Navigation Aids Flashcards
List the Q Codes:
QDR - Magnetic bearing QDM - Magnetic track QTE - True bearing QUJ - True track QTF - Position established by cross bearings (2 or more DF)
List the VDF accuracy :
A 2° B 5° C 10° D >10° DRDF 1°
How many letters do beacon identifiers havs?
NDB - 2/3
VOR - 3
Waypoint - 5
What is a NDB?
Non Directional Beacon.
En route and approach aid.
Sends a Radio transmission out in all directions that causes the ADF needle in the aircraft to point towards the origin of the signal.
190 and 1750 kHz and maximum range of 50nm
What are the limitations of a NDB?
Static effect - interference from thunderstorm.
Station interference - other radio transmissions may garble readings.
Mountain reflection.
Quadrantal error.
Absence of failure warning.
What is a VOR?
VHF Omni Directional Range
En-route and terminal navigation aid.
Sine signal sent out in full 360°
Compares the phases of a reference and variable signal.
Variable signal is affected by the doppler affect.
Indicates direction to or from VOR.
What are the limitations of a VOR?
Large site required.
Expensive.
Pilot must consider DOC
Range governed by elevation.
What is DOC?
Designated Operational Coverage
What is DME?
Distance Measuring Equipment.
Secondary system that uses transponder signal.
Works with the FMS to cross check and update position information.
What are the limitations of DME?
Only provides distance information.
Innaccurate at close range as measures slant angle.
What is ILS?
Instrument Landing System.
Approach aid that guides aircraft onto the ruway in azimuth (localiser) and elevation (glidepath).
Overlapping beams indicate correct alignment.
What is the accuracy of ILS?
Localiser - 0.5° up to 25nm
Glidepath - 0.14° up to 10nm
List the ILS categories
Cat. RVR. Decisión height Cat 1 - 550m 200ft Cat 2 - 250m 100ft Cat 3a - 200m Nil Cat 3b - 50m. Nil Cat 3c - 0m. Nil
What are the limitations of ILS?
Expensive. Inflexible. Beams must be protected. False localiser. Mirror glidepath.
What types of instrument approach are there?
Precisión/3D - Full ILS
Non-precision/2D - azimuth guidance only.
What is OCA/OCH?
Obstacle Clearance Altitude/Height
The lowest altitude or height above the elevation of the relevant runway threshold or the aerodrome elavation, used in establishing compliance with appropriate obstacle clearance criteria.
Define Minimum Descent Height/Altitude
The height or altitude in a non-precision approach below which Descent may not be made without the required visual reference.
Define Decision Height/Altitude
The height or altitude in a precision approach at which a missed approach must be initiated if the required reference to continue that approach has not been established.
What is MAPt?
Misses Approach Point
The point at or before which the missed approach procedure must be initiated as part of an instrument approach to ensure OCA is not infringed.
What can be used to designate a MAPt?
A point of intersection of a glidepath.
A navigation facility.
A fix.
A specified point from the FAF.
List the instrument approach segments
Arrival - En-route to Initial Approach Fix (IAF)
Initial - IAF to Intermediate Approach Fix (IF)
Intermediate - IF and Final Approach Fix/Point (FAF/FAP)
Final Approach - FAF to landing unless MAPt.
Define a reporting point
Areas with recoded coordinates that can be loaded into RNAV.
Often overlaid with other navigation aid points for use when navaid is out of service.
What is INS?
Inertial Navigation System
Used En-route
On board gyroscopic navigation computer used to track location based on measured changed in velocity from inputted started coordinates.
GIGO
What are the limitations of GPS?
Number of satellite
Military control
Signal degradation - atmospherics, military jamming, space weather.
