Basic Aerodynamics Flashcards
The four forces acting on an airplane in flight are
-Lift -Weight -Thrust -Drag
(Refer to Figure 1.) The acute angle A is the angle of
Attack
The angle of attack at which an airplane wing stalls will
Remain the same regardless of gross weight
When are the four forces that act on an airplane in equilibrium?
During unaccelerated flight
Wingtip vortices created by large aircraft tend to
Sink below the aircraft generating turbulence
What is ground effect?
The result of the interference of the surface of the Earth with the airflow patterns about an airplane
Which statement relates to Bernoulli`s principle?
Air traveling faster over the curved upper surface of an airfoil causes lower pressure on the top surface
(Refer to figure 62.) In flying the rectangular course, when would the aircraft be turned less than 90°?
Corners 1 and 4
(Refer to figure 66.) While practicing S-turns, a consistently smaller half-circle is made on one side of the road than on the other, and this turn is not completed before crossing the road or reference line. This would most likely occur in turn
4-5-6 because the bank is increased too rapidly during the early part of the turn
When landing behind a large aircraft, the pilot should avoid wake turbulence by staying
Above the large aircraft’s final approach path and landing BEYOND the large aircraft’s touchdown point
What causes an airplane (except a T-tail) to pitch nosedown when power is reduced and controls are not adjusted?
The downwash of the elevators from the propeller slipstream is reduced and elevator effectiveness is reduced
During an approach to a stall, an increased load factor will cause the airplane to
Stall at a higher airspeed
An airplane said to be inherently stable will
Require less effort to control
What is one purpose of wing flaps?
to enable the pilot to make steeper approaches to a landing without increasing the airspeed
Ground effect is most likely to result in which problem?
Becoming airborne before reaching recommended takeoff speed
When executing an emergency approach to land in a single-engine airplane, it is important to maintain a constant glide speed because variations in glide speed
nullify all attempts at accuracy in judgment of gliding distance and landing spot
Changes in the center of pressure of a wing affect the aircraft`s
Aerodynamic balance and controllability
(Refer to Figure 2.) If an airplane weighs 2,300 pounds, what approximate weight would the airplane structure be required to support during a 60° banked turn while maintaining altitude?
4,600 lbs
In what flight condition must an aircraft be placed in order to spin?
Stalled
What is the purpose of the rudder on an airplane?
To control Yaw
How does the wake turbulence vortex circulate around each wingtip?
- Outward
- Upward
- Around each tip
One of the main functions of flaps during approach and landing is to
Increase the angle of descent without increasing the airspeed
An airplane has been loaded in such a manner that the CG is located aft of the aft CG limit. One undesirable flight characteristic a pilot might experience with this airplane would be
Difficulty in recovering from a stalled condition
When landing behind a large aircraft, which procedure should be followed for vortex avoidance?
Stay above its final approach flightpath all the way to touchdown
If an emergency situation requires a downwind landing, pilots should expect a faster
Groundspeed at touchdown, a longer ground roll, and the likelihood of overshooting the desired touchdown point
What force makes an airplane turn?
The horizontal component of lift
Loading an airplane to the most aft CG will cause the airplane to be
Less stable at all speeds
Select the four flight fundamentals involved in maneuvering an aircraft.
- Straight-and-level flight
- Turns
- Takeoff
- Landing
What determines the longitudinal stability of an airplane?
The location of the CG with respect to the center of lift
What must a pilot be aware of as a result of ground effect?
Induced drag decreases; therefore, any excess speed at the point of flare may cause considerable floating
When departing behind a heavy aircraft, the pilot should avoid wake turbulence by maneuvering the aircraft
Above and upwind from the heavy aircraft
What is the relationship of lift, drag, thrust, and weight when the airplane is in straight-and-level flight?
Lift equals weight and thrust equals drag
The angle between the chord line of an airfoil and the relative wind is known as the angle of
Attack
During a spin to the left, which wing(s) is/are stalled?
Both wings are stalled
The wind condition that requires maximum caution when avoiding wake turbulence on landing is a
Light, quartering tailwind
As altitude increases, the indicated airspeed at which a given airplane stalls in a particular configuration will
Remain the same regardless of altitude
When taking off or landing at an airport where heavy aircraft are operating, one should be particularly alert to the hazards of wingtip vortices because this turbulence tends to
Sink into the traffic pattern area surrounding the airport
Which basic flight maneuver increases the load factor on an airplane as compared to straight-and-level flight?
Turns
The amount of excess load that can be imposed on the wing of an airplane depends upon the
Speed of the airplane
(Refer to Figure 2.) If an airplane weighs 3,300 pounds, what approximate weight would the airplane structure be required to support during a 30° banked turn while maintaining altitude?
3,960 lbs
Wingtip vortices are created only when an aircraft is
Develping lift
The term ‘angle of attack’ is defined as the angle
between the wing chord line and the relative wind
Angle of attack is defined as the angle between the chord line of an airfoil and the
direction of the relative wind
The greatest vortex strength occurs when the generating aircraft is
- Heavy
- Clean
- Slow
(Refer to Figure 2.) If an airplane weighs 4,500 pounds, what approximate weight would the airplane structure be required to support during a 45° banked turn while maintaining altitude?
6,750 lbs
Floating caused by the phenomenon of ground effect will be most realized during an approach to land when at
Less than the length of the wingspan above the surface
