CAA NZ AME Subject 2: Aircraft Engineering Knowledge flashcards
CAA NZ AME Subject 2: Aircraft Engineering Knowledge · 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
- A stressed-skin construction in which the skin carries shear and tension, while stringers, frames, and spar caps stabilize the skin and carry axial and bending loads.
- Fail-safe structure
- A design philosophy where a structure can sustain damage or a crack without catastrophic failure until the damage is found by inspection, allowing repair or replacement.
- Angle of attack
- The angle between the wing chord line and the relative airflow; increasing it increases lift until the critical angle is reached, beyond which the wing stalls.
- Induced drag
- Drag caused by the generation of lift, resulting from wingtip vortices and downwash; it decreases with increasing airspeed and increases with higher load factor and lower aspect ratio.
- Hydraulic accumulator
- A pressure vessel containing a gas charge and hydraulic fluid; it stores energy, damps pressure pulses, and supplies temporary flow during peak system demand.
- Outflow valve
- A valve that regulates the rate of air leaving a pressurized cabin; it controls cabin pressure and cabin altitude by modulating the exhaust flow.
- Detonation
- Uncontrolled explosive combustion of the fuel-air mixture in a reciprocating engine, causing a sharp pressure rise, high temperatures, and possible engine damage.
- Compressor surge
- A reversal of airflow through a gas turbine compressor, often caused by blade stall from excessive angle of attack; it produces loud bangs and loss of thrust.
- Constant-speed propeller
- A propeller whose blade angle is automatically varied by a governor to maintain a selected engine RPM as airspeed and power change.
- Feathering
- Rotating propeller blades to a high-pitch, low-drag position so that a failed engine produces minimum drag and the propeller stops windmilling.
- Transformer-rectifier unit
- An electrical unit that converts alternating current to direct current, typically 115 V AC to 28 V DC, for aircraft DC buses and battery charging.
- Thermal runaway
- A dangerous condition in a nickel-cadmium battery where increased temperature causes increased current, further heating, and possible fire or explosion.
- Pitot-static blockage
- Obstruction of the pitot or static ports that causes erroneous airspeed, altitude, and vertical speed indications; the specific error depends on which port is blocked.
- Attitude and heading reference system
- An avionics system using solid-state gyroscopes and accelerometers to provide attitude and heading data to displays and flight control systems.
- 2024 aluminium alloy
- An aluminium-copper alloy with good fatigue resistance and moderate strength, commonly used for aircraft skins and tension applications; it requires corrosion protection.
- Galvanic corrosion
- Corrosion that occurs when two dissimilar metals are in electrical contact in the presence of an electrolyte; the more anodic metal corrodes preferentially.
- AN bolt
- A standardized aircraft bolt identified by specific head markings; it is used in structural joints and must have the correct grip length and torque.
- Lockwire
- A safety method using twisted wire through fastener heads to prevent loosening; it must be installed in the tightening direction with correct twist and a pigtail.
- Hi-Lok fastener
- A two-part structural fastener consisting of a threaded pin and a collared nut that breaks off at a predetermined torque, providing consistent preload.
- Rivet edge distance
- The distance from the centre of a rivet to the edge of the sheet; it is typically at least twice the rivet diameter to prevent tear-out.
- Exfoliation corrosion
- A layered form of corrosion that attacks grain boundaries in rolled or extruded aluminium, causing the surface to lift and flake like pages of a book.
- Stress corrosion cracking
- Brittle cracking caused by the combined action of tensile stress and a corrosive environment on a susceptible alloy; it can occur with little visible deformation.
- Airworthiness directive
- A mandatory notice issued by an aviation authority requiring inspection, repair, or modification of an aircraft or component to correct an unsafe condition.
- Maintenance release
- A certification signed by an authorised person after maintenance, stating that the work has been completed and the aircraft or component is airworthy.
- Aircraft jacking
- Lifting an aircraft using approved jacks at designated jack points on a level surface, with safety stands placed before any work is done beneath it.
- Aircraft mooring
- Securing an aircraft on the ground with tie-down ropes or chains at designated points, with control locks fitted and covers installed to prevent wind damage.
- Torque wrench
- A calibrated tool used to apply a specified twisting force to a fastener; it must be checked for calibration and used with the correct adapter and procedure.
- Foreign object debris
- Any loose material that can enter an engine, pitot system, or control mechanism and cause damage; prevention requires tool control and inspection of the work area.
- Phugoid oscillation
- A long-period longitudinal oscillation in which an aircraft exchanges kinetic and potential energy while maintaining a nearly constant angle of attack.
- Critical Mach number
- The free-stream Mach number at which airflow over some part of the aircraft first reaches Mach 1, producing shock waves and drag rise.
- Fuel crossfeed
- A system that allows fuel from one tank to feed an engine on the opposite side, used to correct imbalance or manage fuel after a pump failure.
- Exhaust gas temperature
- A turbine engine parameter measured at the exhaust; it indicates turbine temperature and is used to set power and monitor engine health.