Nav 02 Flashcards
What errors is a VOR subject to?
Site errors
Poor sighting
Propogation errors
Uneven propogation caused by terrain over long distances
Equipment errors
Incorrect tuning or calibration
Interference errors
Signal interference from other radio sources.
What is a VOR?
A VHF omni-directional radio range. Provides aircraft with a radial from the VOR letting you know where you are in relation to it. It works by transmitting two signals, a reference signal (which is the same in every direction) and a directional signal which varies dependent on the direction you are from the VOR (due to a set of antennas around the VOR which have varying signals programmed), the phase difference between these signals gives you your radial from the VOR. Often co-located with a DME.
Information is displayed on the VOR receiver in the cockpit which indicates the magnetic course to the VOR selected radial or your radial.
Transmits a unique 3 letter identifier via morse code
Signal is FM and VHF.
What is a DME?
Distance measuring equipment. A transponder on the ground that is interrogated by the aircraft transponder before being transmitted back. The time the signal takes to return is used to calculate the slant range of the aircraft from the DME. Gives range in NM. Can be interrogated by up to 100 aircraft at once. Operates UHF. Slant range error can make the reading inaccurate the closer the aircraft is and the higher it is.
Information is displayed on the DME receiver in the cockpit.
What is the accuracy of a VOR?
• Accuracy is plus or minus 1.25º
- 50nms at 1,000ft
- 90nms at 5,000ft
- 150nm at 15,000ft
- 200nms at 25,000ft
Ie LOS means the higher you are the further away you can pick up the signal.
• Spaced between 50nm and 100nms apart to ensure low level coverage.
- Also has the cone of silence as VOR will not work for aircraft directly above it.
What is the accuracy of an DME?
- Accurate to within 1nm
- Can accept up to 100 aircraft interrogations simultaneously
- Subject to slant error - the closer to the beacon, the less accurate the readings become
How are DME’s used?
- Co-located VOR/DME stations provide range and bearing
- Provides positive ranges for aircraft flying same track and interrogating same DME ATC separation
- Co-location with precision approach aid accurate range from touchdown eg ILS
- Enhances the accuracy of holding patterns
- Suitable computer + DME accurate area navigation
- Military use for air to air refueling
How is a VOR radial displayed in the cockpit?
Radio Mangentic Indicator (RMI)
The magnetic bearing of the beacon (QDM) is indicated by an arrow at one end of the VOR pointer.
The radial (QDR) must be shown at the opposite end.
Omni -bearing Selector (OBS)
Shows the QDM deflection from the VOR, ie tells you which way you need to reposition the aircraft to acquire the desired track relative to the VOR but doesn’t show the current a/c heading, provides lateral guidance to achieve desired magnetic track relative to the beacon (independent of heading). Also indicates whether your position from/to the VOR depedent on the selected QDM (eg if you had a QDM of 270 selected when you are on the 270 radial it will show you are from the VOR, ie a QDM of 270 will take you away from the VOR not your heading).
https://www.youtube.com/watch?v=iCCk2ch-xL4
How does an aircraft use a DME?
The aircraft will send out a digital or analogue pulse train on one frequency which is received by the DME, the DME will then send back the same pulse train but on a different frequency back to the aircraft. Two frequencies are used so the aircraft don’t interrogate each other and the pulse train is randomly generated so each aircraft will know when its own signal is being returned.
The time calculated between transmission of the first signal and receipt of the reply is used to work out the range of the DME. This will then be displayed in the cockpit for the pilot.
What is an ADF?
The ADF, or Automatic Direction Finder,
is an older type of a radio navigation instrument.
The needle indicates the relative position (bearing) of the NDB (Non Directional Beacon) to the nose of the aircraft.
Displays the bearing on an RBI
What is a radio bearing?
The angle between the apparent direction of a definite source of emission of radio waves and a reference direction, as determined at DF station
What is Radio Direction Finding?
Direction Finding (DF) or Radio Direction Finding (RDF) is the measurement of the direction from which a received signal was transmitted.
What is QTE?
The true bearing of an aircraft in relation to the Direction Finding Station, ie. the bearing the aircraft is as seen from the DF station.
What is QDR?
The magnetic bearing of an aircraft in relation to the Direction Finding Station, ie. the bearing the aircraft is as seen from the DF station.
What is QDM?
The Magnetic Heading to steer to make for the DF station, aka homing.
What are the methods by which an a/c can calculate its position using DF?
Triangulation
Pilots can establish their approximate position by obtaining two or more bearings from separate DF stations, and plotting the point at which the bearings intercept.
Homing
The procedure of using the DF equipment at your radio station with the radio bearing of an aircraft transmission, whereby the aircraft proceeds continuously towards the station following bearings obtained from your DF equipment.
DF Telecommunication Technique
Requesting the DF information from the DF station. Phraseology
“Station, Full C/s, request QDM/QDR/QTE, Full C/s”
response;
“C/s, Station, QDM/QTE/QDR 270 degrees class Bravo”
these requests can be refused but the reason must be stated.
ADF
The ADF works on the directional properties exhibited by a loop aerial, receiving signals from a ground based transmitter. (It is effectively an airborne DF unit)
Displays a Relative Bearing in relation to the aircraft’s heading using a pointer on an RBI. Whan RBI is added to the A/C heading you will get the QDM to the DF station.
RMI
An arrow is superimposed onto the compass rose so that a QDM can be read straight from the pointer.
The instrument can house more than one arrow to simultaneously display bearing information to more than one beacon.
What errors do NDB’s suffer from?
Static Interference
Heavy precipitation and thunderstorms cause static interference. Often the ADF needle will point directly at the centre of an active TS in preference to the NDB.
Station Interference
Large bearing errors are caused by interference from transmitters operating on similar frequencies to the one being interrogated. Often caused by inaccurate tuning.
Mountain Effect
LF and MF are surface waves and therefore reflected by any high ground in their path. This can result in direct and reflected waves being simultaneously received by the aircraft and causing bearing errors. Normally overcome by flying higher.
Night Effect
Changes in the Ionosphere at night cause interference from transmissions, particularly in the higher medium frequencies, that would normally be out of range. Severe bearing errors are most likely to occur at sunrise and sunset.
Coastal Refraction
Radio waves travel slightly faster over the sea than they do over land. A radio wave crossing the coast at any angle other than 90º is going to be refracted. An aircraft flying over the sea and interrogating an NDB inland is likely to suffer a bearing error
Quadrantal Error
The airframe of an aircraft tends to reflect, refract and re-radiate incoming radio waves so the loop aerial receives a strong signal from the NDB together with a weaker one that has been distorted by the fuselage. Overall, the signal appears to bend towards the fuselage and this error is maximum when it arrives at the aircrafts quadrantal points. Conversely, signals arriving at the aircraft’s cardinal points do not suffer any error.
System Malfunction
Component or systems failure are difficult to detect because there is no failure warning device. Constant monitoring of the equipment is required
What is a True Radio Bearing?
A radio bearing for which the reference is True North
What is a magnetic Radio bearing?
A radio bearing for which the reference direction is Magnetic North.
What is the accuracy of a Class A DF?
+/- 2°
What is the accuracy of a Class B DF?
+/-5°
What is the accuracy of a Class C DF?
+/-10°
What is the accuracy of a Class D DF?
Worse than class C
What is Triangulation?
Pilots can establish their approximate position by obtaining two or more bearings from separate DF stations, and plotting the point at which the bearings intercept.
What is Homing?
The procedure of using the DF equipment at your radio station with the radio bearing of an aircraft transmission, whereby the aircraft proceeds continuously towards the station following bearings obtained from your DF equipment.
What is the DF Telecommunication Technique?
Requesting the DF information from the DF station. Phraseology
“Station, Full C/s, request QDM/QDR/QTE/QUJ, Full C/s”
response;
“C/s, Station, QDM/QTE/QDR/QUJ 270 degrees class Bravo”
these requests can be refused but the reason must be stated.
How would a pilot determine his position using an ADF?
Displays a Relative Bearing in relation to the aircraft’s heading using a pointer on an RBI. Whan RBI is added to the A/C heading you will get the QDM to the DF station.
What is an RMI and how would you use it to navigate using DF?
Basically an ADF onto which arrows are superimposed onto the compass rose so that a QDM can be read straight from the pointer.
The instrument can house more than one arrow to simultaneously display bearing information to more than one beacon.
By adding the aircrafts heading to the Relative bearing to the station displayed on the RMI you can determine your QDM.
What are the advantages of using an NDB for navigation?
- Reception is not limited to line of sight, MF waves propogate around the curvature of the earth
- Maximum range is dependent on the power of the NDB
What are the disadvantages of an NDB?
- The NDB is subject to atmospheric interference, coastal and night refraction, which affects accuracy
- It is not as accurate as a VOR.
What is an ILS?
Instrument Landing System
The Instrument Landing System (ILS) is a highly accurate and dependable means of navigating to the runway in IFR conditions. When using the ILS, the pilot determines aircraft position primarily by reference to instruments. The ILS consists of:
A. The localizer transmitter;
B. The glide path transmitter;
C. The outer marker (or an NDB or other fix); and
D. In association with a suitable runway, the approach lighting system.
Has different categories
The localizer provides lateral guidance. The localizer is a VHF radio transmitter and antenna system using the frequency band as VOR transmitters (between 108MHz and 112MHz). Located at the upwind end of the runway.
The glide path transmitter provides vertical guidance to the pilot during the approach. The ILS glide slope is produced by a ground-based UHF radio transmitter and antenna system, operating in the 329.30 MHz to 335.00 MHz frequency band. Normally 300m from the threshold, also offset by 100-200m.
It is a precision approach.
What is a CAT 1 ILS?
Category I ILS provides guidance information down to a decision height (DH) of not less than 200 ft. Vis not less than 800m or RVR of less than 550m.
The RVR can be reduced to 400m for a non standard CAT I approach.
What are the advantages of an ILS?
Advantages:
Pilot interpreted and simple to use.
‘Precision’ approaches possible, i.e., provides full guidance in azimuth and elevation, in some cases during the landing ‘roll out’.
Can be coupled to auto-pilot for automatic approach and landings.
Warns of any failures so does not require constant monitoring.
What are the disadvantages of an ILS?
Disadvantages:
Subject to interference from commercial VHF radio stations.
Reflections from other ground facilities can create ‘false’ glide paths.
Shortage of frequencies.
Where would an ILS localiser be located?
At the upwind end of the runway, normally 300m from the opposite threshold
Where is an ILS glidepath located?
Normally situated around 300m from the landing threshold and offset between 100-200m from the centreline.
Where is the outer marker of an ILS located?
3-6nms from threshold
Flases a blue light in the cockpit 400Hz
Where would the middle marker of an ILS be located?
900-1200m
Flases a blue light in the cockpit 400Hz
What does the DME element of an ILS do?
It provides the slant range between the aircraft and the runway threshold (irrespective of where the DME itself is located).
Provides range information instead of the marker beacons
The DME channel will be automatically paired to the localiser frequency.
What is the accuracy of the DME element of an ILS?
Accurate only within localizer coverage and up to 25,000ft
How does the localizer component of an ILS work?
The localizer provides lateral guidance. The localizer is a VHF radio transmitter and antenna system using the frequency band as VOR transmitters (between 108MHz and 112MHz). Two separate frequencies are broadcast from two lobes, where the signals are received in equal measure is the centreline of the runway, receiving either more strongly than the other means that a course correction is required.
Located at the upwind end of the runway.
How does the glidepath component of the ILS work?
The glide path transmitter provides vertical guidance to the pilot during the approach. The ILS glide slope is produced by a ground-based UHF radio transmitter and antenna system, operating in the 329.30 MHz to 335.00 MHz frequency band. Normally 300m from the threshold, also offset by 100-200m.
What is the overlap for the localizer lobes and what frequency do they operate on?
5°
90Hz and 150Hz
What is the frequency band for the localiser?
between 108MHz and 112MHz VHF
What is the frequency band of the Glide path?
329.30 MHz to 335.00 UHF
What is the overlap for the Glidepath lobes and what frequencies do they use?
1° to a maximum range of 10nm
90Hz and 150Hz
What is the localizers coverage area?
Centreline +/-10° out to 25nm
Centreline +/-35° out to 17nm
What is the normal ILS glidepath angle?
3°
What is the DME’s protected range?
Extends 8° either side of the centreline and vertically from 0.45x GP to 1.75x GP
Up to a distance of 10nm.
Why are ILS localizers and glidepaths frequency paired?
- Reduces cockpit workload
- Guards against mismatching
- Only the localizer frequency needs to be published and selected.
What are the rates of height loss for the approach angle?
2.5°= 250ft per nm
3°= 300ft per nm
3.5°= 350ft per nm
Do ILS’s need to be monitored by engineers?
No as they monitor themselves using automatic equipment that monitors the radiation fields.
If the power drops below an acceptable level, or anything abnormal happens the ILS automatically ceases to transmit navigation info.
How are ILS’s identified?
Using a three letter Morse designator.
How can ILS information be displayed in the cockpit?
On an HSI (Horizontal Situation Indicator) or OBS (Omni-directional Bearing Selector)
What do the dots on an OBS signify?
Each horizontal Dot indicates 0.5° of variation from centreline
Each vertical Dot indicates 0.15° deviation from the glidepath.
What is a CAT II ILS?
Category II
ILS approaches and a DH lower than 200ft but not less than 100 ft. RVR not less than 350m.
You can have non standard CAT II approaches that are missing some or all of the elements of a standard CAT II precision approach but still use these figures above.
What is a CAT III A ILS?
Category III
A- Decision height lower than 100ft or no decision height, RVR of no less than 200m.
What are the figures for a CAT III B ILS?
B- Decision height lower than 50ft or no decision height
RVR not less than 200m but not less than 75m.
What are the figures for a CAT III C ILS?
C-A precision instrument approach and landing with no decision height, and no runway visual range limitations.
What are the three components of an ILS?
Localizer
Glidepath
DME
What is INS?
Intertial Navigation System
A series of gyrscopes and accelorometers that can deduce the a/c’s current position by measuring its movements from the reference point entered at the start of the flight. It is standalone system.
It cannot be restarted once in flight.
RNS (Reference Navigation System) is an INS that updates using data derived from other nav aids.
What is a GPS?
Global Navigation Satellite Systems
Uses satellites in orbit to determine position by taking the time the signal was sent from each satellite and when it was received to work out where it is in relation to 3 or more satellites, giving the aircrafts position with reference to the centre of the earth.
What errors do GPS receivers suffer from?
Ionosphere and Troposphere Delays The satellite signal slows as it passes through the atmosphere. The system uses a built-in average, not exact, amount of delay.
Orbital errors
Also known as “ephemeris errors” these are inaccuracies of the satellites’ reported location.
Satellite/Geometery Shading
Ideal satellite geometry exists when the satellites are located at wide angles relative to each other. Poor geometry results when the satellites are located in a line or in a tight grouping.
Receiver Clock Errors
Since it is not practical to have an atomic clock in your GPS receiver, the built-in clock can have very slight timing errors.
Number of Satellites Visible
Due to operating line of sight causing position errors, or possibly no position reading at all. GPS units will not work indoors, underwater, or underground.
Signal Multi-Path
Occurs when the GPS signal is reflected off objects such as tall buildings or large rock surfaces before it reaches the receiver. This increases the travel time of the signal, thereby causing errors.
These errors can be corrected by SBAS, ABAS, or GBAS
Whats is ABAS?
Aircraft Based Augumentation System
Augments and/or integrates the information obtained from the GNSS elements with other information available on board the aircraft (eg. INS)
The aim is to enhance the overall performance of the GPS equipment on board in terms of integrity (continuity) availability, and (accuracy)
What is GBAS
Ground Based Augmentation System
Local Area Augmentation System is the ICAO definition ground based augmentation for Satellite Navigation, uses ground based Nav aids and sensors to correct GPS errors. For example a DGPS (Differential GPS) is a ground based station that knows its exact location and can use that information to correct the error.
GBAS is the European application of LAAS (Local Area Augmentation System).
What is SBAS?
SBAS is a generic term for GNSS augmentations, which use geostationary satellites to broadcast information to users over a large geographical area.
European EGNOS (European Geostationary Navigation Overlay Service)
Similar to DGPS, but uses two satellites to further correct readings together with ground stations
Define a Precision Approach
An instrument approach and landing using precision lateral and vertical guidance with minima as determined by the category of operation.
Note. Lateral and vertical guidance refers to the guidance provided either by:
a) a ground-based navigation aid; or
b) computer generated navigation data displayed to the pilot of an aircraft.
c) a controller interpreting the display on a radar screen (Precision Approach Radar (PAR)
Define a non-precision approach
An instrument approach and landing which utilises lateral guidance but does not utilise vertical guidance.
Non-precision approaches which are pilot interpreted make use of ground beacons and aircraft equipment such as VOR, NDB and the LLZ element of an ILS system, often in combination with DME for range.
What does MaPt mean on an approach chart?
Missed Approach Point
What does FAF mean on an Approach Chart?
Final Approach Fix,
NPA’s Only
What does FAP mean on an Approach Chart?
Final Approach Point
PA’s only
What does IAF mean on an approach chart?
Initial Approach Fix
What does IF mean on an approach chart?
Intermediate Fix
What is a STAR?
Standard Instrument Arrival Route
A set of standard published procedures that take an a/c from the en-route phase of flight to Approach phase. It normally ends at the IAF.
On an approach plate, what type of procedures can be used if a straight in approach is not possible?
Where no suitable IAF or IF is avaliable to construct a straight in approach,
- a REVERSAL procedure;
- RACETRACK procedure;
- Or HOLDING pattern is required
What are the stages of an Approach?
- Arrival
- Initial (starts at IAF)
- Intermediate (starts at intermediate fix IF)
- Final (starts at FAP or FAF)
- Missed approach (starts at MAPt)
What are missed Approach Points?
A missed approach point may be:
1) Glide Path / Decision Alt(Hgt)
2) NAV FACILITY
3) FIX
4) Specified distance from FAF
- Missed approach kept simple
- Each IAP has a published missed approach procedure
- If the required visual reference is not established at the MAPt, INITIATE A MISSED APPROACH at once
- One MAPt for each IAP
- If missed approach initiated prior to the MAPt, comply with the MA Procedure to remain sector safe.
What is a DH or DA?
Decision Height/Altitude
The height/Alt on a PA where the pilot must decide whether he wishes to continue the landing attempt or initiate a Missed Approach Procedure (MAP) on a Precision Approach
What are the different Approach Category Speeds?
CAT. A nominal Vat less than 91 kts IAS
CAT. B nominal Vat 91 kts to 120 kts IAS
CAT. C nominal Vat 121 kts to 140 kts IAS
CAT. D nominal Vat 141 kts to 165 kts IAS
CAT. E nominal Vat 166 kts to 210 kts IAS
What level of Precision Approach are GNSS systems capable of?
Down to CAT I approach limits.
What is RAIM?
Receiver Autonomous Integrity Monitoring
A technique of ABAS Receiver Autonomous Integrity Monitoring (RAIM) The GNSS receiver/processor determines the integrity of the GNSS signals without reference to sensors or integrity systems other than the receiver itself.
This determination is achieved by a consistency check among redundant pseudo-range measurements.
What is AAIM?
Airborne Autonomous Integrity Monitoring (AAIM),
Type of ABAS where GNSS information is complemented with onboard sensors and other components.
What is DGPS?
Differential GPS
Where a ground reference station is used to determine the errors in a satellite signal and broadcasts out the corrections. Making the GNSS signals more accurate.
What types of IAP are Non Precision Approaches?
- VOR
- NDB
- SRA
- ILS (localizer only)
- GNSS
- VDF
What types of IAPs are precision approaches?
- ILS
- PAR (Precision Approach Radar)
- RNP Approach
- MLS (Microwave Landing System)
What is a precision approach terrain chart used for?
Planning of the approach only.
For what type of aircraft are IAPs?
IFR
If there is no IAF or IF suitable to construct a straight in approach what must an IAP have?
Either a;
- Reversal Procedure
- Racetrack Procedure
- or a holding pattern.
What is a base turn?
A reversal procedure for an IAP
What is a procedure turn?
A reversal procedure that allows an IAP where it is not a straight in approach.
What does the pilot normally do during the intermediate approach segment?
- Adjust speed and configuration for final approach
- Keep the descent gradient nice and shallow
- Obstacle clearance reduces from 1000ft to 500ft
What does FAF mean on an approach chart?
The final approach fix (for a non precision approach)
What does the pilot normally do during the final approach segment?
- Align and descend the aircraft for landing
- May conduct a visual manoeuvre for the runway.
Where does the final approach segment end?
When the missed approach point is reached.
What can define a MAPt?
- Glide path DA or DH
- Nav facility
- Fix
- Specified distance from FAF (this will be another DME jobby)
What is a MDA or MDH?
Minimum Descent Altitude/Height
The point below which a pilot must decide whether to perform a missed approach procedure on a non-precision approach.
What is VM(C)?
Visual Manoeuvring (Circling)
Is the term used to describe the visual phase of flight, after completing an Instrument Approach.
What is RNAV?
Area Navigation
A method of navigation which permits aircraft operation on any desired flight path within the coverage of station-referenced navigation aids or within the limits of the capability of self contained nav aids, or a combination of both.
Basically allows you to fly using waypoints instead of having to fly point to point with nav aids.
How does RNAV work?
Uses waypoints referenced to Nav aids or self contained nav aids on the aircraft.
Provides LNAV (Lateral-RNAV) and VNAV (Vertical RNAV) to ensure accuracy with the WGS84 system.
What is B-RNAV?
Basic RNAV
Requires aircraft to track keep within +/-5nm for at least 95% of the flight time.
Only for en-route
All IFR aircraft must be B-RNAV compliant.
What are RNP’s?
Required Navigation Performance
“a statement of the navigation performance necessary for operation within a defined airspace”
Basically the required accuracy of your PBN that is necessary on a route or RNP area.
What happens if a system cannot maintain the required navigational performance?
It must be monitoring itself and if it fails to meet the specification it must provide an alert.
On what are RNP’s based?
INS perviously but GNSS is used these days.
What are the five RNP accuracies?
1
4
10
12.6
20
NM
Are the five standard RNP accuracies sufficient for approaches?
No, they are only for en-route.
What are RNP routes?
Fixed and published ATS routes which can be flight planned for use by aircraft that comply with the RNP requirements.
What are RNP areas?
An area/ volume of airspace of defined dimensions where RNP requirements can be specified by the authority.
In these areas unpublished tracks (random tracks) may be flight planned and flown.
What is P-RNAV?
Precision RNAV
RNAV with an accuracy requirement of +/-1nm
Allows for en-route and TMA ops, can also be applied to SIDS and STARS
Aircraft that comply with this may operate on these SIDs and STARs
What is RNP-RNAV?
No requirement for airborne monitoring of RNP acurracy achieved as accuracy is ensured operationally.
Allows for an accuracy of +/-0.3nm
This can be used in terminal areas.
What is RNP APCH?
RNP approaches
These require an accuracy of +/-1.0nm for the initial, intermediate and missed approach phases and +/-0.3nm for the final approach.
What is RNP (AR) APCH?
RNP (Authorisation Required) Approach
Defined as an RNP approach procedure that requires a lateral TSE (total systems error) lower than the standard RNP values on any segment of the approach procedure down to 0.1nm and similar to ILS Cat 2/3.
What are the three components of PBN?
- The navigation application
- Navigation Specification
- Navigation Infrastructure.
With regards to RNAV what is TSE?
Total system error.
The difference between the true position and desired position of the aircraft.
With regards to RNAV what is PDE?
Path Definition Error
The difference between the true position and estimated position.
With regards to RNAV what is NSE?
Navigation System Error.
The difference between the true position and estimated posiion. This is sometimes known as PEE (position estimated error)
With regards to RNAV what is FTE?
Flight Technical Error
The accuracy with which the a/c is controlled as measured by the indicated a/c position with respect to the indicated command or desired position.
With regards to RNAV what is VNAV?
Vertical Navigation
Provision for guidance for vertical navigation
With regards to RNAV what is LNAV?
Lateral Navigation
Provision of area nav guidance in the horizontal plane.
With regards to RNAV what is FRT?
Fixed radius turn
A turn at a waypoint in the en-route phase of flight using a FRT of either 22.5nm for FL200 and above or 15nm below FL200
With regards to RNAV what is a waypoint?
A specified geographical location used to define an area nav route or the flight path of an A/c using area nav.
With regards to RNAV what is Parallel Offset?
A desired track parallel to & left or right of the parent track specified in nautical miles of offset distance.
With regards to RNAV what is a fly-by waypoint?
A waypoint which an aircraft flies-by by anticipating the turn necessary for the next one.
With regards to RNAV what is a fly-over waypoint?
A waypoint which must be flown over. The turn to the next waypoint will therefore need a correction turn first.
How can STARs be terminated?
Two types of termination
Closed- uninterrupted STAR right down to the final approach segment of the relevant instrument approach.
Open- ends at a waypoint abeam the final approach segment, aircraft will continue to fly the published heading from this point, so will require radar vectors or visual manoeuvre to the final approach track.
How long does it take GPS satellites to orbit Earth?
12 hours
Who funds the Galileo system?
ESA and EU
What is EGNOS?
European Geostationary Navigation Overlay Service
Uses two satellites to correct the readings from those providing the actual positioning.
A type of SBAS.
What is the benefit of GPS and Galileo?
You can use both together and they are free
When can signal multi-path occur?
In built up areas
Give an example of a stand alone system
INS
What do we mean by stand alone?
That the system can navigate without reference to any external information.
What does PBN identify?
It identifies a set of navigation specifications that provide a set of performance guarantees from the aircraft.
Is there any requirement for an RNP RNAV system to be monitored when airborne?
No
Does RNP need to be airborne monitored?
Yes
How many types of ILS approach are there?
7
5 Standard ones and the 2 special ones
What minimum range must an ILS localizer have?
17nm
Where is the ILS reference point?
Above the intersection of the centreline and the threshold.
What does an NDB provide?
A bearing
What is a locater beacon?
NDB with an L
A local NDB at an airfield
What does LNAV and VNAV use?
WGS 84
What types of bearings can you get from VDF?
QTE
QDR
QDM
QUJ
What frequency band does an ADF operate on?
MF
Same as the NDB
What frequency band does an NDB work on?
LF (not in the UK) & MF
190 to 1750KHz
What is an NDB’s radius of coverage?
10-500nm
