Aircraft Systems & Instruments 2025

(a) Which component in an aircraft hydraulic system is used to store fluid under pressure and dampen pressure surges?

1. Reservoir
2. Pump
3. Accumulator
4. Actuator

(b) An Oleo-pneumatic shock strut absorbs the landing impact energy using:

1. A coiled spring
2. Compressed air and oil
3. Rubber discs
4. Magnetic fields

(c) In a Fly-By-Wire (FBW) control system, the pilot's control inputs are transmitted to the actuators via:

1. Steel cables
2. Push-pull rods
3. Electrical signals
4. Hydraulic pipes directly

(d) The principle used by the Artificial Horizon (Attitude Indicator) is:

1. Rigidity in space
2. Precession
3. Bernoulli's Principle
4. Pascal's Law

(e) A "Boot-strap" system is a type of:

1. Hydraulic power pack
2. Air cycle cooling system
3. Engine starting system
4. Anti-skid braking system

(f) The altimeter in an aircraft measures altitude by sensing:

1. Total pressure
2. Static pressure
3. Impact pressure
4. Dynamic pressure

(g) Which instrument indicates the ratio of aircraft speed to the speed of sound?

1. Airspeed Indicator
2. Vertical Speed Indicator
3. Mach Meter
4. Turn and Slip Indicator

(h) The purpose of the "Scavenge Pump" in a dry-sump lubrication system is to:

1. Pump oil to the engine bearings
2. Return oil from the engine to the tank
3. Increase oil pressure for the propeller
4. Cool the oil

(i) Pneumatic de-icing boots usually remove ice by:

1. Heating the leading edge
2. Spraying chemicals
3. Inflating and breaking the ice
4. Vibrating the wing skin

(j) What color is hydraulic fluid typically dyed for identification?

1. Red
2. Blue
3. Green
4. Purple

(a) Draw a schematic diagram of a basic Aircraft Hydraulic System and explain the function of its major components.

(b) Explain the construction and working principle of an Oleo-Pneumatic Landing Gear shock absorber.

(a) Compare Conventional Mechanical Flight Control Systems with Digital Fly-By-Wire Systems. What are the advantages of FBW?

(b) Explain the working principle of an Aircraft Autopilot System. What are the basic axes of control?

(a) Describe the working of a Gas Turbine Engine Fuel System with a neat sketch.

(b) Differentiate between Wet Sump and Dry Sump lubrication systems. Why is Dry Sump preferred in aircraft engines?

(a) Explain the operation of a Boot-Strap Air Cycle Refrigeration System with a schematic diagram.

(b) Discuss the various types of Oxygen Systems used in aircraft.

(a) Describe the construction and working of a Sensitive Altimeter. What are the common errors associated with it?

(b) Explain the working principle of an Air Speed Indicator (ASI). How are Pitot and Static pressures utilized?

(a) Define Gyroscopic Rigidity and Precession. Explain how these principles are applied in the Directional Gyro and Turn Coordinator.

(b) Explain the working of a Drag Cup Tachometer and an Electrical Tachometer.

(a) Explain the working of a typical Pneumatic Power System in an aircraft. How does it differ from a hydraulic system?

(b) Describe the different types of Fire Detection and Extinguishing systems used in aircraft engine compartments.

(a) Differentiate between De-icing and Anti-icing systems. Explain the Thermal Anti-icing system.

(b) Write short notes on: (i) Mach Meter (ii) Accelerometers.