Ppl – Principles Of Flight Quiz

When the airspeed of an airplane is doubled while in level flight, the parasite drag will become four times greater. This is because parasite drag is directly proportional to the square of the airspeed. So, when the airspeed is doubled, the square of that value becomes four times greater, resulting in four times greater parasite drag.

A standard rate turn is a turn made at a constant rate of 3 degrees per second. To complete a full 360° turn, it would take 120 seconds, which is equivalent to 2 minutes.

An aircraft wing is designed to produce lift by creating a pressure difference between the upper and lower surfaces of the wing. This pressure difference is achieved by having higher air pressure below the wing's surface and lower air pressure above the wing's surface. The curved shape of the wing, called an airfoil, causes the air to move faster over the top surface and slower underneath. According to Bernoulli's principle, the faster-moving air above the wing creates lower pressure, while the slower-moving air below the wing creates higher pressure. This pressure difference generates lift, allowing the aircraft to stay airborne.

The stalling speed of an airplane is most affected by variations in airplane loading. This is because the weight of the airplane directly affects the lift generated by the wings. When the airplane is loaded with more weight, it requires a higher airspeed to generate enough lift to overcome the increased weight and prevent stalling. Conversely, when the airplane is lightly loaded, it requires a lower airspeed to generate sufficient lift. Therefore, variations in airplane loading have a significant impact on the stalling speed of an airplane.

The stalling speed of an airplane is most affected by variations in airplane loading. When an airplane is loaded with more weight, it requires a higher speed to generate enough lift to overcome the increased weight and prevent stalling. On the other hand, when the airplane is lightly loaded, it requires a lower speed to generate enough lift. Therefore, variations in airplane loading directly impact the stalling speed of an airplane. Changes in air density and variations in flight altitude can also affect the stalling speed, but their impact is not as significant as airplane loading.

During the transition from straight-and-level flight to a climb, the angle of attack is increased. This means that the angle between the wing's chord line and the oncoming airflow is increased. As a result, the airflow is redirected, creating a higher pressure difference between the upper and lower surfaces of the wing. This increase in pressure difference leads to an increase in lift, allowing the aircraft to climb. Therefore, the correct answer is that lift is momentarily increased during this transition.

When the airspeed of an airplane is doubled while in level flight, the parasite drag will become four times greater. This is because parasite drag is directly proportional to the square of the airspeed. So, if the airspeed is doubled, the square of the new airspeed will be four times greater than the square of the original airspeed, resulting in four times greater parasite drag.

During the transition from straight-and-level flight to a climb, the angle of attack is increased. This means that the wing is tilted at a higher angle relative to the oncoming airflow. As a result, the airflow over the wing is disrupted, causing an increase in the lift force generated by the wing. Therefore, the correct answer is that lift is momentarily increased during this transition.

In steady-state level flight, the opposing forces acting on an airplane are balanced. This means that the forces of thrust, drag, lift, and weight are all equal. When the forces are equal, the airplane maintains a constant altitude and speed. Therefore, the correct statement is that these forces are equal.

Flaps are used during approach and landing to increase the angle of descent without increasing the airspeed. By extending the flaps, the lift produced by the wings increases, allowing the aircraft to maintain the same airspeed while descending at a steeper angle. This is especially useful in situations where a steeper descent is required, such as when landing on a shorter runway or in adverse weather conditions. By increasing the angle of descent without increasing the airspeed, flaps help pilots control the aircraft's descent profile and improve landing performance.

By changing the angle of attack of a wing, a pilot can control the airplane's lift, airspeed, and drag. The angle of attack refers to the angle between the wing's chord line and the oncoming airflow. By increasing or decreasing the angle of attack, the pilot can increase or decrease the lift generated by the wing. This allows the pilot to control the altitude and climb or descend. Additionally, changing the angle of attack affects the airflow over the wing, which in turn affects the airspeed and drag of the airplane. Increasing the angle of attack can result in a slower airspeed and increased drag, while decreasing the angle of attack can lead to a higher airspeed and reduced drag.

Turns increase the load factor on an airplane compared to straight-and-level flight. When an airplane is turning, the lift generated by the wings needs to counteract not only the weight of the aircraft but also the centrifugal force caused by the turn. This increased load factor puts additional stress on the wings and structure of the airplane. In order to maintain altitude during a turn, the pilot needs to increase the angle of attack and/or increase the airspeed to generate the necessary lift. Therefore, turns increase the load factor on an airplane.

Bernoulli's Principle states that an increase in the speed of a fluid occurs simultaneously with a decrease in pressure. This principle explains why an airplane wing generates lift: the air pressure on the top surface of the wing is lower than on the bottom surface due to the higher velocity of the air over the top, resulting in an upward lift force.

Load factor refers to the ratio between the total airload imposed on the wing and the gross weight of an aircraft in flight. It directly affects the stall speed of an aircraft. Stall speed is the minimum speed at which an aircraft can maintain level flight, and it increases with an increase in load factor. Therefore, load factor and stall speed are directly related.

As altitude increases, the indicated airspeed at which a given airplane stalls in a particular configuration will remain the same regardless of altitude. This is because the indicated airspeed is a measure of the airplane's speed relative to the surrounding air, and does not change with altitude. The stall speed is determined by factors such as the weight and configuration of the airplane, and is not affected by changes in altitude. Therefore, the indicated airspeed at which the airplane stalls will remain constant regardless of altitude.

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. This is because wake turbulence is generated by the wings of an aircraft and it descends behind the aircraft. By staying above the final approach path and landing beyond the touchdown point, the pilot ensures that they do not fly through the descending wake turbulence, reducing the risk of encountering dangerous turbulence that could affect the stability of their own aircraft.

The turn coordinator provides an indicator of the movement of the aircraft about the yaw and roll axes. This means that it shows the aircraft's rotation around the vertical axis (yaw) and the rotation around the longitudinal axis (roll). It does not provide information about the angle of bank, which is the angle between the aircraft's wings and the horizon. It also does not indicate the attitude of the aircraft with reference to the longitudinal axis, which refers to the aircraft's pitch or nose-up/nose-down position.

When landing, wake turbulence from the preceding aircraft can be hazardous. A light, quartering tailwind is the wind condition that requires maximum caution when avoiding wake turbulence. This is because the tailwind can cause the preceding aircraft's wake turbulence to linger on the runway for a longer time, increasing the risk for the following aircraft. Additionally, the quartering tailwind can push the following aircraft into the wake turbulence, making it even more dangerous. Therefore, pilots need to exercise extreme caution and take appropriate measures to avoid the wake turbulence in such wind conditions.

A rectangular wing has a tendency to stall first at the wing root because it has a higher angle of attack at the root compared to the wingtip. This higher angle of attack causes the flow of air over the wing to separate earlier at the root, leading to a stall. As the stall progresses, it moves outward toward the wingtip.

When an airplane turns, it is the horizontal component of lift that is responsible for the change in direction. Lift is the force that opposes the weight of the airplane and it acts perpendicular to the wings. As the airplane banks or tilts to one side, the lift force is divided into two components - the vertical component that opposes gravity and the horizontal component that acts towards the center of the turn. This horizontal component of lift provides the necessary centripetal force to make the airplane turn. Centrifugal force, on the other hand, is a perceived force that appears to push objects outward in a rotating frame of reference, but it is not the force that actually causes the turn.

P-factor is the phenomenon that causes an aircraft to yaw to the left during high angles of attack. This occurs because the descending propeller blade on the right side of the aircraft generates more thrust than the ascending blade on the left side. As a result, there is a greater force on the right side of the aircraft, causing it to yaw to the left. This effect is most pronounced when the aircraft is at high angles of attack, where the relative wind is coming from directly in front of the aircraft. At low angles of attack, the relative wind is more aligned with the aircraft's longitudinal axis, reducing the impact of P-factor. High airspeeds also reduce the effect of P-factor as the airflow becomes more uniform across the propeller.

To increase the rate of turn while decreasing the radius, a pilot should increase the bank and decrease airspeed. Increasing the bank angle allows for a tighter turn, as it increases the horizontal component of lift. By decreasing airspeed, the pilot reduces the centrifugal force acting on the aircraft, allowing for a tighter turn without increasing the radius. This combination of increased bank and decreased airspeed enables the pilot to achieve a faster turn with a smaller turning radius.

The correct answer is "angle of attack regardless of the altitude with relation to the horizon." The angle of attack refers to the angle between the wing's chord line and the oncoming airflow. It determines the lift and drag forces acting on the aircraft. Regardless of the altitude, the angle of attack at which an airplane stalls remains the same. This means that if the angle of attack exceeds the critical value, the airflow over the wings becomes disrupted, causing a loss of lift and a stall. Airspeed and altitude do not directly affect the angle of attack at which a stall occurs.

When an airplane is in ground effect, it experiences an increase in lift due to the reduced downwash caused by the ground. This means that the airplane requires a lower angle of attack to produce the same amount of lift as when it is out of ground effect. A lower angle of attack means that the airplane's wings can maintain a more streamlined position, resulting in improved efficiency and reduced drag. Therefore, a lower angle of attack is needed to produce the same lift in ground effect.

During a turn, the wings of an aircraft generate both vertical and horizontal components of lift. The vertical component of lift counteracts the force of gravity and keeps the aircraft at a certain altitude. However, during a turn, this vertical component of lift decreases due to the change in the direction of the lift vector. To maintain altitude, the pilot needs to increase the back elevator pressure, which increases the angle of attack of the wings and helps generate more lift. This compensates for the loss of the vertical component of lift and ensures that the aircraft maintains its altitude.

During a turn, the vertical component of lift is responsible for counteracting the force of gravity and maintaining altitude. As the aircraft turns, the horizontal component of lift contributes to changing the direction of the aircraft, while the vertical component of lift ensures that the aircraft does not lose altitude. To compensate for the decrease in the vertical component of lift during a turn, the angle of attack must be increased. This increase in angle of attack generates more lift, allowing the aircraft to maintain its altitude.

The correct answer is weight, dynamic pressure, bank angle, or pitch attitude. The angle of attack at which a wing stalls is determined by the aerodynamic characteristics of the wing and is not affected by any of these factors. The stall angle of attack is the same regardless of the weight of the aircraft, the dynamic pressure of the airflow, the bank angle of the aircraft, or the pitch attitude of the aircraft. These factors may affect the aircraft's performance and handling, but they do not change the angle of attack at which the wing stalls.

The force of lift acts perpendicular to the flightpath, while the force of drag acts parallel to the flightpath. The chord line refers to a straight line connecting the leading and trailing edges of the wing, and the longitudinal axis refers to an imaginary line running from the nose to the tail of the aircraft. Therefore, the correct answer is flightpath, as both forces act in relation to the direction of the aircraft's motion through the air.

Stall speed is the speed at which an aircraft can no longer maintain level flight and begins to stall. It is influenced by weight, load factor, and power. Increased weight raises stall speed, while higher load factors (such as during turns) also increase it. Power affects the airflow over the wings, altering stall speed. Properly managing these factors is crucial for safe aircraft operation, particularly during takeoff and landing.

If airspeed is increased during a level turn, the increased airspeed generates more lift. To maintain altitude, the total lift must remain equal to the aircraft's weight. Therefore, the angle of attack must be decreased to reduce lift, or the angle of bank must be increased to increase the component of lift that counteracts the increased airspeed. Both actions will help maintain the necessary lift-to-weight balance and keep the aircraft at the same altitude.

The angle of attack refers to the angle between the wing's chord line and the direction of the oncoming airflow. When the angle of attack becomes too large, the airflow over the wings becomes disrupted, leading to a stall. This is independent of the airplane's attitude with relation to the horizon. The attitude of the airplane refers to its pitch, roll, and yaw, which can affect its stability and maneuverability, but do not directly determine whether a stall will occur. Therefore, the correct answer is that an airplane will stall at the same angle of attack regardless of its attitude with relation to the horizon.

An increase in angle of attack refers to an increase in the angle between the wing's chord line and the oncoming airflow. As the angle of attack increases, the air flowing over the wing is forced to travel a greater distance, resulting in an increase in pressure below the wing. This increase in pressure below the wing leads to an increase in drag. Therefore, the statement "An increase in angle of attack will increase drag" is true.

To maintain altitude during a level turn, if the airspeed is increased, the angle of attack must be decreased or the angle of bank must be increased. Increasing the angle of bank helps to generate more lift, compensating for the increased airspeed, while decreasing the angle of attack reduces the lift generated by the wings, preventing a climb. Therefore, both actions are necessary to maintain altitude.

As airspeed decreases in level flight below that speed for maximum lift/drag ratio, the total drag of an airplane increases because of increased induced drag. Induced drag is the drag that is generated as a result of the production of lift. At lower airspeeds, the angle of attack of the wings needs to be increased to maintain lift, which in turn increases the induced drag. Therefore, the total drag of the airplane increases in this scenario.

When an airplane is in ground effect, it experiences an increase in lift due to the reduction in downwash caused by the ground. This means that the airplane requires a lower angle of attack to produce the same amount of lift as when it is out of ground effect. Therefore, the correct answer is a lower angle of attack.

The angle of attack of a wing refers to the angle between the wing's chord line and the oncoming airflow. It directly affects the distribution of pressures acting on the wing. When the angle of attack increases, the airflow over the wing is disrupted, causing a higher pressure below the wing and a lower pressure above it. This pressure difference generates lift, allowing the wing to generate upward force and support the aircraft. Therefore, the angle of attack plays a crucial role in determining the distribution of pressures acting on the wing.

The correct answer is angle of bank. During a level coordinated turn in smooth air, the airplane wing load depends on the angle of bank. The angle of bank refers to the angle between the airplane's wings and the horizon. Increasing the angle of bank increases the load on the wings, while decreasing the angle of bank decreases the load. The rate of turn and true airspeed may affect the performance of the airplane, but they do not directly determine the wing load in a level coordinated turn.

The performance characteristic of flight at maximum lift/drag ratio in a propeller-driven airplane is range and maximum distance glide. This means that the aircraft can cover the greatest distance while gliding, without the use of engine power. The maximum lift/drag ratio occurs when the lift generated by the wings is at its maximum and the drag is at its minimum, resulting in the most efficient flight. This allows the aircraft to glide for longer distances, maximizing its range.

Accelerating past critical Mach can lead to control difficulties. As an aircraft approaches or exceeds the speed of sound, the airflow over the wings becomes highly compressed, causing a decrease in lift and an increase in drag. This can result in a loss of control authority, making it difficult for the pilot to maneuver the aircraft effectively. Additionally, the increased drag can cause the aircraft to pitch up or experience other unpredictable behaviors, further exacerbating control difficulties. Therefore, accelerating past critical Mach can have adverse effects on the aircraft's controllability.

The correct answer states that there is a corresponding indicated airspeed required for every angle of attack to generate sufficient lift to maintain altitude. This means that as the angle of attack increases or decreases, the indicated airspeed must also be adjusted accordingly in order to maintain the necessary lift to stay in steady, unaccelerated flight. This relationship between angle of attack and indicated airspeed is crucial in understanding the principles of lift and maintaining altitude during flight.

The lift on a wing is most properly defined as the force acting perpendicular to the relative wind. This is because lift is generated by the pressure difference between the upper and lower surfaces of the wing, which is caused by the air flowing over the wing. The relative wind is the direction of airflow relative to the wing, and the force acting perpendicular to it is what creates the upward lift force that opposes gravity. The other options, such as differential pressure and reduced pressure resulting from laminar flow, are not as accurate in defining lift on a wing.

When an airplane leaves ground effect, it means that it is no longer benefiting from the cushioning effect of the air trapped between the wings and the ground. As a result, the airplane will experience an increase in induced drag, which is the drag created by the production of lift. To overcome this increase in drag and maintain the same level of performance, the airplane will require more thrust. Therefore, the correct answer is that the airplane will experience an increase in induced drag and require more thrust.

In a coordinated constant-altitude turn, the load factor imposed on the airplane remains constant. This means that the force experienced by the airplane, which is a multiple of its weight, remains the same throughout the turn. However, the stall speed of the airplane increases in a turn due to the increased angle of attack caused by the bank. As the bank angle increases, the wings generate less lift, which results in an increase in the stall speed. Therefore, the correct answer is that the load factor is constant and the stall speed increases.

When an aircraft is in ground effect, the proximity of the ground creates a cushion of air that reduces the downward flow of air from the wings. This results in an increase in lift because the air pressure underneath the wings is higher, allowing the aircraft to generate more lift. At the same time, the reduced downward flow of air also leads to a decrease in induced drag, which is the drag caused by the creation of lift. Therefore, maintaining the same angle of attack in ground effect will cause an increase in lift and a decrease in induced drag.