Navigation Aids

 

VHF OMNI-DIRECTIONAL RADIO RANGE (VOR)

A VHF radio navigational aid provides a continuous indication of bearing from the selected VOR ground station.

The information derived from the VOR signal received at the aircraft may be presented on a combined VOR / ILS Derivation Indicator or on a Radio Magnetic Indicator (RMI).

 

DISTANCE MEASURING EQUIPMENT (DME)

Distance Measuring Equipment (DME) is an ICAO standard short distance navigational aid. It operates in the 1000 MHz band and may compliment a VOR station to provide a more precise navigation service.

The object of airborne Distance Measuring Equipment is to enable a pilot to determine his range from a ground beacon called a Transponder. Ideally this ground DME facility should be co-located with a VOR that is the VOR and DME transponder share the same site (VOR / DME). This being so, the pilot is able to fix his position from the simultaneous range and bearing information provided. Navigation aids providing range and bearing information are referred to as rho-theta aids.

List of Sarawak’s VOR / DME stations:

 
STATION
COMPONENT
ID
FREQUENCY
 
KUCHING
DVOR / DME
VKG

114.5 MHZ
CH 92X
MIRI
DVOR / DME
VMI

112.4 MHZ
CH 71X
SIBU
DVOR / DME
VSI

113.9 MHZ
CH 86X
BINTULU
DVOR / DME
 VBU

112.6 MHZ
CH 73X
LIMBANG
DVOR / DME
VLG

113.4 MHZ
CH 81X
MULU
DVOR / DME
VMZ

112.8 MHZ
CH 75X

The range information obtained from airborne Distance Measuring Equipment (DME) may be used for the following purposes:

 

NON DIRECTIONAL BEACON (NDB)

The Non-Directional Beacon (NDB) and its associated Automatic Direction Finding (ADF) equipment is primarily a short distance Navigational Aid. The Ground Station (NDB) radiates a signal in all direction around the transmitter, and the aircraft receiver (ADF), when tuned to this signal determines the direction from which the signal is being radiated. By following the direction by the ADF instrument the air craft will fly over the NDB.

The system operates in the medium frequency band, i.e. 200 to 400 kHz, however, most aircraft equipments are sufficiently flexible to one or two additional band to be selected so as to extend the use of this facility to cover band utilized by Broadcasting Stations. In isolated cases, NDB are operated in the higher frequency band (1655 kHz) to lessen the reflecting influence of mountainous country.

List of Sarawak’s NDB stations:

 

STATION
COMPONENT
ID
 
KUCHING
AN
402 KHZ
MIRI
MYY
209 KHZ
SIBU
NIS
203 KHZ
BINTULU
BTU
 368 KHZ
MULU
MZU
505 KHZ

 

INSTRUMENT LANDING SYSTEM (ILS)

A precision instrument approach system which normally consists of a VHF Localizer, UHF Glideslope and VHF Marker Beacon.

The Instrument Landing System (ILS) is an instrument presented, pilot interpreted, final approach aid. The system provides the pilot with the instrument indications which, when utilized in conjunction with the normal flight instrument enables the aircraft to be maneuvered along a precise, predetermined, final approach path.

Localizer is the component of an ILS which provides azimuth guidance to a runway. It may be used as part of ILS or independently. A Localizer Radio Beam to furnish directional guidance to and along the Runway.

A Glide Path Radio Beam to furnish vertical guidance at the correct descent angle to the Runway Touchdown Point.

The Function of a Fan Marker / Marker Beacon is to indicate position along an Airway, as well as providing ILS distances from touchdown indication.  Marker Beacon radiates a fan-shaped field pattern and usually consisting two Markers which is Outer Marker and Middle Marker.

However, most installation nowadays replaces this Marker Beacon with Distance Measuring Equipment (DME), which installed co-located with the Glide Path. So the distance from touchdown is determined by DME.

List of Airport in Sarawak with ILS equipped:

AIRPORT
ID
 COMPONENT FREQUENCY
 KUCHING IKG ILS / LLZ 110.3 MHZ
GP / DME 335 MHZ
CH 40X
MIRI IMR  ILS / LLZ 110.10 MHZ
GP / DME 334.4 MHZ
CH38X
SIBU   ILS / LLZ 110.5 MHZ
GP / DME 329.6 MHZ
CH 48X
BINTULU ILU ILS / LLZ 108.7 MHZ
GP / DME 330.5 MHZ
CH 24X

 

 

 RADAR SYSTEM

Radar (coined from the RAdio Detection And Ranging) is an electronic device which can detect and locate objects.

Two types of radar are used in Civil Air Traffic Control – they are Primary Radar and Secondary Surveillance Radar (SSR). Both types locate an object by measuring its range and bearing from the radar head.

SSR differs from Primary Radar in that it requires the active participation of the aircraft.

SSR gives a clearer display because there is no weather or ground returns.

It is easier to identify aircraft on SSR.

Constant flight level information is available on SSR.

Aircraft size is immaterial to detection on SSR.