JNTU B.Tech III AIRCRAFT SYSTEMS AND CONTROLS Previous Question Paper (February - 2022 - R18)

Aircraft systems must be designed to operate reliably across a wide range of environmental conditions. Key factors include:

• Temperature Extremes: Systems must function from ground-level heat (up to 50°C) to high-altitude cold (down to -55°C). Thermal management is critical to prevent electronic failure and material fatigue.
• Pressure and Altitude: Cabin pressurization and oxygen systems are essential for crew and passenger safety at high altitudes where ambient pressure is low. Systems must also account for rapid pressure changes during climb and descent.
• Atmospheric Conditions: Aircraft encounter moisture, icing, and lightning. Anti-icing and de-icing systems are required for wings and sensors, while shielding is necessary to protect avionics from electromagnetic interference (EMI) during lightning strikes.
• Vibration and Shock: Systems must withstand structural vibrations from engines and aerodynamic loads, as well as high-g shocks during landing or turbulence, requiring robust mounting and component design.
• Contamination and Corrosion: Exposure to salt spray, dust, sand, and hydraulic fluids necessitates the use of corrosion-resistant materials and effective filtration systems.

Aircraft systems are broadly categorized into airframe and avionic systems:

• Airframe Systems: These provide the physical support and operational utility for the aircraft, including:
  • Flight Control Systems: Mechanical or fly-by-wire systems for surface actuation.
  • Landing Gear Systems: Retraction, steering, and braking mechanisms.
  • Environmental Control Systems (ECS): Heating, cooling, and cabin pressurization.
  • Fuel and Hydraulic Systems: Storage, distribution, and power transmission.
  • Emergency Systems: Fire suppression and escape systems.
• Avionic Systems: These encompass the electronic hardware and software for flight management:
  • Communication Systems: Radio and data-link systems for ATC and crew interaction.
  • Navigation Systems: GPS, Inertial Reference Systems (IRS), and ILS for positioning.
  • Flight Management Systems (FMS): Computers for route optimization and performance monitoring.
  • Surveillance and Display Systems: Weather radar, transponders, and cockpit instrumentation (PFD/MFD).