Airframe Systems & Components Flashcards

What is the primary purpose of the aircraft's primary flight controls?

Answer: To control the aircraft's pitch, roll, and yaw

The primary flight controls of an aircraft are essential for maneuvering it in flight, directly influencing its orientation and trajectory. These controls include the ailerons, which control roll; the elevator, which controls pitch; and the rudder, which controls yaw. By manipulating these surfaces, pilots can change the aircraft's attitude and direction, allowing for controlled ascent, descent, turns, and straight-and-level flight.

Which component is part of the aircraft's secondary flight controls?

Answer: Flaps

Secondary flight controls are devices that augment the primary flight controls and improve the aircraft's performance characteristics, especially during takeoff and landing. Flaps are a common example, extending from the trailing edge of the wing to increase lift and drag at lower airspeeds. This allows the aircraft to take off and land at slower speeds and steeper angles, enhancing safety and operational flexibility.

What material is commonly used in modern aircraft airframes for its strength-to-weight ratio?

Answer: Aluminum alloy

Aluminum alloys are extensively used in modern aircraft airframes due to their excellent strength-to-weight ratio, corrosion resistance, and ductility. These properties allow for the construction of lightweight yet robust aircraft structures, which is crucial for fuel efficiency and performance. While composite materials are increasingly used, aluminum alloys remain a primary material for many structural components due to their proven reliability and cost-effectiveness.

What is the function of a wing spar?

Answer: To provide the primary structural support for the wing

A wing spar is a principal structural member of an aircraft wing, running spanwise from the fuselage to the wingtip. It is designed to carry the primary bending and shear loads experienced by the wing during flight. The spar provides the main strength and rigidity to the wing structure, supporting the skin, ribs, and other components, and is critical for the wing's overall integrity and ability to generate lift.

Which system prevents ice buildup on the leading edges of wings?

Answer: De-icing system

De-icing systems are critical safety features on aircraft, designed to prevent or remove ice accumulation on critical surfaces like the leading edges of wings, tail surfaces, and propellers. Ice buildup can significantly alter the aerodynamic properties of the aircraft, reducing lift and increasing drag, which can be extremely dangerous. These systems typically use heated air, electrical heating elements, or chemical fluids to melt or shed ice, ensuring safe flight operations.

What is the purpose of the aircraft's horizontal stabilizer?

Answer: To stabilize the aircraft's pitch

The horizontal stabilizer is a small wing-like surface located at the tail of an aircraft, primarily responsible for providing longitudinal stability. It helps to control and stabilize the aircraft's pitch, preventing unwanted nose-up or nose-down movements. The elevator, which is a movable part of the horizontal stabilizer, allows the pilot to actively control pitch, making it a crucial component for maintaining stable flight.

Which component transfers cockpit control inputs to the flight surfaces?

Answer: Control linkage system

The control linkage system, often consisting of cables, pushrods, pulleys, and bellcranks, mechanically connects the pilot's controls in the cockpit (yoke/stick, rudder pedals) to the aircraft's primary and secondary flight control surfaces (ailerons, elevator, rudder, flaps). This system translates the pilot's physical inputs into precise movements of the control surfaces, allowing for accurate manipulation of the aircraft's flight path and attitude.

What is a 'monocoque' aircraft structure?

Answer: A structure where the skin supports most of the load

A monocoque aircraft structure is one where the external skin carries the majority of the structural loads, including tension, compression, and shear. Unlike traditional framed structures, it relies on the strength and rigidity of its outer shell to maintain its shape and bear stresses. This design minimizes internal framing, leading to a lighter and more aerodynamically efficient airframe, common in modern aircraft.

Which inspection method is used to detect cracks in airframe structures?

Answer: Dye penetrant inspection

Dye penetrant inspection (DPI) is a widely used non-destructive testing (NDT) method for detecting surface-breaking defects, such as cracks, porosity, and laps, in non-porous materials like aircraft airframes. A liquid penetrant is applied to the surface, allowed to dwell, then removed, and a developer is applied. The developer draws the penetrant out of any surface flaws, making them visible to the inspector, ensuring structural integrity.