Test 1 Questions-Aerodynamics
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.
Which basic flight maneuver increases the load factor on an airplane as compared to straight-and-level flight?
A change in speed during straight flight will not produce any appreciable change in load, but when a change is made in the airplane's flight path, an additional load is imposed upon the airplane structure. This is particularly true if a change in direction is made at high speeds with rapid, forceful control movements. Answer: turns
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
A constant gliding speed should be maintained because variations of gliding speed nullify all attempts at accuracy in judgment of gliding distance and the landing spot.
An airplane said to be inherently stable will
A stable airplane will tend to return to the original condition of flight if disturbed by a force such as turbulent air. This means that a stable airplane is easy to fly.
The wind condition that requires maximum caution when avoiding wake turbulence on landing is a
A tailwind condition can move the vortices of a preceding aircraft forward into the touchdown zone. A light quartering tailwind requires maximum caution. Pilots should be alert to large aircraft upwind from their approach and takeoff flight paths. Answer: light, quartering, tailwind.
As altitude increases, the indicated airspeed at which a given airplane stalls in a particular configuration will
An increase in altitude has no effect on the indicated airspeed at which an airplane stalls at altitudes normally used by general aviation aircraft. This means that the same indicated airspeed should be maintained during the landing approach regardless of the elevation or the density altitude at the airport of landing. Answer: remain the same regardless of altitude.
What force makes an airplane turn?
As the airplane is banked, lift acts horizontally as well as vertically and the airplane is pulled around the turn. Answer: the horizontal component of lift.
Which statement relates to Bernoulli`s principle?
Bernoulli's principle states in part that the 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 with high pressure. Air traveling faster over the curved upper surface of an airfoil causes lower pressure on the top surface. *Air traveling faster over the curved upper surface of an airfoil causes lower pressure on the top surface.
One of the main functions of flaps during approach and landing is to
Flaps increase drag, allowing the pilot to make steeper approaches without increasing 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
Loading in a tail-heavy condition can reduce the airplane's ability to recover from stalls and spins. Tail-heavy loading also produces very light stick forces, making it easy for the pilot to inadvertently overstress the airplane. Answer: difficulty in recovering from a stalled condition
During an approach to a stall, an increased load factor will cause the airplane to
Stall speed increases in proportion to the square root of the load factor. Thus, with a load factor of 4, an aircraft will stall at a speed which is double the normal stall speed. Answer: stall at higher airspeed.
Select the four flight fundamentals involved in maneuvering an aircraft.
Straight-and-level flight, turns, climbs, and descents.
The term 'angle of attack' is defined as the angle
The angle of attack is the acute angle between the relative wind and the chord line of the wing.
When departing behind a heavy aircraft, the pilot should avoid wake turbulence by maneuvering the aircraft
When departing behind a large aircraft, note the large aircraft's rotation point, rotate prior to it, continue to climb above it, and request permission to deviate upwind of the large aircraft's climb path until turning clear of the aircraft's wake. Answer: above and upwind from the heavy aircraft.
When landing behind a large aircraft, the pilot should avoid wake turbulence by staying
When landing behind a large aircraft stay at or above the large aircraft's final approach path. Note its touchdown point and land beyond it. Answer: above the large aircraft's final approach path and landing beyond the large aircraft's touchdown point.
When landing behind a large aircraft, which procedure should be followed for vortex avoidance?
When landing behind a large aircraft, stay at or above the large aircraft's final approach path. Note its touchdown point and land beyond it. Answer: Stay above its final approach flightpath all the way to touchdown.
The angle of attack at which an airplane wing stalls will
When the angle of attack is increased to between 18° and 20° (critical angle of attack) on most airfoils, the airstream can no longer follow the upper curvature of the wing because of the excessive change in direction. The airplane will stall if the critical angle of attack is exceeded. The indicated airspeed at which stall occurs will be determined by weight and load factor, but the stall angle of attack is the same. *remain the same regardless of gross weight
The acute angle A is the angle of
attack
In what flight condition must an aircraft be placed in order to spin?
A spin results when a sufficient degree of rolling or yawing control input is imposed on an airplane in the stalled condition. If the wing is not stalled, a spin cannot occur. Answer: stalled
The amount of excess load that can be imposed on the wing of an airplane depends upon the
At slow speeds, the maximum available lifting force of the wing is only slightly greater than the amount necessary to support the weight of the airplane. However, at high speeds, the capacity of the elevator controls, or a strong gust, may increase the load factor beyond safe limits. Answer: speed of the airplane
In flying the rectangular course, when would the aircraft be turned less than 90°?
Corners 1 and 4.
Ground effect is most likely to result in which problem?
Due to the reduced drag in ground effect, the airplane may seem capable of takeoff well below the recommended speed. It is important that no attempt be made to force the airplane to become airborne with a deficiency of speed. The recommended takeoff speed is necessary to provide adequate initial climb performance. Answer: becoming airborne before reaching recommended takeoff speed.
When are the four forces that act on an airplane in equilibrium?
During unaccelerated flight (steady flight)
What is one purpose of wing flaps?
Flaps increase drag, allowing the pilot to make steeper approaches without increasing airspeed.
Wingtip vortices created by large aircraft tend to
Flight tests have shown that the vortices from large aircraft sink at a rate of about 400 to 500 feet per minute. They tend to level off at a distance about 900 feet below the path of the generating aircraft. Answer: sink below the aircraft generating turbulence.
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
Flight tests have shown that the vortices from large aircraft sink at a rate of about 400 to 500 feet per minute. They tend to level off at a distance about 900 feet below the path of the generating aircraft. Answer: sink into the flightpath of aircraft operating below the aircraft generating the turbulence.
What is ground effect?
Ground effect is the result of the interference of the surface of the Earth with the airflow patterns about an airplane
What is the relationship of lift, drag, thrust, and weight when the airplane is in straight-and-level flight?
Lift and thrust are considered positive forces, while weight and drag are considered negative forces and the sum of the opposing forces is zero. That is, lift = weight and thrust = drag.
Wingtip vortices are created only when an aircraft is
Lift is generated by the creation of a pressure differential over the wing surface. The lowest pressure occurs over the wing surface and the highest pressure occurs under the wing. This pressure differential triggers the roll up of the airflow aft of the wing, resulting in wing-tip vortices. Vortices are generated from the moment an aircraft leaves the ground, since trailing vortices are a by-product of wing lift. Answer: developing lift
Loading an airplane to the most aft CG will cause the airplane to be
Loading in a tail-heavy condition can reduce the airplane's ability to recover from stalls and spins. Tail-heavy loading also produces very light stick forces at all speeds, making it easy for the pilot to inadvertently overstress the airplane. *less stable at all speeds
During a spin to the left, which wing(s) is/are stalled?
One wing is less stalled than the other, but both wings are stalled in a spin.
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?
Referencing FAA Figure 2, use the following steps: 1. Enter the chart at a 30° angle of bank and proceed upward to the curved reference line. From the point of intersection, move to the left side of the chart and read an approximate load factor of 1.2 Gs. 2. Multiply the aircraft weight by the load factor: 3,300 x 1.2 = 3,960 lbs Or, working from the table: 3,300 x 1.154 (load factor) = 3,808 lbs
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?
Referencing FAA Figure 2, use the following steps: 1. Enter the chart at a 45° angle of bank and proceed upward to the curved reference line. From the point of intersection, move to the left side of the chart and read a load factor of 1.5 Gs. 2. Multiply the aircraft weight by the load factor. 4,500 x 1.5 = 6,750 lbs Or, working from the table: 4,500 x 1.414 (load factor) = 6,363 lbs
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?
Referencing FAA Figure 2, use the following steps: 1. Enter the chart at a 60° angle of bank and proceed upward to the curved reference line. From the point of intersection, move to the left side of the chart and read a load factor of 2 Gs. 2. Multiply the aircraft weight by the load factor: 2,300 x 2 = 4,600 lbs Or, working from the table: 2,300 x 2.0 (load factor) = 4,600 lbs
Angle of attack is defined as the angle between the chord line of an airfoil and the
The angle of attack is the angle between the chord line of the airfoil and the direction of the relative wind
Changes in the center of pressure of a wing affect the aircraft`s
The center of pressure of an asymmetrical airfoil moves forward as the angle of attack is increased, and backward as the angle of attack is decreased. This backward and forward movement of the point at which lift acts, affects the aerodynamic balance and the controllability of the aircraft.
What causes an airplane (except a T-tail) to pitch nosedown when power is reduced and controls are not adjusted?
The downwash on the elevators from the propeller slipstream is reduced and elevator effectiveness is reduced
What determines the longitudinal stability of an airplane?
The location of the center of gravity with respect to the center of lift determines to a great extent the longitudinal stability of an airplane. Center of gravity aft of the center of lift will result in an undesirable pitch-up moment during flight. An airplane with the center of gravity forward of the center of lift will pitch down when power is reduced. This will increase the airspeed and the downward force on the elevators. This increased downward force on the elevators will bring the nose up, providing positive stability. The farther forward the CG is, the more stable the airplane.
What is the purpose of the rudder on an airplane?
The purpose of the rudder is to control yaw.
What must a pilot be aware of as a result of ground effect?
The reduction of the wing-tip vortices, due to ground effect, alters the spanwise lift distribution and reduces the induced angle of attack, and induced drag causing floating. Answer: Induced drag decreases; therefore, any excess speed at the point of flare may cause considerable floating.
The greatest vortex strength occurs when the generating aircraft is
The strength of the vortex is governed by the weight, speed, and shape of the wing of the generating aircraft. The greatest vortex strength occurs when the generating aircraft is heavy, clean and slow.
How does the wake turbulence vortex circulate around each wingtip?
The vortex circulation is outward, upward, and around the wing tips when viewed from either ahead or behind the aircraft. Answer: outward, upward, and around each tip.
Floating caused by the phenomenon of ground effect will be most realized during an approach to land when at
When the wing is at a height equal to its span, the reduction in induced drag is only 1.4%. However, when the wing is at a height equal to one-fourth its span, the reduction in induced drag is 23.5% and when the wing is at a height equal to one-tenth its span, the reduction in induced drag is 47.6%. *less than the length of the wingspan above the surface.
The angle between the chord line of an airfoil and the relative wind is known as the angle of
attack
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.
The four forces acting on an airplane in flight are
lift, weight, thrust, and drag
