EAWS - Enlisted Aviation Warfare Specialist Aircraft Fundamentals and Systems Questions and Answers — Questions and Answers
Question 1: An aircraft's landing gear fails to retract after takeoff. The hydraulic pressure gauge indicates a rapid drop to zero, and a visual inspection from the cabin reveals fluid streaming from the right main gear wheel well. Which of the following components has most likely failed?
- An actuating cylinder seal (Correct answer)
- The main system reservoir
- A pressure relief valve
- An engine-driven pump
Correct answer: An actuating cylinder seal
The scenario describes a localized leak associated with a specific component's operation (landing gear). An actuating cylinder is the component that converts hydraulic pressure into the mechanical motion to move the gear. A failure of its seal would result in a significant fluid leak at that location when the system is pressurized, leading to a loss of system pressure as described. A reservoir failure would likely not be localized to the wheel well, a pump failure would cause pressure loss without a massive external leak, and a relief valve failure would typically vent fluid overboard at the valve's location, not necessarily in the wheel well.
Question 2: Most modern naval aircraft fuselages use a semi-monocoque construction. What is the primary characteristic of this design?
- The external skin is the sole load-bearing component.
- A framework of steel tubes provides the primary structural strength.
- The skin is reinforced by a substructure of formers and stringers that share the structural load. (Correct answer)
- All structural loads are carried by a single, central keel beam.
Correct answer: The skin is reinforced by a substructure of formers and stringers that share the structural load.
Semi-monocoque construction is a widely used method where the aircraft's skin is attached to a substructure of bulkheads, formers, and stringers. This design allows the skin and the substructure to share the stresses, providing a strong yet relatively lightweight structure. In contrast, a pure monocoque design relies solely on the skin, and a truss structure uses a rigid framework of tubes.
Question 3: Within a turbofan engine, what is the primary function of the compressor section?
- To ignite the fuel-air mixture.
- To drive the fan and other engine accessories.
- To decrease the velocity of the exhaust gases to reduce noise.
- To squeeze incoming air and increase its pressure and temperature before combustion. (Correct answer)
Correct answer: To squeeze incoming air and increase its pressure and temperature before combustion.
The compressor section, located behind the fan, is composed of rotating blades and stationary stators that draw in air and compress it. This process significantly increases the pressure and temperature of the air, making it more volatile for efficient combustion when mixed with fuel in the combustion chamber.
Question 4: Which of the following correctly describes the typical roles of AC and DC power on a naval aircraft?
- AC is used exclusively for avionics, while DC powers all motors and pumps.
- DC power is the primary power source, converted to AC only for specific high-power systems.
- AC power is used for high-power systems like motors and heating, while DC power is used for solid-state electronics and as a backup source from batteries. (Correct answer)
- AC and DC power are used interchangeably, with the aircraft's systems able to accept either type of current.
Correct answer: AC power is used for high-power systems like motors and heating, while DC power is used for solid-state electronics and as a backup source from batteries.
Aircraft electrical systems typically use AC as the primary generated power for heavy-load items like motors, pumps, and lighting. This AC power is then converted to DC through Transformer-Rectifier Units (TRUs). DC power is ideal for sensitive electronic components, avionics, and for charging the aircraft's batteries, which serve as an essential emergency power source.
Question 5: Movement of an aircraft around its longitudinal axis, also known as roll, is controlled by which primary flight control surface?
- Elevators
- Rudder
- Ailerons (Correct answer)
- Flaps
Correct answer: Ailerons
The longitudinal axis runs from the nose to the tail of the aircraft. Movement around this axis is called roll. Ailerons, located on the outboard trailing edge of the wings, move in opposite directions to create a differential in lift, causing the aircraft to roll left or right.
Question 6: A pilot is conducting a pre-flight check and cycles the flight controls. When they push the control stick forward, a specific control surface moves. What is the primary purpose of this action during flight?
- To yaw the aircraft's nose to the right.
- To increase the rate of climb.
- To decrease the aircraft's pitch and cause the nose to lower. (Correct answer)
- To increase wing lift for takeoff.
Correct answer: To decrease the aircraft's pitch and cause the nose to lower.
Pushing the control stick forward actuates the elevators, which are located on the horizontal stabilizer. This movement causes the elevators to deflect downwards, which in turn pushes the aircraft's tail up and the nose down. This action controls the aircraft's movement around the lateral (pitch) axis.
EAWS - Enlisted Aviation Warfare Specialist Aircraft Fundamentals and Systems Questions and Answers
An aircraft's landing gear fails to retract after takeoff.
The hydraulic pressure gauge indicates a rapid drop to zero, and a visual inspection from the cabin reveals fluid streaming from the right main gear wheel well.
Which of the following components has most likely failed?