Army Aviation Section (Sift) Exam
Questions and Answers 100% Pass
Gravity - ✔✔Constantly pulls things downward
Lift - ✔✔Upward force created by difference in air pressure above and below the blade
(how the helicopter flies)
Airfoil - ✔✔blade
Top of the Blade - ✔✔Low pressure
Below Blade - ✔✔High Pressure
Pitch Angle (Angle of Incidence) - ✔✔Angle between chord line and the direction of
rotor's spin
AOA (Angle of Attack) - ✔✔Angle between chord line and direction of incoming air
Chord Line - ✔✔Line drawn between leading edge and trailing edge of airfoil
Positive AoA - ✔✔needed for lift
Weight - ✔✔Force acting on a body due to gravity
Factors that increase effectiveness of lift / increase potency of weight -- Banking -
✔✔vertical lift redirected into horizontal movement. Needs increased airfoil to produce
vertical lift
Load Factor (G-Load) - ✔✔Increases weight on airfoil : G = L1/L0 G-Load Factor
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, L1- Actual Load on Rotor Blades
L0 - Resting Load
Thrust - ✔✔Measured Horizontal Motion - Primarily created by converting lift via
alterations of pitch angle and AOA
Drag - ✔✔Thrust's opposing force -
More thrust - more drag
more velocity - more drag
Three Drag Types ---> - ✔✔Parasitic, Profile, Induced
Parasitic - ✔✔Object and air want to occupt same space - increases with airspeed and is
the dominant type of drag at high airspeeds. Caused by nonlifting parts like fuesalge,
hub, mast
Profile - ✔✔Drag from frictional resistance of spinning airfoils - relatively less powerful
Induced - ✔✔empty Space filled by air above and below the blade (Primary force @ low
speeds)
Total Drag - ✔✔3 subcategories added together
Maximum Lift / Drag Ratio - ✔✔induced drag has decreased significantly and parasitic
drag has not taken over - point at which lift to drag ration is highest and used to
determine a helicopters best rate of climb
Basic Empty Weight - ✔✔Weight of helicopter itself
Maximum Gross Weight - ✔✔Weight helicopter can bear safely (internal, external)
Center of Gravity - ✔✔Point at which entire weight of helicopter (internal + external
attachments) is averaged
© EMILY CHARLENE YEAR 2025-2026, ALL RIGHTS RESERVED 2
Questions and Answers 100% Pass
Gravity - ✔✔Constantly pulls things downward
Lift - ✔✔Upward force created by difference in air pressure above and below the blade
(how the helicopter flies)
Airfoil - ✔✔blade
Top of the Blade - ✔✔Low pressure
Below Blade - ✔✔High Pressure
Pitch Angle (Angle of Incidence) - ✔✔Angle between chord line and the direction of
rotor's spin
AOA (Angle of Attack) - ✔✔Angle between chord line and direction of incoming air
Chord Line - ✔✔Line drawn between leading edge and trailing edge of airfoil
Positive AoA - ✔✔needed for lift
Weight - ✔✔Force acting on a body due to gravity
Factors that increase effectiveness of lift / increase potency of weight -- Banking -
✔✔vertical lift redirected into horizontal movement. Needs increased airfoil to produce
vertical lift
Load Factor (G-Load) - ✔✔Increases weight on airfoil : G = L1/L0 G-Load Factor
© EMILY CHARLENE YEAR 2025-2026, ALL RIGHTS RESERVED 1
, L1- Actual Load on Rotor Blades
L0 - Resting Load
Thrust - ✔✔Measured Horizontal Motion - Primarily created by converting lift via
alterations of pitch angle and AOA
Drag - ✔✔Thrust's opposing force -
More thrust - more drag
more velocity - more drag
Three Drag Types ---> - ✔✔Parasitic, Profile, Induced
Parasitic - ✔✔Object and air want to occupt same space - increases with airspeed and is
the dominant type of drag at high airspeeds. Caused by nonlifting parts like fuesalge,
hub, mast
Profile - ✔✔Drag from frictional resistance of spinning airfoils - relatively less powerful
Induced - ✔✔empty Space filled by air above and below the blade (Primary force @ low
speeds)
Total Drag - ✔✔3 subcategories added together
Maximum Lift / Drag Ratio - ✔✔induced drag has decreased significantly and parasitic
drag has not taken over - point at which lift to drag ration is highest and used to
determine a helicopters best rate of climb
Basic Empty Weight - ✔✔Weight of helicopter itself
Maximum Gross Weight - ✔✔Weight helicopter can bear safely (internal, external)
Center of Gravity - ✔✔Point at which entire weight of helicopter (internal + external
attachments) is averaged
© EMILY CHARLENE YEAR 2025-2026, ALL RIGHTS RESERVED 2
