SU 1 - Airplanes and Aerodynamics Flashcards
Master
3 primary flight controls of an airplane:
- Ailerons
- Elevator (or stabilator)
- Rudder
Control surfaces attached to each wing that move in the opposite direction from one another to control roll about the longitudinal axis.
Ailerons
Primary control device for changing the pitch attitude of an airplane, changing the pitch about the lateral axis. It is usually located on the fixed horizontal stabilizer on the tail of the airplane.
Elevator
one-piece horizontal stabilizer and elevator that pivots from a central hinge point
Stabilator
similar to the horizontal stabilizer but is located in front of the main wings
canard
controls movement of the aircraft about its vertical axis
rudder
Secondary flight controls of an airplane:
wing flaps, leading edge devices, spoilers, and trim systems
attached to the trailing edge of the wing and are used during approach and landing to increase wing lift. This allows an increase in the angle of descent without increasing airspeed
Flaps
high-drag devices deployed from the wings to reduce lift and increase drag. They are found on gliders and some high-speed aircraft.
Spoilers
used to relieve the pilot of the need to maintain constant pressure on the flight controls. They include trim tabs, antiservo tabs, and ground adjustable tabs.
Trim systems
The four aerodynamic forces acting on an airplane during flight are
Lift: the upward-acting force
Weight: the downward-acting force
Thrust: the forward-acting force
Drag: the rearward-acting force
These forces are at equilibrium when the airplane is in:
Lift=Weight, Thrust=Drag
Unaccelerated Flight
“the internal pressure of a fluid (liquid or gas) decreases at points where the speed of the fluid increases.” In other words, high speed flow is associated with low pressure, and low speed flow is associated with high pressure.
Bernoulli’s Principle
the angle between the wing chord line and the direction of the relative wind.
angle of attack
an imaginary straight line from the leading edge to the trailing edge of the wing
wing chord line
direction of airflow relative to the wing when the wing is moving through the air
relative wind
angle of attack at which a wing stalls remains constant regardless of weight, airplane loading, airspeed, etc.
critical angle of attack
results whenever the critical angle of attack is exceeded
stall
forms when the temperature of the collecting surface is at or below the dew point of the adjacent air and the dew point is below freezing.
Frost
Frost on wings disrupts the smooth airflow over the airfoil by causing early airflow separation from the wing. This
Decreases lift
Causes friction and
increases drag
What may make it difficult or impossible for an airplane to take off and should be removed before attempting to take off?
Frost
the result of the interference of the ground (or water) surface with the airflow patterns about an airplane.
Ground effect
The horizontal component of lift makes an airplane…
turn
(left-turning tendency) is greatest at low airspeed, high angles of attack, and high power, e.g., on takeoff.
torque effect
(asymmetric propeller loading) causes the airplane to yaw to the left when at high angles of attack
P-factor
refers to the additional weight carried by the wings due to the airplane’s weight plus the centrifugal force
Load factor
a multiple of the regular weight or, alternatively, a multiple of the force of gravity
Load factor (or G units)
To determine the load acting on an airplane, multiply the load factor by
the airplane’s weight.
have the indicated airspeed on the horizontal axis and the load factor on the vertical axis
Velocity/load factor charts
