Flight Controls Flashcards
FLIGHT CONTROLS
Primary and Secondary Flight Controls
Primary Flight Controls
Ailerons, Elevator, and Rudder
Secondary Flight Controls
Wing flaps, leading edge devices, spoilers, and trim systems
Airfoil Nomenclature
Airfoil
Chord Line
Chord
Mean Camber Line
Maximum Camber
Thickness/Chord Ratio
Leading Edge Radius
a shape capable of producing lift with
relatively high efficiency.
Airfoil
a straight line joining the centers of
curvature of the leading edge and trailing edges of
an airfoil.
Chord Line
the distance between the leading edge and
trailing edge measured along the chord line.
Chord
a line joining the leading edge
and trailing edge of an airfoil, equidistant from the
upper and lower surfaces.
Mean Camber Line
the maximum distance of the
mean camber line from the chord line. Maximum
camber is expressed as a percentage of chord, with
its location as a percentage in tenths of the chord aft
of the leading edge. When the camber line lies above
the chord line, it is said to have a positive camber.
When the camber line is below the chord line, it is
said to have negative camber. A symmetrical airfoil
has no camber because the chord line and camber
line are co-incidental.
Maximum Camber
the maximum thickness
or depth of an airfoil section expressed as a
percentage of chord, with its location as a
percentages of the chord aft of the leading edge. The
thickness and thickness distribution of the airfoil
section have a great influence on its airflow
characteristics.
Thickness/Chord Ratio
the radius of curvature of
the leading edge. The size of the leading-edge radius
can significantly affect the initial airflow
characteristics of the airfoil section.
Leading Edge Radius
also known as relative wind or
free stream flow.
Relative Airflow
Relative airflow has three qualities:
Direction, Condition, Magnitude
air parallel to, and in the opposite
direction to the flight path of the aircraft, in fact the
path of the CG; the direction in which the aircraft is
pointing is irrelevant.
Direction
air close to, but unaffected by the
presence of the aircraft; its pressure, temperature,
and velocity are not affected by the presence of the
aircraft through it.
Condition
the magnitude of the relative airflow is
the true airspeed (TAS).
Magnitude
If airflow does not possess all three qualities, it is
referred to as ___________.
effective airflow
can also be referred
to as aerodynamic incidence. It is the angle formed
between the chord line and the relative airflow. The
angle between the chord line and the effective
airflow is referred to as the effective angle of attack.
Angle of Attack (α or alpha)
the angle between the chord
line and the horizontal datum of the aircraft. (This
angle is fixed for the wing, but may be variable for
the tail plane.)
Angle of Incidence
the aerodynamic force which acts 90 degrees
to the relative airflow.
Lift
the aerodynamic force which acts parallel to
and in the same direction as the relative airflow (or
opposite to the aircraft flight path).
Drag
the resultant of all aerodynamic
forces acting on the airfoil section.
Total Reaction