Theory of Rotary Wing Flight Practice Test

These questions are part of the practice quiz. Start practicing

• The two basic types of airfoils are:
• Symmetrical airfoils have which characteristic related to stall?
• How does the pilot correct for blowback?
• Counter-torque is achieved by which means?
• Which term is the axis about which the rotor assembly rotates?
• Skin friction on the airfoil is classified as which type of drag?
• What does blowback cause in a rotor system?
• Retreating blade stall is most likely to occur at which speed condition?
• Which law explains why more power is required to accelerate to a target RPM than to maintain it?
• Why is more power required to hover OGE rather than IGE?
• For a nonsymmetrical airfoil, how does the lower camber compare to the upper?
• Which forces in the lift equation can the pilot control?
• Why is center of pressure important?
• What is the upper curvature of the airfoil called?
• How do you counter torque?
• Weathercock Stability is a wind azimuth region associated with Unanticipated Yaw. What is its degree range?
• Which law is involved in the Torque Effect?
• Which edge of the airfoil is rounded?
• What are the three factors in air density (1/2 rho) that will affect lift?
• Are tandem rotor helicopters susceptible to Unanticipated Yaw?
• How is the blade twisted along the span of the rotor blade?
• How is hunting corrected for in an articulated/rigid rotor system?
• What are the two flight conditions?
• In an articulated rotor system, tilting reference is which component?
• Which term denotes the angle between the blade's chord line and the relative wind?
• If the airflow atop the airfoil increases, static pressure will _________ and dynamic pressure will _____________.
• Define rotational relative wind as applied to an airfoil.
• During an autorotation with a turn, which action prevents rotor RPM from exceeding limits?
• Why is hunting necessary in the articulated/rigid rotor system?
• What is the recovery procedure from retreating blade stall?
• Which term describes the lower shape of an airfoil?
• What causes the nose of the helicopter to pitch up and how do you control the pitching up?
• In aerodynamic analysis, which statement best describes the center of pressure's significance?
• Which law is involved in the concept that greater load results in less acceleration?
• In ground effect, up to what altitude is it typically observed?
• If an underspeed trip occurs with rotor RPM, what action should be taken?
• Rotational wind on the rotor disk flows in which direction relative to the forward motion?
• If a spin cannot be stopped, what may be the best course of action?
• Which drag type accounts for drag that does not arise from lift production and includes form and skin friction on non-lifting surfaces?
• What is an airfoil?
• What happens in Main Rotor Disk Vortex Interference?
• Which drag relates to being parallel to and in the same direction as the resultant relative wind?
• Transverse flow effect is noticeable at what airspeed?
• When the rotor disk is tilted, what are the two components of total force?
• Which component acts as thrust when the rotor disk is tilted?
• Which control input counteracts nose-up pitch caused by flap blowback?
• What direction does the main rotor turn?
• Which statement is true regarding drag types in flight?
• List the three simultaneous conditions required for settling with power.
• During rotation and flapping up, what direction is the arrow facing?
• What types of single rotor helicopters are susceptible to UY?
• Describe the symptoms of retreating blade stall in a single rotor helicopter.
• What kind of lower camber does a nonsymmetrical airfoil have?
• The force causing the fuselage to rotate opposite the rotor is:
• List the two components of total aerodynamic force.
• During rotation and airspeed, what direction is the arrow facing?
• Describe the recovery procedure from retreating blade stall.
• What is the first step for recovery from uncommanded yaw?
• In hover, the power required to hover is typically less than out of ground effect.
• What is the minimum descent rate criterion for settling with power?
• Which statement describes blade twist?
• Main Rotor Disk Vortex Interference can cause what effect on the tail rotor?
• Which drag type is primarily associated with rotor-tip vortices?
• Which factor is listed as causing loss or apparent loss of ground effect?
• The blade twist description corresponds to which of the following?
• Which type of drag decreases with an increase in speed?
• During autorotation, which input is primarily used to prevent rotor RPM overspeed?
• Which statement describes effective translational lift?
• Loss of disc area results in what effect?
• Skin friction on the fuselage is what type of drag?
• Define Resultant relative wind.
• Which measurement describes blade span?
• What is the vertical component of total force?
• During rotation only, what direction is the arrow facing?
• As the airflow over the upper surface increases, static pressure and dynamic pressure change how?
• What happens in Tail Rotor Vortex Ring State?
• To prevent uncommanded yaw, what type of wind should we avoid below 30 knots airspeed?
• Which set of actions constitute the three conditions required for dynamic rollover to occur?
• Out of ground effect hover typically requires more power due to what?
• Identify the force that causes the fuselage to rotate in the opposite direction of the main rotor rotation?
• What does weathercock stability refer to?
• What term describes the resistance of a body to a change in its motion?
• What control input is required to recover from dynamic rollover on level ground?
• What type of drag increases with airspeed?
• Which statement best defines an airfoil's purpose?
• What causes relative wind?
• What is Total drag?
• Which term describes the outward force produced when a body moves along a curved path?
• Which law is involved in the statement that more power is needed to obtain a desired RPM than is needed to maintain the RPM?
• What is blade flapping?
• Dissymmetry of lift occurs because the advancing blade has more lift than the retreating blade.
• Non-streamlined fuselage produces what kind of drag?
• The relative wind velocity on the advancing blade equals blade speed plus airspeed.
• During Tail Rotor Vortex Ring State, if yaw rate is allowed to build, into which region can the helicopter rotate?
• What best describes autorotation?
• If the velocity of the relative wind increases, what happens to lift for a given airfoil at a fixed angle of attack?
• Angle of incidence is measured from which line to the rotational relative wind?
• Name the four rotor blade actions.
• A semi-rigid disk tilts relative to the ___
• During translational flight forward, which portion of the disc creates the most lift?
• Center of pressure is defined as the point along the chord line of an airfoil through which all aerodynamic forces are considered to act.
• An articulated disk tilts relative to the ___
• Which term describes the adjustment of blade pitch to redistribute lift during forward flight?
• Which rotor blade action involves changing blade pitch?
• Total drag is defined as the sum of which components?
• Rotor blade coning is a compromise between which two forces?
• Induced Flow defined.
• Which term describes resistance to motion through air, as used in the rotor aerodynamic model?
• Define gyroscopic precession
• Where is lift greatest on a typical rotor blade under the discussed conditions?
• What type of drag is associated with rotor-tip vortices?
• Define autorotation.
• Which of the following is NOT a type of drag considered in rotorcraft analysis?
• Dissymmetry of lift is defined as what?
• Which of the following is a disadvantage of a symmetrical airfoil?
• At what altitude would the aircraft be in ground effect?
• Excessive stress forces on a rotor blade can cause which conditions?
• Which environmental conditions will produce the most lift?
• If the relative wind velocity increases, the airfoil will produce what?
• Define Induced Flow.
• What is the horizontal component of total force?
• Can the angle of attack change with no change in angle of incidence?
• Which of the following is a drag type?
• What is the recommended action to recover from dynamic rollover on level ground?
• Which term describes the upward flexing of rotor blades?
• Which statement is true about a symmetrical airfoil?
• Which altitude marks the boundary of ground effect?
• Which of the following is NOT an advantage of a nonsymmetrical airfoil?
• With an increase in the speed of air over a surface, what happens to dynamic and static pressure?
• What is the relationship of the total force to the rotor tip path plane?
• To produce a precession input 90 degrees ahead, what adjustment is used?
• Which concept explains that a rotor blade pushing air downward experiences an equal and opposite reaction on the blade?
• Define rotor blade coning
• During rotation and flapping down, what direction is the arrow facing?
• What will wind in the Weathercock Stability region cause the aircraft to do?
• At what airspeeds are single rotor helicopters most susceptible to UY?
• What is the straight line from the leading edge to the trailing edge of the airfoil?
• How does the pilot control dissymmetry of lift?
• Which is the tapered edge of the airfoil called?
• A pedal turn to the right requires ______ power than a pedal turn to the left.
• The chord is measured from leading edge to trailing edge of the airfoil. What can be determined from this?
• Which portion of the disc creates the least lift during TFF?
• What does the term tip path plane refer to?
• Dynamic rollover occurs due to a combination of which two factors?
• Settling with power is best described as which of the following?
• Centrifugal force is proportional to which quantity?
• Newton's law of acceleration applies to which condition of flight?
• Which control changes the angle of incidence on all blades simultaneously?
• Which types of UY are mechanical in nature?
• What causes the retreating blade to flap down?
• Which of the following is a component of the Basic Aerodynamic Model?
• Which factor directly leads to the dissymmetry of lift between the advancing and retreating blades?
• Why is the coning angle greatest at the tip of the rotor blade?
• ETL stands for what in rotorcraft terminology?
• Define effective translational lift.
• During downwind turns, are we more or less susceptible to uncommanded yaw?
• With an increase in power, the nose of the helicopter will turn in what direction?
• Describe the relationship between drag and resultant relative wind.
• Which component of the total force acts as lift when the rotor disk is tilted?
• Which of the following is one of the three major categories of Unanticipated Yaw?
• How does excessive coning occur?
• How does the helicopter compensate for dissymmetry of lift?
• Trailing edge term.
• Under the stated conditions, which combination produces the most lift?
• Skin friction on the fuselage is classified as which type of drag?
• Which of the following describes the symptoms of retreating blade stall?
• Which statement about a symmetrical airfoil is true?
• Effective translational lift occurs at an airspeed of
• Describe the relationship of lift to resultant relative wind.
• Which term describes the resultant relative wind in the basic aerodynamic model?
• How is the angle of incidence measured in a rotary-wing aircraft?
• Define rotational relative wind as applied to an airfoil.
• What causes the advancing blade to flap up?
• Precession occurs after how many degrees?
• What is a disadvantage of a nonsymmetrical airfoil in rotor aerodynamics?
• Which term describes the length of the rotor blade from the rotation point to the tip?
• What is the purpose of blade twisting in rotor blades?
• Define settling with power.
• Which term corresponds to the plane traced by the blade tips during rotation?
• Which flight control changes the angle of incidence differentially around the rotor system?
• How is precession overcome?
• Define centrifugal force
• Lift And Total Aerodynamic Force Tilting Rearward On The Airfoil Is What Type Of Drag?
• In Weathercock Stability, when wind acts on the rotorcraft, what is the expected yaw behavior?
• List the required recovery procedures for settling with power.
• Operating at what flight speed is retreating blade stall most likely to occur?
• Newton's Law of Inertia applies to which condition of flight?
• Which factor is listed as contributing to excessive coning?
• In a semi-rigid rotor system, the rotor disk tilts relative to which component?
• Rotor blade coning is a compromise between which two forces?
• Relative wind velocity on the retreating blade equals blade speed minus airspeed.
• Skin friction on the airfoil is what type of drag?
• Resultant relative wind definition.
• Define angle of attack.