Aircraft Structures MCQ Quiz Questions And Answers

Explanation
The correct answer is tension, compression, torsion, shear. These four loads are commonly experienced by an aircraft during flight. Tension refers to the force that pulls the aircraft apart, compression is the force that pushes the aircraft together, torsion is the twisting force experienced by the aircraft, and shear is the force that acts parallel to the surface of the aircraft. These loads are important to consider in aircraft design and structural integrity to ensure safe and efficient operation.

Explanation
Elasticity is the property of a material to regain its original shape after being deformed. This means that when a material is stretched or compressed, it can return to its original size and shape once the external force is removed. Therefore, the statement that a material can return to normal after it has been deformed due to its elasticity is true.

Explanation
Creep is the gradual deformation of a material under a constant load over time. The duration of the load applied is a factor affecting creep because the longer the load is applied, the more time the material has to deform. This is because creep is a time-dependent phenomenon, and the longer the load is sustained, the more the material's internal structure can rearrange itself, leading to increased deformation. Therefore, the duration of the load applied is a significant factor influencing creep.

Explanation
The safe life of an aircraft is dependent on several factors. The number of flying hours elapsed is important because the more hours an aircraft has flown, the more wear and tear it may have experienced. The number of landings is also significant as each landing puts stress on the aircraft's structure and components. The number of pressurization cycles elapsed is crucial as pressurization and depressurization can cause fatigue in the aircraft's structure. Finally, the calendar time is important because even if an aircraft hasn't accumulated a high number of flying hours, the materials and components can still degrade over time.

Explanation
Fail-safe structures do not enable aircraft parts to be produced lighter. In fact, fail-safe structures are designed to ensure that even if a component fails, the overall structure remains intact and operational. This often requires additional reinforcement and redundancy, which can increase the weight of the aircraft parts. Therefore, the statement is false.

Explanation
Fail-safe structure adheres to the concept whereby no single structure supports the entire load. This means that even if one component or structure fails, the overall structure is designed to continue functioning and supporting the load. Fail-safe structures are commonly used in engineering and design to ensure safety and prevent catastrophic failures in various systems and structures.

Explanation
A typical cabin altitude when traveling in a jet transport aircraft is 7,000 to 8,000ft AMSL. This means that the cabin altitude is maintained at a level equivalent to being at an elevation of 7,000 to 8,000 feet above mean sea level. This altitude is lower than the actual altitude at which the aircraft is flying, as it is necessary to maintain a comfortable and safe environment for passengers. By keeping the cabin altitude lower, the aircraft reduces the risk of hypoxia and other altitude-related health issues for passengers and crew.

Explanation
The word "Monocoque" is derived from the Greek and French words, which mean "single shell". This suggests that the correct answer is "Single shell".

Explanation
Longerons were added to a pure monocoque structure to support larger, more powerful aircraft. Longerons are longitudinal structural members that run along the length of the fuselage and provide additional strength and rigidity. They help distribute the loads and stresses generated during flight, ensuring the structural integrity of the aircraft. By incorporating longerons into the monocoque structure, the aircraft becomes capable of handling the increased weight and forces exerted by larger and more powerful engines.

Explanation
Pressurization is essential at an altitude of 10,000ft AMSL. At this altitude, the air pressure is significantly lower than at sea level, and without pressurization, passengers and crew would not receive enough oxygen to breathe comfortably. Pressurization helps to maintain a comfortable and safe cabin environment by regulating the air pressure and oxygen levels inside the aircraft, allowing for normal breathing and preventing altitude-related health issues.

Explanation
Aircraft pressurization causes the aircraft's hull to experience longitudinal and hoop stresses, which result in the lengthening and expansion of the hull, similar to a blown-up balloon. This is due to the increased internal pressure within the aircraft cabin. Therefore, the statement is true.

Explanation
The cargo area in a transport aircraft is normally pressurized. This is because pressurization helps to maintain a suitable environment for the cargo, preventing damage or spoilage during transportation. Additionally, pressurization ensures that the cargo area is safe for any personnel who may need to access it during the flight. Therefore, the statement that the cargo area in a transport aircraft is normally not pressurized is incorrect.

Explanation
Direct vision windows serve as an additional means of escape for the crew in the event of an emergency. These windows are strategically placed in the aircraft to provide a clear line of sight for the crew, allowing them to assess the situation outside and make informed decisions. In case of an emergency, such as a fire or a crash landing, these windows can be opened easily, enabling the crew to evacuate the aircraft quickly and safely. Therefore, the statement "Direct vision windows double as an escape for the crew during an emergency" is true.

Explanation
The main member of an aircraft wing, which the construction is centered around, is called the spar. The spar is a structural component that runs along the length of the wing and provides the main support and strength. It helps to distribute the aerodynamic forces and weight of the aircraft, ensuring the wing remains rigid and stable during flight.

Explanation
A torsion box is a structure made up of two thin layers of material separated by a grid of ribs or spars. This design helps to distribute and resist torsional forces, making the wing more rigid and stable. By using a torsion box in the wing of an aircraft, it ensures that the wing can withstand the forces and stresses experienced during flight, providing the necessary rigidity for safe and efficient operation.