Projects:EASA PPL/Aircraft General Knowledge
Mechanical
- Flutter: torsion + bending
- Shimmy: sinusoidal motion/vibration + damper
- Trim tab: reduce/cancel control forces, reduces hinge moment and control surface efficiency
Fuselage & General Design
- Stringers: assist the skin withstand longitudinal compressive loads
- Wing spar: web + girders
- Truss framework: used in light training aircraft
- Monocoque: skin takes all the load
- Semi-Monocoque: skin, frames, stringers -> skin takes majority of the load
- Safe Life Design: may be used for number of cycles or flight hours
Controls
- Yaw pedals: control heading, balance, slip and skip
Propeller
- Constant Speed Propeller:
- Pitch angle increases with increasing true air speed
- manifold pressure increase -> prop pitch angle will increase
- Slipstream effect of Prop: at low airspeed with high power
Electrical
- electrical ice protection: prevent ice on small surfaces
- Static dischargers: on wing and tail tips for electrical discharge + reduce radio interference, limit transfer of electrical charge from clouds
Engine
- Otto motor:
- Diagramm: 2 adiabatic + 2 isochoric lines
- Ignition before top dead center at each second revolution
- Max EGT is associated with mass ratio of 1/15
- Carburettor ice with fixed prop: turn carb heat on, decrease in RPM -> increase in RPM
- Gearbox: magnesium alloy
Magneto
- Magneto impulse coupling: stronger spark at TDC for engine starting, retarded spark
- magnetic field flux: a conductor cuts the flux of a magnetic field -> emf is induced in the conductor
Flaps
- Trailing edge flaps: increase lift at a lower angle of attack
Compass
- true heading -> magnetic heading: map with isogonal lines
- magnetic compass: turning error due to vertival component of earths magnetic field
- compass check swing: measure the angle between magnetic north and compass north
- ANDS: compass indication on accel or decel
Altimeter
- density altitude: the altitude of the standard atmosphere on which the density is equal to the actual density of the atmosphere