression Smaller expansion Higher compression.
Increasing the no. of propeller blades will: Decrease the torque in the propeller shaft at max power Increase the max absorption of power Increase the prop efficiency Increase the noise level at max power.
At an airplane's minimum drag speed, the ratio between induced drag and profile drag (Di/Dp) is _____ 1 1/3 1/2 3.
Atmosphere is made of _________ of Argon. 0.94% 0.03% 0.01% 0.004% 20.99% 78.03% 0.0012%.
Atmosphere is made of _________ of Nitrogen. 0.94% 0.03% 0.01% 0.004% 20.99% 78.03% 0.0012%.
Atmosphere is made of _________ of Oxygen. 0.94% 0.03% 0.01% 0.004% 20.99% 78.03% 0.0012%.
Atmosphere is made of _________ of Carbon Dioxide. 0.94% 0.03% 0.01% 0.004% 20.99% 78.03% 0.0012%.
Atmosphere is made of _________ of Hydrogen. 0.94% 0.03% 0.01% 0.004% 20.99% 78.03% 0.0012%.
Atmosphere is made of _________ of Helium. 0.94% 0.03% 0.01% 0.004% 20.99% 78.03% 0.0012%.
Atmosphere is made of _________ of Neon. 0.94% 0.03% 0.01% 0.004% 20.99% 78.03% 0.0012%.
It refers to the varying of wing chord using a uniform airfoil section Airfoil Tapering Planform Tapering Section Tapering Thickness Taperring.
The force perpendicular to the chord of an airfoil is commonly referred as _________. lift force drag force normal force axial force.
To ensure safety during take-off, lift-off velocity should
be _____. 20 percent greater than stalling speed 30 percent greater than stalling speed 15 percent greater than stalling speed equal to the stalling speed.
Ailerons' chord are commonly measured _____. 20 to 33 percent of the wing chord 15 to 30 percent of the wing chord 12 to 15 percent of the wing chord 20 to 25 percent of the wing chord.
In a twin-engine airplane, one mounted on each wing, the torque reaction is neutralized doubled four times less four times greater.
What is the consequence of having too much lateral stability? During crosswind, landing is extremely difficult. During tailwind, landing is extremely difficult. Tendency of sideslip will be eliminated. Increase of airplane's efficiency.
Tangential component of velocity in front of and behind the wave are equal. Tangential component of velocity in front of and behind the wave are equal. Tangential component of velocity in front is greater than the velocity behind the wave. Tangential component of velocity behind is greater than the velocity in front the wave. Normal component of velocity behind is greater than the velocity in front the wave.
On what instance does negative pressure coefficient occurs? When local velocity is higher than freestream
velocity. When the dynamic pressure is twice the pressure
difference. When the freestream velocity is higher than local
velocity. When the local pressure is greater than freestream pressure.
The average force exerted upon a unit area of surface by the bombardment due to random thermal motion of molecules of air or any other fluid is known as _____. dynamic pressure atmospheric pressure static pressure gage pressure.
Too much angle of bank during a level turning flight may cause _____. slipping blanketing skidding porpoising.
It refers to the demonstrated ratio of the change in height during a portion in climb in still air. Lapse Rate Climb Gradient Height Differential Height Slope.
By changing the angle of attack of the wing, the pilot can control the airplane's _____. lift and induced drag lift and drag lift, drag, and airspeed induced drag.
Higher induced angle of attack can be obtained by using _____. lower taper ratio larger wing area higher wing aspect ratio lower wing aspect ratio.
Which of the following best describes the wings with higher aspect ratio? Lower wing-lift curve slope. Steeper wing-lift curve slope. Same wing lift-curve slope with infinite wing. Aspect ratio doesn't affect wing lift-curve slope.
Hazardous vortex turbulence that might be encountered behind large aircraft is created only when the aircraft is _____. producing lift operating at high altitude using high power setting operating at high airspeed.
The angle of attack of a wing directly controls _____. distribution of pressure acting on the wing dynamics acting on the airflow of the wing angle of incidence of the wing amount of airflow below and above the wing.
What flight condition should be expected when an aircraft leaves ground effect? Increase in dynamic stability. Decrease in induced drag and a requirement of lower
angle of attack. Increase in induced drag and a requirement of higher
angle of attack. Decrease in parasite drag permitting a lower angle of
attack.
Which of the following conditions will an aircraft experience the greatest stress? Climbing flight Level flight Turning flight Gliding flight.
The tropopause separates the troposphere from the mesosphere stratopause thermosphere stratosphere.
The upward bending of the main rotor blades of the helicopter caused by the combine forces of lift and centrifugal force ____. Flapping. Feathering. Coning. Coriolis effect.
Rotor blade tendency to accelerate and decelerate as its center of mass moves due to flapping. Flapping. Feathering. Coning. Coriolis effect.
Helicopter fuselages tendency to oscillate as a pendulum longitudinally and/or laterally. Flapping. Gyroscopic Precession Pendular Action Coriolis effect.
Affects rotor efficiency by reducing induced rotor flow Ground Effect Gyroscopic Precession Pendular Action Coriolis effect.
Main rotor act as a gyroscope, and is has precession properties. Ground Effect Gyroscopic Precession Pendular Action Coriolis effect.
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