DGCA CPL Technical General flashcards
DGCA CPL Technical General · Build recall with a focused review session.
32 cards. Read the term and the definition here. The deck at the top of this page is optional.
- Semi-monocoque structure
- Aircraft structure in which the stressed skin carries most shear and tension loads, while stringers resist bending and frames maintain the fuselage shape.
- Fail-safe structure
- A design philosophy in which a component failure is contained by alternate load paths, allowing the aircraft to continue safely until the damaged part is detected and repaired.
- Primary flight controls
- Ailerons control roll, elevators control pitch, and the rudder controls yaw; these are the surfaces essential for manoeuvring the aircraft.
- Wing spar
- The main structural member of a wing that carries bending and shear loads from the wing to the fuselage; ribs attach to it to maintain aerofoil shape.
- Cabin outflow valve
- A valve that regulates the rate of air leaving the pressurised cabin, thereby controlling cabin altitude and differential pressure in response to the pressure controller.
- Differential aileron
- A linkage that deflects the upward-moving aileron more than the downward-moving one, reducing adverse yaw by creating more drag on the rising wing.
- Four-stroke cycle
- The operating cycle of a reciprocating engine with intake, compression, power and exhaust strokes, requiring two crankshaft revolutions to complete one cycle.
- Detonation
- Uncontrolled explosive combustion of the fuel-air mixture after normal spark ignition, causing high cylinder pressure, rising CHT and possible piston damage.
- Pre-ignition
- Ignition of the fuel-air mixture before the spark plug fires, often caused by a hot spot or glowing carbon deposit, leading to power loss and overheating.
- Constant-speed propeller
- A propeller whose blade angle is automatically adjusted by a governor to maintain a selected engine RPM as airspeed and power change.
- Propeller slip
- The difference between the theoretical forward distance a propeller would advance in one revolution and the actual distance travelled through the air.
- Compressor surge
- A violent reversal of airflow through a turbine compressor, often caused by excessive power at low RPM, producing loud bangs, high EGT and possible flameout.
- Pitot-static system
- A system that supplies total pressure from the pitot tube and static pressure from the static port to the airspeed indicator, altimeter, vertical speed indicator and Machmeter.
- Altimeter subscale
- The pressure-setting window on an altimeter; setting QNH makes it read altitude above mean sea level, while QFE makes it read height above a reference point.
- Standard-rate turn
- A turn through 3 degrees per second, completing 180 degrees in one minute; indicated by the turn coordinator at the standard-rate mark.
- Heading indicator
- A gyroscopic instrument that displays aircraft heading; it is not north-seeking and must be periodically aligned with the magnetic compass during straight-and-level flight.
- Radio altimeter
- An instrument that measures absolute height above the terrain by timing reflected radio waves; it is used for low approach and ground proximity warning, not en-route altitude.
- Ohm's law
- The relationship V = I × R, where voltage equals current multiplied by resistance; power can be calculated as P = V × I.
- Parallel circuit
- A circuit in which components are connected across the same voltage; total resistance is less than the smallest branch and reciprocal resistances are summed.
- Aircraft bonding
- The electrical connection of metal structure and components to provide a low-resistance path for static discharge and lightning current, reducing spark and fire risk.
- Magnetos
- Self-contained engine-driven ignition units that generate high voltage for spark plugs independently of the aircraft battery, ensuring ignition if the electrical system fails.
- ARINC 429
- A widely used avionics digital data bus that transmits parameters over a differential pair using 32-bit words with labels identifying the data.
- 2024 aluminium alloy
- A copper-bearing aluminium alloy with high strength and good fatigue resistance, often used for aircraft skins, but it has lower corrosion resistance than 6061.
- Alclad
- Aluminium sheet with a thin pure-aluminium cladding bonded to each surface; the cladding corrodes preferentially and protects the stronger alloy core.
- Galvanic corrosion
- Corrosion caused by electrical contact between dissimilar metals in the presence of an electrolyte, where the more active metal becomes anodic and corrodes.
- Fatigue
- Progressive cracking of a material under repeated cyclic stress, often starting at stress concentrations and growing until the remaining section fails.
- Dye penetrant inspection
- A non-destructive method that applies a coloured penetrant to a cleaned surface, removes excess and uses a developer to reveal surface-breaking cracks.
- Bolt grip length
- The unthreaded portion of a bolt shank; it must match the thickness of the parts so that threads do not bear load in the shear plane.
- Lockwire
- Safety wire installed through drilled fastener heads and twisted so that tension resists loosening; it must be routed so any movement tends to tighten the fastener.
- Airworthiness Directive
- A mandatory instruction issued by the aviation authority to correct an unsafe condition on aircraft; it must be complied with within the stated time or usage limit.
- MEL
- Minimum Equipment List: an approved document that allows dispatch with specified equipment inoperative, subject to conditions and repair intervals, while maintaining an acceptable safety level.
- Eddy current inspection
- A non-destructive test that induces electrical currents in a conductive part and detects changes caused by cracks, corrosion or variations in conductivity and thickness.