VOR system
Radio-technical short-range navigation system

Radio-technical short-range navigation system


The main means of short-range navigation in ICAO Organization (ICAO) adopted the VOR system (VOR), BOR / DME (VOR / PMD, VORTAK (VORTAK) and TACAN (TAKAN). These systems operate in the VHF range and provide a definition of the azimuth, range, or both of these values ​​at the same time for the aircraft relative to the ground omnidirectional beacon. the following are the details of the aircraft radio equipment capable of receiving signals omnidirectional beacon VOR. Typically, these radios provide not only receives signals VOR beacon, but the system localizer signals landing ILS (ILS).

Recently, on foreign aircraft, DME rangefinders are being replaced by TAKAN rangefinder equipment, since the rangefinder part of the TAKAN system provides greater accuracy compared to the DME system. In this configuration, the system received the name VORTA K. In addition, the TAKAN system also provides greater azimuth accuracy compared to the VOR beacon, as well as a data link from the aircraft to the ground and back in the TAKAN system. This system gradually replaces the system. 

Radio systems VOR

Samoletnaya equipment VOR - ILS, SR-32 or SR-34 / 35 provides samoletovozhdenie on ground beacons VOR and implementation approach for the ILS system.

When using "VOR" mode, this equipment allows to solve the following navigational tasks:

  • determine the magnetic bearing ground beacon VOR2 to fly by FMF ground beacon;
  • determine the location of the aircraft on the magnetic bearing of the two beacons VOR;
  • to determine the drift angle in flight.

The range of the VOR system (beacons power 200 W) is within the range, km:

Longest distance - when flying over flat terrain and the sea. The accuracy of the VOR bearing beacons using the on-board equipment is characterized, as a rule, a mistake 2-3 °. When flying in mountainous areas errors can reach up to 5-6 °.

Omnidirectional beacon VOR radiates a signal consisting of a carrier (in the range of up to 108 118 MHz) frequency modulated by the two low-frequency signals (30 Hz). The phase difference of the modulating frequencies, measured at any point in the working area beacon proportional azimuth plane relative to a given (reference) direction. Typically, a reference for the direction taken the direction of the north; along this direction both modulating frequencies are in phase.

When driving the plane in a clockwise direction with respect to the installation location of the lighthouse phase one of the modulating frequency changes, while the other phase, which is the standard remains unchanged. This is achieved by a separate light carrier and sideband frequencies, the signals sideband reference phase creates a non-directional in the horizontal plane of the diagram, and signal sideband variable phase creates horizontal directional diagram in the form of eights.

All beacons VOR systems work automatically and managed remotely.

Radio-technical short-range navigation system

Currently installed beacons VOR with tall marker, which, thanks to the signaling transmitted on the board itself

summer can more accurately determine the time span of the lighthouse. In order to distinguish one from another beacon, each of them assigned to their call signs, which are two or three letters of the Latin alphabet, Morse transmitted by telegraph. Listening to these signals in an aircraft is made through the STC.

Ground System Equipment

ILS consists of a localizer and glide path beacons and three marker beacons: long, medium and short-range (currently near the marker is not established at all airports). At some airports, for the construction of the maneuver while landing at the far point the marker or outside (in the course of the zone axis alignment system ILS) installed the drive station.



There are two options for placement of ground equipment:

  • 1) localizer beacon is located on the runway axis;
  • 2) when the localizer is located to the left or to the right of the runway axis so that the heading zone axis passes through the middle or near marker point at an angle of 2-8 ° to the continuation of the runway axis. At many airports, the far ILS marker is set at 7400 m, the middle marker is 4000 m, and the near marker is 1050 m from the start of the runway.

Control units and devices pointers equipment SR-32. To configure the hardware and readings in flight crew uses the following devices:

  • SR-32 control panel; pointer-dial bearing beacon;
  • Two courses, glide the index (zero-LEDs).

Note. Some Tu-104 because of work glide receivers SR-32 and 2-EMG from one antenna is provided antenna relay switch with the inscription "SP-50 - HUD."

Flap control equipment SR-32 and pointer-dial bearing located at the workplace navigator. Dash has two control handles to set the VOR or ILS frequency. When you install the appropriate frequency on the instrument panel pilot lights one of the warning lights labeled "BOP" or "HUD". Course glide path indicators are located on the dashboard of the commander of the ship and right of the pilot. On some aircraft piloting aircraft they provide not only the signals of VOR and ILS beacons, but also allow for the landing system SP-50.



Complete on-board equipment BOP

Sets the currently-board equipment VOR - ILS, SR-34 / 35 has the following control units and pointers:

  • control panel; selector-bearing; radiomagnetic indicator;
  • Two courses, glide the index (zero-LEDs).
  • Flap control apparatus VOR ILS, as in the apparatus SR-32, has two handles for setting the fixed frequency "BOP" or "HUD".
  • The device selector is used to set and the reference values ​​given magnetic bearing beacon (or ZMPU), and the arrow "TO - the FROM" indicates the aircraft position relative to the lighthouse: the position of "TO" ( "ON") - a flight to the lighthouse BOP;

position «FROM» ( «ON») - the flight from the VOR beacon.

For flight at a predetermined track on the selector-azimuth value ZMPU manually set and if the vertical arrow is an Instrument glide slope indicator is held in the center, it can be assumed that the aircraft is on the intended track. The span of the lighthouse is marked by an arrow "TO-FROM». Indications of the arrows depend only on setting the ZMPU and the aircraft relative to the beacon position and does not depend on the magnetic heading of the aircraft. When switching values ​​ZMPU testimony vertical arrows glide an Instrument pointer are reversed.

The radio frequency indicator indicates the MNR values ​​relative to the location of the beacon (from 0 to 360. ") At the same time, the magnetic course of the aircraft and the heading angle of the BOR beacon can be measured on this device. , Since the arrow pointing to the MPR relative to the moving scale simultaneously shows the heading angle of the beacon on the fixed scale. There are two aligned arrows on the RMI that show MNR values ​​from two sets of airborne equipment VOR.

When two sets of avionics VOR-ILS, SR-34 / 35 two control panel are installed, two selector-bearing, two radiomagnetic indicator, two courses glide-pointer (respectively for the first and second pilot).


The use of BOP equipment - the HUD flight

Ground training. To use the apparatus VOR-ILS flight need to know the exact coordinates, frequencies and call signs of terrestrial radio beacons, their location relative to a given track (individual sections of the route).

In order to facilitate the definition and gaskets bearing on the map is applied to the azimuth circle with the center at the installation location beacon with scale division 5e. Zero the scale of these circles is combined with the North on

board of magnetic meridian beacon. In the circle should be the inscription with the name of the item, the location of the beacon frequency of its work and call sign (telegraphic alphabet letters).

To determine the magnetic bearing in flight VOR beacon on the place of the aircraft must perform the following activities:

  • including apparatus VOR ILS and wait 2-3 minutes, until it warms up;
  • set on the remote control beacon frequency;
  • listen to the call sign of the beacon;
  • rotating the focusing ring on the index-bearing adjuster SR-32, to achieve alignment of the double arrow with a single, with the single needle must be between the components of the double arrow and be parallel to it;
  • make sure that the course heading indicator is in the center of the instrument scale and, if necessary, set it in the center of the black circle by turning the focusing ring on the index-adjuster bearings;
  • remove the magnetic bearing beacon count in the counter-pointer set point bearing on the map and pave the line shot MNR.
  • When using the equipment SR-34 / 35 magnetic bearing count pas RMI or by turning the handle installation ZMPU selector-azimuth, seeking for a course-glide installation pointer vertical arrow at zero; then in the selector-azimuth can be read MNR, if the arrow "TO-FROM» is in the "TO".

Note. In flight, the BOP system must remember that the bearing to the beacon of course does not depend on the plane. This system differs from the BOP system "finder - drive radio" when working with the bearing which is the sum of the course and azimuth station.

Flying the VOR beacon for a given magnetic bearing. After takeoff, the crew must be:

  • Turn on the equipment, set the frequency of the beacon on the control panel and listen to its call sign;
  • set the value of the index at a predetermined MPR-bearing adjuster (SR-32) or the selector device bearing (SR-34 / 35);
  • if the rise was not made in the direction of the beacon, then perform a maneuver to enter the line of a given magnetic bearing beacon.

When approaching the aircraft to line MNR single gauge needle-bearing setpoint come to a double arrow (using equipment SR-32).

For accurate line-out to the set MNR crew must deploy the aircraft in proactively turning point. When the plane will fly straight through the set MNR, course hand an Instrument glideslope indicator will be in cents

D unit and single arrows set between the double arrow, and it will be parallel (using onboard equipment SR-32).

Determination of the time to fly over the VOR beacon. With the approach of the aircraft to the VOR beacon celebrated periodical falling out blenker. Course arrow glide an Instrument pointer becomes more sensitive, even with minor deviations of the aircraft from the intended track. A single-arrow pointer setpoint bearing also ranges from ± 5 to ± U ° in both directions.

In the case where, after passing over a beacon provided following the route with the same course of 15-20 km from the time of flight of the beacon is expedient course to withstand not exchange-wise an Instrument glideslope indicator, and on the Code of Civil Procedure (ESP system mode GIC).

Moment overflight beacon celebrated turning arrows indicating MNR on 180 °. This rotation, depending on the altitude and airspeed of the aircraft is made for 2-3 seconds.

Flight from VOR beacon.

For the flight of the aircraft in a given direction from the beacon is necessary: 

  • VI lay on the map desired track;
  • remove from the map the magnetic bearing of the beacon from one point of the characteristic landmarks located on the tracks within range of the beacon;
  • to the obtained value of the MPR add 180 °; after take-off, turn on the BOP equipment, set the frequency of the beacon and listen to its call signs; set the angle MPR + -f- 180 ° on the index set point bearing (SR-32) or instrument-bearing selector (SR-34 / 35).

Depending on the direction of take-off with respect to the direction of flight from the lighthouse to perform a maneuver to enter the line given MNR (line way) that marked the arrival of the vertical arrows glide an Instrument pointer in a vertical position.

Flight of the intended track to perform at the rate of glide-pointer by controlling the value of the testimony of a single ZMPU arrow pointer setpoint-bearing (SR-32) or RMI (SR-34 / 35).

An example of the flight of the lighthouse and the lighthouse with the equipment SR-34 / 35.

Determination of the place the plane on the magnetic bearing of the two beacons VOR with the greatest accuracy is obtained if the flight is conducted "From" or "on" a beacon and a second beacon is on

abeam from the right and left side of the aircraft. Thus bearings of the two beacons form an angle close to 909.


To determine the location of the aircraft must be:

  • remove accurate count bearing beacon located in the alignment of the intended track, and to lay it on the map;
  • GIC withstand course, tune in to the lighthouse, located away from the intended flight path of the aircraft and remove the bearing to the beacon;
  • draw a line with the side bearing the beacon; the intersection of two bearings will place the aircraft, taking into account the correction for movement of aircraft for the laying of bearings on the map.

By the time of flight and the distance between the two marks MS defined direction finding beacons VOR, you can determine the value of the ground speed.

Determining drift angle when flying along the lines of the magnetic bearing beacon VOR ("On" or "On" it) by the formula: a flight to the beacon.

Maneuver to enter the zone of the course beacon of the ILS system. With the help of the VOR-ILS equipment, it is possible to perform a maneuver to descend an aircraft using the signals of the VOR beacon located at the airport and enter the area of ​​the course beacon of the BOR system in the following ways: with a direct; along a large rectangular route; method or procedure turn on the lapel design angle.

The simplest maneuver of descent and entry into the zone of the course beacon of the ILS system is performed then, When VOR beacon located in the alignment of the line planting.

In the case of the approach to the line with a decrease in the course of the approach to the airport crew piloting the aircraft using the VOR beacon of course an Instrument glide arrow pointer to entering the coverage area of ​​the ILS localizer. When landing on the control panel instead of the VOR beacon frequency sets the frequency ILS localizer. Entrance to the area is controlled by HUD beacon warning light with the inscription "HUD" and triggering blenker.

When landing on a large rectangular route the crew determines the tool response equipment VOR ILS turns and moments of entering the zone ILS localizer. For this scheme to reduce and approach pre-calculated values ​​MNR checkpoints. When the coincidence of the calculated and actual values ​​A1PR taken from. The bearing pointer, marked the time span of control points.

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