Systems Flashcards
What are the Airspeed types and their definitions?
Indicated Airspeed (IAS): Corrected for instrument error
Calibrated Airspeed (CAS): Corrected for Pressure Error (positional error)
Equivalent Airspeed (EAS): Corrected for Compressibility Error
True Airspeed (TAS): Corrected for density error.
What are the ICAO Standard Atmosphere (ISA) level standards.
Temp: 15C
Pressure: 1013.25
Density: 1.225kg/m3
Humidity: Dry Air 0% RH
Speed of Sounds: 661 knots
Which instrument displays vertical speed, what does it display and how does it work?
Vertical speed indicator
Rate of change of altitude
Reads changes in static pressure
What is QNH, QFE, QNE
QNH: Above sea level (ALB will read 400ft)
QFE: Above ground level (Alb will read 0ft)
QNE: Standard pressure setting (1013.25)
Pressure Instrument Names
Airspeed
Altimeter
Vertical Speed Indicator (VSI)
With a constant TAS, what will IAS do as you ascend?
IAS will decrease (2kts/1000ft)
Which instrument displays yaw?
Turn Slip Indicator
What is gyroscopic precession?
If a force is applied to a rotor, the rotor is displaced 90degrees later in the direction of spin
What are the Secular and Annual changes in Earth’s magnetic field?
Secular - Magnetic pole orbits around geographic pole every 960 years in a circle of 17 degrees radius
Annual - Shifts up to 2 degrees east or west every year
What is the ADF System?
It is the Automatic Direction Finder, it is only used for navigation by NDB.
What is a VOR and what frequencies does it operate on?
A Very High Frequency Omnidirectional Radio is a ground-based navaid.
It operates between 108.00-117.95 MHz.
Advantages of VOR over NDB
More accurate
Offers radial instead of bearing
DME pairing
Less susceptible to interference
What is dip angle?
The angle that a magnetic needle makes with the plane of the horizon.
What is magnetic variation?
The difference between true north and magnetic north.
What are Isogonal, agonic and aclinic lines?
Isogonal - Lines that connect two points of the same magnetic variation.
Agonic - Lines of zero variation between magnetic and true north.
Aclinic - Lines that connect points of 0 dip angle (magnetic equator)
What are the Diurnal and Periodic changes to Earth’s magnetic field?
Diurnal (twice yearly): small changes due to declination of the sun
Periodic: eleven year cycle of sun spot activity may cause daily change (not proven)
Not of sufficient magnitude to affect normal navigation.
What are the Primary and Standby Compass’?
Primary - AKA Gyro-Magnetic Compass or Remote Indicating Compass. Utilises a flux valve magnetic sensor, powered by electricity.
Standby - AKA Direct Indicator Compass. Powered by earth’s magnetic field.
Pitotstatic system components
Airflow in (total or pitot pressure) through Pitot tube
Flexible diaphragm which expands depending on total pressure
Static pressure compartment which has a static vent.
Mechanical output
Limitations of Direction Indicating Compass’ (standby compass)
Liquid Swirl (Suspended in liquid which keeps turning)
Scale error
Parralax Error
Alignment error
Deviation (Magnetic interference)
Turning and accelerating errors
Turning & Acceleration error summary.
SAND
South (overshoot turn when)
Accelerating
North (overshoot turn when)
Decelerating
ONUS
Overshoots
North
Undershoots
South
What is Dynamic Pressure?
Pressure created due to motion
Relative to movement (either an object moving through the air or air moving over an object)
What is Static Pressure?
Pressure exerted equally in all directions, result of the weight of all air pressing down
Attitude Indicator has 2 Degrees of Freedom, which makes it a
Tied Gyro
How many DoF does a Rate Gyro have
1
