SIFT Army aviation Exam/70 Accurate
Questions with Answers
What is the Angle of attack (AOA)? - -Angle between chord line and relative
wind
-What is a chord line? - -An imaginary straight line from the leading edge to
the training edge of an airfoil
-What is pitch angle? - -Angle between the longitudinal axis of the aircraft
and the horizon.
-What is an airfoil? - -a streamlined shape designed to produce lift as it
moves through the air (props/wings)
-What is needed in order to create lift? - -Positive angle of attack
-Load Factor - -Ratio of the load supported by the aircraft to the actual
weight of aircraft and its contents. G=L1/L0
-What is L1 in the load factor equation? - -the weight the rotors are carrying
-What is L0 in the load factor equation? - -the weight of the aircraft by itself
-What is the primary cause of lift? - -change in pitch angle and angle of
attack
-What is the angle of incidence? - -the angle between the aircraft's
longitudinal axis and the chord of the wing
-What are the three categories of drag? - -Parasitic Drag
Profile Drag
Induced Drag
-What is parasitic drag? - -Air resistance produced by any part of the aircraft
that does not produce lift.
-What is profile drag? - -Profile drag is incurred from frictional resistance of
the blades passing through the air.
At high airspeeds, profile drag increases rapidly with onset of blade stall or
compressibility.
, -Induced Drag - -Generated by the airflow circulation around the wing as it
creates lift.
-what is maximum lift/drag ratio? - -lift/Drag max
-Basic Empty Weight - -Standard empty weight plus optional equipment
-Licensed empty weight - -The basic empty weight with the engines and
transmission fluid excluded
-maximum gross weight - -maximum allowable weight of the aircraft
-internal max gross weight - -max weight within the interior of the
helicopter including the passengers, pilot, and baggage
-external max gross weight - -max weight that can be supported externally
by the helicopter including external winches
-a front-loaded center of gravity - -Identified by the fuselage tipping
forward, with the nose pointing towards the ground.
-an aft-loaded center of gravity - -Identified by the fuselage tipping
backwards, with the nose pointing up towards the sky.
-what are the four primary controls for a helicopter - -collective, throttle,
cyclic, and anti-torque pedals
-function of the collective - -create lift and control vertical movement
-what does the collective do to create lift - -alters the pitch of the rotor
blades collectively
-which direction on the throttle is decreasing power - -clockwise
-which direction on the throttle is increasing power - -counter clockwise
-what is a correlator? - -It is a mechanical connection between the collective
lever and the engine throttle. When the collective is raised, power is
automatically increased, when lowered, power is decreased. This system
maintains rpm to a desired value, but still requires adjustment of the throttle
for fine tuning.
-what is a governor? - -a sensor that tracks RPM directly and adjusts the
throttle accordingly
Questions with Answers
What is the Angle of attack (AOA)? - -Angle between chord line and relative
wind
-What is a chord line? - -An imaginary straight line from the leading edge to
the training edge of an airfoil
-What is pitch angle? - -Angle between the longitudinal axis of the aircraft
and the horizon.
-What is an airfoil? - -a streamlined shape designed to produce lift as it
moves through the air (props/wings)
-What is needed in order to create lift? - -Positive angle of attack
-Load Factor - -Ratio of the load supported by the aircraft to the actual
weight of aircraft and its contents. G=L1/L0
-What is L1 in the load factor equation? - -the weight the rotors are carrying
-What is L0 in the load factor equation? - -the weight of the aircraft by itself
-What is the primary cause of lift? - -change in pitch angle and angle of
attack
-What is the angle of incidence? - -the angle between the aircraft's
longitudinal axis and the chord of the wing
-What are the three categories of drag? - -Parasitic Drag
Profile Drag
Induced Drag
-What is parasitic drag? - -Air resistance produced by any part of the aircraft
that does not produce lift.
-What is profile drag? - -Profile drag is incurred from frictional resistance of
the blades passing through the air.
At high airspeeds, profile drag increases rapidly with onset of blade stall or
compressibility.
, -Induced Drag - -Generated by the airflow circulation around the wing as it
creates lift.
-what is maximum lift/drag ratio? - -lift/Drag max
-Basic Empty Weight - -Standard empty weight plus optional equipment
-Licensed empty weight - -The basic empty weight with the engines and
transmission fluid excluded
-maximum gross weight - -maximum allowable weight of the aircraft
-internal max gross weight - -max weight within the interior of the
helicopter including the passengers, pilot, and baggage
-external max gross weight - -max weight that can be supported externally
by the helicopter including external winches
-a front-loaded center of gravity - -Identified by the fuselage tipping
forward, with the nose pointing towards the ground.
-an aft-loaded center of gravity - -Identified by the fuselage tipping
backwards, with the nose pointing up towards the sky.
-what are the four primary controls for a helicopter - -collective, throttle,
cyclic, and anti-torque pedals
-function of the collective - -create lift and control vertical movement
-what does the collective do to create lift - -alters the pitch of the rotor
blades collectively
-which direction on the throttle is decreasing power - -clockwise
-which direction on the throttle is increasing power - -counter clockwise
-what is a correlator? - -It is a mechanical connection between the collective
lever and the engine throttle. When the collective is raised, power is
automatically increased, when lowered, power is decreased. This system
maintains rpm to a desired value, but still requires adjustment of the throttle
for fine tuning.
-what is a governor? - -a sensor that tracks RPM directly and adjusts the
throttle accordingly
