1. Aircraft Structures
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Fuselage provides strength, rigidity, and safe enclosure for crew, passengers, and cargo.
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Semi-monocoque fuselage construction uses frames, stringers, bulkheads, and skin for strength.
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Wing structure contains spars, ribs, and stringers to maintain aerodynamic shape.
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Empennage includes horizontal stabilizer, vertical stabilizer, rudder, and elevator.
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Primary flight controls are ailerons, elevator, and rudder for maneuvering.
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Secondary flight controls include flaps, slats, spoilers, and trim tabs.
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Landing gear absorbs landing loads, provides taxi support, and ground clearance.
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Hydraulic actuators extend and retract landing gear during operation.
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Aircraft doors use locking mechanisms to withstand cabin pressurization loads.
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Composite materials reduce weight, improve corrosion resistance, and increase strength.
2. Hydraulic Systems
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Hydraulic system uses pressurized fluid to transmit force and motion.
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Pascal’s law states pressure applied to fluid is transmitted equally.
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Hydraulic reservoirs store fluid, maintain pressure, and remove air bubbles.
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Hydraulic pumps convert mechanical energy into fluid power pressure.
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Filters remove contaminants, dirt, and particles from hydraulic system.
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Hydraulic accumulators store pressure, absorb shocks, and damp pulsations.
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Actuators convert hydraulic pressure into mechanical linear or rotary motion.
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Pressure relief valves prevent over-pressurization and system damage.
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Hydraulic lines are color-coded and labeled for maintenance safety.
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Skydrol hydraulic fluid is fire resistant but corrosive to skin.
3. Pneumatic Systems
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Pneumatic systems use compressed air for brakes, engine starting, and de-icing.
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Sources of pneumatic power include engine bleed air and APU.
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Pressure regulators maintain required pneumatic pressure during operation.
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Moisture separators remove water vapor to avoid icing problems.
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Pneumatic accumulators stabilize system pressure fluctuations effectively.
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Over-pressure relief valves protect pneumatic system against excessive pressure.
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Pneumatic system operates wing anti-ice boots using compressed air.
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Engine cross-bleed valve controls pneumatic supply between engines.
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Pneumatic leak detection uses overheat sensing loops along ducts.
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Pneumatic manifolds distribute bleed air to multiple aircraft systems.
4. Landing Gear Systems
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Retractable landing gear reduces drag and improves aerodynamic performance.
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Nose gear provides steering control during taxiing and take-off.
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Main gear supports aircraft weight during landing and ground operations.
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Oleo strut absorbs landing shocks using hydraulic oil and nitrogen.
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Landing gear doors reduce drag and protect retracted gear.
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Anti-skid system prevents wheel lock-up and reduces tire wear.
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Brake units are multi-disc or carbon disc assemblies for stopping.
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Emergency extension system uses free-fall, pneumatic, or manual methods.
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Proximity sensors provide landing gear position indication to cockpit.
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Tire pressure must be checked regularly for safety and performance.
5. Electrical Systems
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Aircraft electrical system provides power to avionics, lights, and instruments.
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Direct Current (DC) is supplied by batteries and DC generators.
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Alternating Current (AC) is supplied by alternators and inverters.
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Transformer rectifier units convert AC power into regulated DC.
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Circuit breakers protect wiring and components from overcurrent.
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Bus bars distribute electrical power to aircraft subsystems.
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Static inverters convert DC battery power into AC emergency power.
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Ground power unit supplies external electrical power during maintenance.
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Auxiliary Power Unit provides electrical and pneumatic power on ground.
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Emergency power is supplied by battery when generators fail.
6. Avionics Systems
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Pitot-static system measures airspeed, altitude, and vertical speed.
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Altimeter displays aircraft altitude above mean sea level.
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Airspeed indicator uses dynamic and static pressure difference.
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Vertical speed indicator shows climb or descent rate.
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Attitude indicator provides artificial horizon using gyroscopes.
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Heading indicator gives aircraft directional reference during flight.
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Radio altimeter measures height above ground using radio waves.
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Flight Management System integrates navigation, performance, and guidance.
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GPS provides global navigation signals using satellites.
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Autopilot reduces pilot workload by automatically controlling flight path.
7. Fuel Systems
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Fuel tanks store fuel inside wings, fuselage, or stabilizers.
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Boost pumps deliver pressurized fuel to engines and APU.
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Cross-feed valves allow fuel transfer between tanks during flight.
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Fuel control unit meters correct amount of fuel to engine.
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Fuel jettison system allows safe fuel dumping during emergencies.
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Fuel filters remove water, contaminants, and particles from fuel.
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Fuel quantity is measured by capacitance probes inside tanks.
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Vent system prevents vacuum formation inside fuel tanks.
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Fuel heaters prevent ice formation inside fuel lines.
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Gravity feed ensures emergency fuel supply if pumps fail.
8. Environmental Systems
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Pressurization system maintains cabin altitude and passenger comfort.
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Outflow valve regulates cabin pressure by controlling air discharge.
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Safety valve prevents excessive over-pressurization or negative pressure.
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Air conditioning packs provide conditioned air using bleed air.
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Mixing unit blends hot bleed air with cold conditioned air.
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Recirculation fans reduce bleed air demand and save fuel.
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Cabin temperature is controlled automatically or manually by pilots.
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Oxygen system supplies crew and passengers during depressurization.
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Chemical oxygen generators supply passenger masks during emergencies.
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Portable oxygen bottles are available for crew mobility.
9. Fire Protection Systems
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Fire detection uses continuous-loop, spot, and flame detectors.
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Smoke detectors are installed in cargo compartments and lavatories.
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Fire bottles contain Halon extinguishing agent under pressure.
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Squibs rupture fire bottles for agent discharge when activated.
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Engine fire handle closes fuel, hydraulic, and bleed air valves.
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APU fire extinguishing system is independent from engine system.
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Cargo fire suppression system uses multiple Halon bottles sequentially.
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Fire warning indications are displayed on cockpit annunciator panels.
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Built-in test equipment checks fire detection circuits automatically.
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Cabin crew training includes fire drill and extinguisher operation.
10. Ice and Rain Protection
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Pneumatic boots break ice by inflation and deflation cycles.
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Thermal anti-ice uses hot engine bleed air on wings.
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Windshield heat prevents ice formation and removes fogging.
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Pitot probes use electrical heating for anti-ice protection.
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Propeller de-icing uses electrical heating elements on blades.
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Rain removal is achieved by windshield wipers and chemical rain repellent.
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Thermal ice protection prevents engine inlet icing.
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Electrical anti-ice systems protect static ports and sensors.
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Ice detectors provide warning of ice accumulation to crew.
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Integrated system combines pneumatic, thermal, and electrical anti-ice methods.