11.5.7 Avionics- Nav Systems Flashcards
What is true north?
True North is where bearings are related to the Earth’s True North.
What is magnetic north?
Magnetic North is where bearings are related to the Earth’s Magnetic North.
What is compass north?
Compass North is where bearings are related to the aeroplanes Compass.
What is distance?
Distance is provided by the DME system in Nautical Miles.
What is provides a height indication?
Height is provided by the RAD ALT system in Feet.
What is slant range?
Is Distance down to the DME STN (Hypotenuse).
What is a mile in metres?
Mile is a Statute value of 1609 Metres.
What is a nautical mile?
It is one minute of arc measured at the Equator. 1 Nautical Mile = 1852 Metres.
What is Heading? (HDG)
The direction in which the nose of the aircraft is pointing. It is measured in degrees (000-360°) clockwise from true, magnetic, or compass north.
What is Track? (TK)
The direction in which an aircraft is moving over the surface of the Earth; is also measured in degrees from true or magnetic north. Only true TK is plotted. If there were no wind, there would be no drift and TK would be the same as HDG; also the case with a direct head- or tail-wind.
What is desired track? (DSR TK)
The planned direction over the Earth in which it is intended the aircraft shall move.
What is track error? (TKE)
The angular displacement between the actual Track and Desired Track. It is always measured from DSR TK to TK.
What is cross track error? (XTK)
The physical displacement, in nautical miles, of the aircraft to the left or right of the desired track.
What is drift angle? (DA)
Drift is the angle between HDG and TK due to the effect of a cross-wind. The direction of drift is always measured from HDG to TK.
How do you know which way the drift angle is going?
If TK is less than HDG, drift is to the left, and if TK is greater than HDG it is to the right
What is true airspeed?
The actual speed of the aircraft through the air. It will differ significantly from the airspeed indicated on the Airspeed Indicator (ASI) due to the air becoming less dense the higher the aircraft flies.
What is ADF?
Automatic direction finding.
What frequency does ADF work on?
190 kHz to 1750 kHz
What is relative bearing?
Defined as the bearing angle between the aircraft’s nose and the ground station.
What two types of antenna must an ADF system have to provide bearing information?
Omni-directional sense
Directional loop
What colour are ADF pointers on the EFIS?
Cyan
What does Azimuth?
Azimuth is the angle in a horizontal plane between true north and the direction of the radio navigation device.
What is QDM?
Magnetic bearing to the station from the aircraft.
What is QDR?
Magnetic bearing from the station to the aircraft.
What is QUJ?
True bearing to the station from the aircraft
What is QTE?
True bearing from the station to the aircraft.
When was VOR developed and deployed?
1937 and 1946
Where are VOR stations commonly placed?
At airports
What is a VORTAC?
Site that shares VOR and TACAN (military version) from the same site.
What types of VOR are there?
CVOR
BVOR
DVOR
TVOR
VOT
VORTAC
What are the two most common types of VOR?
CVOR and DVOR
What is CVOR?
Conventional VOR
What is DVOR?
Doppler VOR for eliminating error
What is CDI?
Course Deviation Indicator
What is the benefit of the HSI?
it combines the CDI and heading.
What frequency does VOR operate at?
108MHz to 117.95 MHz
What channel spacing does VOR have?
50 KHz
What frequencies are the ILS bands allocated too?
Odd tenths of each 0.5MHz i.e. 109.10
How many channels does ILS and VOR have respectively?
160 VOR
40 ILS
Out of 160 Channels how many are allocated to En-route VOR (Category A) and how many to Terminal VOR (TVOR) (Category B).
A 120
B 40
What is a radio magnetic instrument used for?
Standby instrument powered by a bus
What is a the max range of the DME? (Distance measuring equipment)?
399.9NM
When does ILS generate signals?
For manual or auto precision landings or auto landings in CAT 3
When is the localiser system operative?
25Nm and between 2000ft and 3000ft
When is the glide slope system operative?
10Nms and 2000ft
What is the marker system?
The distance and feet from the threshold of the runway.
These days what is used instead of the marker system?
Short range DME
Where is the localiser antenna located?
Approx 300m beyond the far end of the runway.
What two signals does the localiser antenna send left and right?
150 Hz right and 90 left
How does the aircraft know it is centred when reading the localiser signal?
In the middle the signals are equal, if it biases then the predominant signal is stronger left or right.
What is the beam angle of the localiser?
4 to 5 degrees
When the localiser is operative how often is the station morse ID transmitted?
6 times a minute
Where is the glide slope transmitter located?
1000ft from the beginning of the runway.
What two signals does the glide slope transmitter send out for above and below?
90Hz above
150Hz below
Is the glide slope more or less sensitive than the localiser?
More
Does the glide slope system have a morse ID?
No
Why is the glideslope frequency not tuned seperatly?
Paired with the associated localiser freq
What is the purpose of the marker beacon system?
Indicate to the flight crew that the aircraft is passing over a location such as a point along an instrument landing path.
What three markers should there be for the marker beacon?
Outer, middle and inner
Which marker beacon is quite often not installed?
Inner
What are the frequencies of the marker beacons?
Outer- 400Hz
Middle- 1300Hz
Inner- 3000Hz
What is the carrier freq of marker beacons?
75Mhz
What range of distance is the outer marker beacon?
4 to 7 miles
What does the primary radar system do?
Tracks other objects in the airspace
How does the primary radar system calculate the
(Speed of light x time delay) /2
What primary radar systems are there?
Weather radar
Rad alt
ATC surveillance
What does the secondary radar do?
Serves to complement the primary.
What principle does the secondary radar operate on?
Interrogation response
What examples of secondary radar are there?
ATC
TCAS
DME
How far ahead can the weather radar pick up clouds?
300Nm
What are the five colours on the weather display?
Black
Green
Amber
Red
Magenta
What does black mean on the weather screen?
No turbulence
What does green mean on the weather screen?
Minimum turbulence
What does amber mean on the weather screen?
Moderate turbulence
What does red mean on the weather screen?
High turbulence
What does magenta mean on the weather screen?
Extreme turbulence
How far does weather radar and turbulence mode extend ahead of the aircraft? (WX+t)
40 Nm
What is the basic ATC transponder often referred too as?
SSR, secondary surveillance radar
What frequencies does the ATC system use for position interrogation?
Sends 1030
Receives 1090
What modes of interrogation are there?
A,B,C and D
What happens when the squark ident button is pressed?
Causes the special position indicator to be transmitted for a period of between 15-20 seconds.
What are the three segments of GPS?
User, satellite and control
How many orbits of satellites are there?
6 each with 4 satellites
What is GPS?
Satellite-based navigation system that calculates aircraft positions with high accuracy
What are the two types of GPS service?
Precision and Standard
What is the INS system?
Uses a conventional gyro stabilised platform and accelerometers to provide an update on the current position.
What is INS compared to IRS?
INS is the advanced version of IRS.
What does FANS stand for?
Future Air Navigations Systems
What is FANS?
Navigation system using space-based navigation, such as GPS, and Satellite Communication (SATCOM)
What are the basic modes of GPWS?
Mode 1-7
What do the crew use FMS for?
Enter route and vertical performance flight plan data.
