Boeing 737: Flight Controls Quiz!

The flap/slat electronics unit (FSEU) provides LE skew detection for slats 2 through 7 except during autoslat operation. This means that it can detect any misalignment or skewing of the leading edge slats. It also provides TE asymmetry protection, which means it can detect any asymmetrical movement of the trailing edge flaps. Additionally, it provides uncommanded motion protection for both the leading edge devices and the trailing edge flaps. Therefore, all of the given statements are correct.

The maximum flap extension altitude refers to the highest altitude at which the flaps on an aircraft can be extended. Flaps are used to increase lift during takeoff and landing, and they are typically retracted once the aircraft reaches a certain altitude. In this case, the correct answer is 20,000 feet, which means that the flaps can be extended up to this altitude before they need to be retracted.

The statement is true because the trailing edge devices on an aircraft typically include double-slotted flaps located both inboard and outboard of each engine. These flaps are used to increase the lift and drag of the aircraft during takeoff and landing, allowing for better control and maneuverability.

During the descent from altitude, the correct position of the SPEED BRAKE LEVER is in the FLIGHT DETENT. This position allows the speed brakes to be deployed and helps in decreasing the airspeed effectively. The FLIGHT DETENT position ensures that the speed brakes are armed and ready for use, providing the necessary aerodynamic drag to slow down the aircraft during descent.

The auto slat system is designed to automatically extend the slats to their full position when the airplane approaches a stall and the trailing edge flaps are set to positions 1 through 5. This helps to increase the lift generated by the wings and improve the aircraft's overall performance and handling characteristics during critical flight conditions.

The elevator feel computer is responsible for providing the feel of the elevator system. It takes inputs such as airspeed and stabilizer position to determine the appropriate elevator position. These inputs are crucial in ensuring that the elevator responds correctly to changes in airspeed and stabilizer position, allowing for a smooth and controlled flight. The other inputs mentioned, such as altitude, elevator position, elevator balance tabs position, and system A hydraulic pressure, may be important for other aspects of the elevator system but are not directly related to the feel of the system.

The correct answer is two because ground spoilers are aerodynamic devices that are deployed on the wings of an aircraft during landing to increase drag and reduce lift. They help in slowing down the aircraft by disrupting the smooth airflow over the wings. Typically, there are two ground spoilers on each wing, making a total of four on the aircraft.

The PTU activates to transfer hydraulic power from system B to system A when a loss of hydraulic pressure in system A is detected, ensuring continued operation of systems like the auto slat system. It does not activate simply due to pump failure or flap switch operation.

The standby rudder Power Control Unit is capable of powering the rudder in addition to hydraulic system A and B. This unit serves as a backup system, ensuring that the rudder can still be operated even if one or both of the hydraulic systems fail.

The correct answer is four because flight spoilers are located on the upper surface of each wing.

The flap load relief system is operational at Flaps 30 and 40. This means that when the flaps are set to either 30 or 40, the system will activate to relieve excessive loads on the flaps. It is not operational at all flap settings or at Flaps 15 only. Therefore, the correct answer is Flaps 30 and 40.

The transfer mechanism in the event of an elevator jam allows the control columns to be physically separated. This means that if one control column becomes jammed or unresponsive, the other control column can still be used to control the elevator. This separation ensures that the pilots can maintain control of the aircraft even in the event of an elevator malfunction.

The correct answer is 4 because the question asks for the number of slats located on each wing. Among the given options, 4 is the only number that represents the number of slats on each wing.

All three statements provided in the question are correct. The primary flight controls are indeed powered by hydraulic systems A and B, with the standby hydraulic system serving as a backup for the rudder and manual reversion being available for the ailerons and elevator. Flight spoilers are used for roll control, descent, and deceleration. Additionally, the trailing edge flaps can be extended and retracted using the alternate flap drive system. Therefore, the answer "All statements are correct" is accurate.

The speed trim operation is activated when the aircraft reaches a speed of 100 knots indicated airspeed (KIAS) or Mach 0.68. This means that once the aircraft reaches this speed, the speed trim system will automatically adjust the aircraft's trim settings to maintain stability and control. The other conditions mentioned, such as the time after takeoff and release of trim switches, as well as N1 above 50%, may be relevant for other aircraft systems or procedures, but they are not directly related to the speed trim operation.

The correct answer is "Excessive differential pressure exists in the elevator feel computer." This means that when there is a significant difference in pressure within the elevator feel computer, the amber FEEL DIFF PRESS light will illuminate. This could indicate a potential issue or malfunction within the system, which requires attention and investigation.

When the air/ground system senses the ground mode (any strut compresses), the flight spoilers will deploy automatically. This means that as soon as any of the landing gear struts are compressed upon landing, the flight spoilers will be activated. The activation of the flight spoilers helps to increase drag and reduce lift, aiding in the deceleration of the aircraft during landing. Therefore, the correct answer is when the air/ground system senses the ground mode (any strut compresses).

The ALTERNATE FLAPS master switch performs multiple functions. It arms the ALTERNATE FLAPS position switch, which allows the flaps to be controlled manually. It also activates the standby hydraulic pump, which provides hydraulic pressure to extend the flaps. Additionally, it closes the Trailing Edge Flaps Bypass valve, ensuring that the hydraulic pressure is directed to the flaps and not bypassed.

The amber LE FLAPS TRANSIT light is inhibited during autoslat operation in flight. Autoslat is a system that automatically extends the leading edge slats on an aircraft to improve lift and control at low speeds. When the autoslat system is active, the LE FLAPS TRANSIT light is turned off to indicate that the slats are not in transit but rather in their extended position. This helps pilots to know the status of the slats during autoslat operation.

Yaw damper inputs can be overridden by either trim or rudder pedal inputs. This means that if the yaw damper switch is ON, the inputs from either the trim or the rudder pedals will have the ability to override the yaw damper system. This allows the pilot to have control over the aircraft's yaw movement, either through adjustments to the trim or by using the rudder pedals to directly input commands.

An alternate retraction system is not provided for the LE devices.

The statement is false because autopilot trim and stabilizer trim do not use separate motors. In fact, they both use the same motor to adjust the trim settings of an aircraft. The autopilot trim system is responsible for automatically adjusting the aircraft's trim based on inputs from the autopilot system, while the stabilizer trim system allows the pilot to manually adjust the trim settings. Both systems work together to ensure the aircraft maintains its desired pitch and stability during flight.

When the standby yaw damper is active, rudder movements are not indicated on the yaw damper indicator. The standby yaw damper is designed to provide stability and control to the aircraft, particularly during yawing motions. It operates independently from the rudder and does not directly indicate rudder movements. Therefore, the statement is false.

The correct indication on the aft overhead panel for the leading edge devices is "All LE devices FULL EXT lights illuminated." This means that all the leading edge devices, including both the LE slats and LE flaps, are fully extended. The other options do not accurately represent the correct indication for the leading edge devices.

When the hydraulic system B pressure is lost, it does not affect the yaw damper switch. The yaw damper switch is a separate system that helps stabilize the aircraft during flight. Even if there is a loss of hydraulic system B pressure, the yaw damper switch will still remain engaged and continue to function properly. Therefore, the statement is true.

With the loss of hydraulic system B, both the main and standby yaw damper functions become inoperative. The main yaw damper functions require hydraulic system A to provide normal pressure and the yaw damper switch to be ON. Similarly, the standby yaw damper functions also require hydraulic system A to provide normal pressure and the yaw damper switch to be ON. However, if the FLT CONTROL B switch is placed to STBY RUD and the YAW DAMPER switch is reset to ON, the standby yaw damper functions can be made available. But in this given scenario, there is no mention of any action being taken to activate the standby yaw damper functions, so the correct answer is that both main and standby yaw damper functions are inoperative.