Guide to air navigation of aviation of the Russian Armed Forces. Navigation and Aircraft FAQ

Knowledge of some principles easily compensates for ignorance of some facts.

K. Helvetius

What is Air Navigation?

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The modern term “air navigation”, considered in a narrow sense, has two interrelated meanings:

• a certain process or activity of people occurring in reality to achieve a certain goal;
  • Air navigation – control of the aircraft trajectory carried out by the crew in flight. The air navigation process includes the solution of three main tasks:
    • formation (selection) of a given trajectory;
    • determining the location of the aircraft in space and the parameters of its movement;
    • formation of a navigation solution (control actions to guide the aircraft onto a given trajectory);
• the science or academic discipline that studies this activity.
  • Air navigation as a science and academic discipline. Air navigation is the applied science of precise, reliable and safe driving of aircraft from one point to another, and the methods of using technical navigation aids.

What books on air navigation are best to read first?

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What devices provide air navigation processes on an airplane?

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• The composition of the instruments may vary, depending on the type of aircraft and the era of its use. The set of such devices is called a flight navigation system (FNS). Air navigation technical aids are divided into the following groups:
• Geotechnical means. These are means whose operating principle is based on the use of the physical fields of the Earth (magnetic, gravitational, atmospheric pressure fields), or the use of general physical laws and properties (for example, the properties of inertia). This largest and oldest group includes barometric altimeters, magnetic and gyroscopic compasses, mechanical watches, inertial navigation systems (INS), etc.
• Radio equipment. Currently, they represent the largest and most important group of means that are fundamental in modern air navigation for determining both the coordinates of the aircraft and the direction of its movement. They are based on the emission and reception of radio waves by on-board and ground-based radio devices, measuring the parameters of the radio signal, which carries navigation information. These tools include radio compasses, RSBN, VOR, DME, DISS systems and others.
• Astronomical means. Methods for determining the location and course of a ship using the celestial bodies (Sun, Moon and stars) were used by Columbus and Magellan. With the advent of aviation, they were transferred to air navigation practice, of course, using technical means specially designed for this - astrocompasses, sextants and orientators. However, the accuracy of astronomical aids was low, and the time required to determine navigation parameters with their help was quite large, therefore, with the advent of more accurate and convenient radio engineering aids, astronomical aids were beyond the scope of the standard equipment of civil aircraft, remaining only on aircraft flying in polar regions. areas.
• Lighting equipment. Once upon a time, at the dawn of aviation, light beacons, like sea lighthouses, were installed at airfields so that at night a pilot from afar could see it and go to the airfield. As flights increasingly began to be carried out using instruments and in adverse weather conditions, this practice began to decline. Currently, lighting equipment is used mainly during landing approaches. Various systems of lighting equipment allow the crew at the final stage of approach to detect the runway (runway) and determine the position of the aircraft relative to it.

How to deal with altitude, pressure, QNE, QFE, QNH and more?

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• Reading the article by Sergei Sumarokov "Altimeter 2992"

Where can I get the route to create a flight plan?

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The routes are laid along the most optimal routes, while trying to provide the shortest routes between airports, and at the same time taking into account the need to bypass restricted areas (test airfields, Air Force flight zones, training grounds, etc.). At the same time, the routes laid along sections of these routes are, if possible, closer to orthodromic ones. Routes are listed in special collections, for example List of air routes of the Russian Federation. In collections, the route is indicated by a list of sequentially listed waypoints. Radio beacons (VOR, NDB) or simply named points with fixed coordinates are used as waypoints. In a graphical representation, the routes are plotted on radio navigation maps (RNA).

A very convenient and visual website for planning routes skyvector.com

• If you want realism, you need to use ready-made routes. For example,
• Routes for the CIS on infogate.matfmc.ru
  • there is a similar, but slightly outdated database -
• You can compile it yourself using RNA or Lists of air routes
• Skyvector.com - a very convenient interface for creating your own route or analyzing existing routes
• There are specialized sites for generating virtual routes, for example:
  • SimBrief review of the site
  • Displaying ready-made routes on the map

• Also check out these sites:

In general, the route looks like this: UUEE SID AR CORR2 BG R805 TU G723 RATIN UN869 VTB UL999 KURPI STAR UMMS

We remove the codes of departure and arrival airports (Sheremetyevo, Minsk), the words SID and STAR indicating departure and arrival patterns. It should also be noted that if there is no route between two points and this section runs directly (which is very common), it is indicated by the DCT sign.

AR CORR2 BG R805 TU G723 RATIN UN869 VTB UL999 KURPI, where AR, BG, TU, RATIN, VTB and KURPI are PPM. The routes used are marked between them.

What are approach patterns, Jeppessen, SID, STAR and how to use them?

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If you are going to take a certain level to the point of completion of the descent, then the vertical speed ( Vvert) is determined through three variables:

• ground speed ( W);
• height to be “lost” ( N);
• the distance at which the descent will be performed.

How to learn to use RSBN and NAS-1

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Problems with RSBN An-24RV Samdim

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Possible problems with the RSBN for this aircraft are collected in the An-24 FAQ

Basic navigation parameters in English terminology

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• True North- North Pole, the vertical axis of sectional charts, meridians
• Magnetic North- Magnetic Pole, earth's magnetic lines of force affecting the compass.
• Variation- angular difference between true north and magnetic north. The angle may be to the east or west side of north. Eastern variation is subtracted from true north (Everywhere west of Chicago) and western variation (Everywhere east of Chicago) is added to obtain magnetic course. East is least and West is best: memory aid for whether to add or subtract variation. West of Chicago it is always subtracted.
• Isogonic lines- Magenta dashed lines on sectional showing variation. VOR roses have variation applied so that variation can be determined by measuring the angle of the North arrow on the rose from a vertical line.
• Deviation- Compass error. A compass card in the airplane tells the amount of error to be applied to magnetic course to obtain compass course. Make a copy to keep at home for planning purposes.
• True Course- The line drawn on the map. Draw multiple lines with spaces //// from airport center to airport center. Multiple lines permit features chart to be read.
• Magnetic Course- True Course (TC) +/- variation = Magnetic Course. Put Magnetic Course on sectional for use while flying. This course determines hemispheric direction for correct altitude over 3000" AGL.
• Compass Course- Magnetic Course minus deviation gives Compass Course. The difference is usually only a few degrees.
• Course- A route which has no wind correction applied
• Heading- a route on which wind correction has been applied to a course.
• True Heading- angular difference from true course, the line on the chart, caused by the calculated wind correction angle ( W.C.A.).
• Magnetic Heading- angular difference from magnetic course caused by wind correction angle; also, obtained by applying variation to true heading.
• Compass Heading- angular difference from compass course caused by wind correction angle; also, obtained by applying deviation to magnetic heading. If wind is AS computed, this is the direction you fly.
• True airspeed- Indicated airspeed corrected for pressure, temperature, and instrument error. This is found in the aircraft manual. Cessna is overly optimistic in its figures.
• Ground speed- actual speed over the ground. This is the speed on which you base your ETA"s
• Wind Correction angle- angular correction in aircraft heading required to compensate for drift caused by wind. Correctly computed it will allow the aircraft to track the line drawn on the chart.
• Indicated altitude- Altimeter reading with Kollsman window set for local pressure and corrected for instrument error.
• Pressure altitude- altimeter reading with Kollsman window set for 29.92. Used for density altitude and true airspeed computations.) Temperature is not used in determining pressure altitude.
• True Altitude- distance above datum plane of sea level
• Density Altitude- Pressure altitude corrected for temperature. This is the altitude that determines aircraft performance.

The simulator displays incorrectly... (day, night, time, Moon, stars, road lighting)

• the change of night and day
  • to discuss the correct change of day, night, time...

• • And if you want realism, never install any FS RealTime, TzFiles, etc. The simulator displays the movement of luminaries and illumination according to real astronomical laws. For example,

• time
  • Realistic onboard clock. In particular, they do not spontaneously switch between time zones.
• change of moon phases
  • RealMoon HD Realistic Moon textures (FS2004, FSX)
  • to the website
• starry sky
  • Reading the article "Navigation luminaries". At the end there are links to help you make a realistic view of the starry sky in FS2004. This is done by replacing the stars.dat file.

Intensity = 230 NumStars = 400 Constellations = 0

• roads glow at night

We find files in this path: Your drive:\Your Sim folder\Scenery\World\texture\

Air navigation: goals and methods Air navigation is the applied science of methods and means of forming a given space-time trajectory of an aircraft (Aircraft) Dead reckoning Positional Methods -Advantage: navigation autonomy. -Limitations: a) accuracy decreases over time b) strict requirements for measurement continuity - Advantage: high accuracy and immediacy of measurements - Limitations: a) the need for ground (and space) infrastructure b) limited coverage. Overview-Advantage: ease of implementation comparative -Limitations: requires special conditions

Radio navigation methods Dead reckoning methods Positional methods Extreme correlation methods Based on the measurement and integration of the components of the aircraft speed relative to the earth's surface Based on finding lines or surfaces of position Based on the comparison of some physical parameters observed using on-board sensors that characterize the terrain (relief heights) with reference ones stored in system memory

Radio navigation aids for flight support A set of onboard and ground components of radio navigation systems (RNS) and devices (RNU) that provide a solution to the main task of navigation - the implementation of a given space-time flight path. The onboard part from the radio navigation field extracts the flight navigation parameter and creates a radio navigation field. Ground part Orbital part of the RNS. are radio engineering information retrieval systems

Navigation parameters and flight elements Navigation flight elements (NF) Scalar quantities characterizing the position of the center of mass of the aircraft and its movement in space Geometric or physical quantity, the value of which Navigation depends on the navigation flight parameters (NF) of the flight element. NP - measured NE.

Radio navigation measurements Flight navigation elements (FN) Aircraft Navigation information sensor Radio signal parameter Flight navigation parameter (FN) Radio navigation field Radio navigation beacon

Navigation elements related to airspeed Navigation speed triangle True air speed True Air Speed ​​(TAS) Drift angle* Drift Angle V U Wind speed Wind Speed ​​W Ground speed* Ground Speed ​​* - element measured by radio navigation equipment

Navigation elements associated with the flight direction NM Magnetic heading Magnetic course Magnetic course Magnetic course angle V U W Course: magnetic MK true (true) IR compass CC orthodromic OK Course is the angle in the horizontal plane between the direction taken as the origin at the aircraft location point and projection onto this plane of its longitudinal axis. The angle between the direction of the true and magnetic meridian is called magnetic declination Δ M

Features of terminology Radio equipment Magnetic bearing Magnetic bearing Beacon VOR Radial Radial Radar Azimuth Azimuth Radio direction finder Bearing QDR Beacon NDB Bearing Reciprocal bearing

Relative position navigation elements(2) Distance(slanted) Altitude Height* Slanted range* Distance Horizontal range Elevation angle* Elevation angle Beacon

Aircraft position (MS) Aircraft position is a projection of the spatial position of the aircraft on the surface of the earth, described by coordinates Coordinate system Geodetic (geographic) * Geospherical Orthodromic Polar * Coordinates Latitude B, longitude L, altitude H Latitude φ, longitude λ, altitude h Distance S, lateral deviation Z, altitude H Azimuth, range, elevation angle θ

The physical nature of radio navigation is based on two main properties of electromagnetic waves: Constancy of the speed of propagation of radio waves. The speed of propagation of radio waves in a medium with a refractive index n is defined as v= =с/n, where с =299,792,456.2 ± 1.1 m/s - speed radio waves (speed of light) in a vacuum. In approximate calculations, the influence of n is not taken into account and n=c=300,000 km/s=3 -108 m/s is taken. For a standard atmosphere (pressure 101.325 kPa, temperature 4 -15 ° C, relative humidity 70%), the propagation speed decreases to 299,694 km/s, which is explained by an increase in the refractive index of radio waves. Changes in speed and changes in atmospheric parameters are taken into account in high-precision RNU. Propagation of radio waves along the shortest distance between the points of emission and reception. Propagation of electromagnetic waves along the shortest path between the points of emission and reception is possible only in free space. In practice, radio waves, when reflected from the ionosphere and various objects, due to ionospheric and tropospheric refraction, diffraction and some other factors, deviate from the line corresponding to the shortest distance. This circumstance must be taken into account in high-precision RNU.

Classification of radio navigation aids By type of informative parameter of the radio signal Amplitude, time, phase, frequency By type of navigation parameter Rangefinders, goniometers, difference rangefinders, speed meters By degree of autonomy Autonomous, non-autonomous single-position, non-autonomous multi-position By purpose Landing systems, long-range navigation systems, short-range navigation systems, global navigation systems

Positional methods The general principle of determining the position of an aircraft in relation to navigation landmarks is implemented in the form of a generalized method of surfaces and position lines. Position surface is the geometric locus of points in space in which the value of the navigation parameter is constant Bearing=const R=const

Determination of the spatial location of the aircraft Ra Rb pms Rc To determine the pms, 3 position surfaces are required

Lines of position Line of position (LP) – the line of intersection of the position surface with the earth’s surface – the geometric location of the points of the probable MS. The value of the navigation parameter at each point of the position line is constant. The point of intersection of two lines determines the location of the aircraft (MS). In radio navigation, the following main types of position line are used: Lines of equal bearings of aircraft range differences Line of Position (LOP)

Positioning along lines of equal bearings of the aircraft This method is implemented in goniometric radio navigation systems Nm Nm MPSV MPSA A B MS Direct - on the plane Orthodromic - on the sphere 1) 2 VOR 2) 2 NDB 3) VOR+NDB

Positioning along lines of equal ranges (distances) Circle – on a plane This method is implemented Circle – on a sphere in rangefinder radio navigation systems 1) 2 DME+ 2) 3 DME 3) GNSS* Rb B A С Ra Rc

Positioning along a line of equal ranges and a line of equal bearings Nm VOR -DME Ra A MPSA

Positioning along lines of equal differences in ranges (distances) Hyperbola – on a plane Spherical hyperbola – on a sphere A Loran-C B Ra-Rc= -const 1 Rb-Rc= - const 2 Ra=Rc Rb=Rc Ra-Rc=const 1 C Rb-Rc=const 2

Calculation of the aircraft's bearing when measuring the course angle NM Magnetic bearing Magnetic bearing of the MPR beacon NM Xc Course angle of the KUR beacon Relative bearing Magnetic bearing(reciprocal) Magnetic bearing of the aircraft MPS MPR= KUR + MK MPS= MPR± 180+δm~ MPR± 180 ~

RNS working zones Factors limiting the working zone 1. Line of sight 2. Transmitter power - receiver sensitivity 3. Geometric factor 4. Near zone of antenna systems 5. “Dead” zone of antenna systems 5. Permissible value of navigation error Working zone - area in space, within which the parameters of the radio navigation field and the accuracy of the RNS meet the specified requirements

Navigation parameters measured by the NDB-ADF system Radio Magnetic Direction Indicator (RMDI) NM Magnetic bearing NDB Magnetic bearing of the MPR beacon NM Xc ADF Course angle of the KUR beacon Relative bearing NDB Reciprocal bearing Magnetic bearing of the aircraft MPS MPR= KUR + MK MPS= MPR± 180+ δm~ MPR± 180 When using RMDI, you can determine: MK, MPR, MPS, CUR

Automatic radio compass ADF Range up to 300 km (70 µm V/m) Relative Bearing parameter (RCC) Frequency 190… 1750 k. Hz Wave range LW, MW Ground beacon NDB (PRS) Accuracy (95%) 2 degrees (5 – Appendix 10) On-board equipment ADF (ARK) Type of radiation MCW or CW NDB Relative Bearing Heading angle ADF Bearing Indicator (ICU) Xс

Structure of the ADF radio compass Directional antenna Radio receiver Control panel (tuning frequency, operating mode) Omnidirectional antenna Heading angle measurement channel Operating modes: - main ADF - listening ANT - internal modulation BFO

NDB range D The NDB range is limited to the zone within which a field strength E of at least 70 microns is created. V/m. The direction finding range is influenced by the following factors: - radiation power of the NDB transmitter - time of day - the presence of lightning activity zones between the aircraft and the NDB - electrification of the aircraft - frequency range The range is indicated by the nearest multiple of 25 nm (46.3 km) with D not exceeding 150 nm ( 278 km), or the nearest multiple of 50 nm (92.7 km) with D greater than 150 nm NDB range is not limited to line of sight

Types of beacons NDB Beacon class Guaranteed range nm (km) Designation Power in table. “Navaids” of the collection transmitter W Jepessen Route NDB HH no less than 200 75(140) Route NDB H from 50 to 200 50 -74 (93 -140) Route NDB HM no more than 50 25 -49(46 -91) Low-power NDB HO – Compass Locator no more than 25 to 26(46) Low-power NDB included in the ILS HL - Locator no more than 25 to 26(46) If NDB is used as part of the ILS, the NDB is combined with a marker beacon)

Navigation application NDB Determination of the aircraft's position using two NDB beacons Determination of equal bearings along two lines, using the aircraft's magnetic bearings from two NDBs: MPS= MK+KUR± 1800 NDB orientation, triangulation) Flight along a track passing through two NDB Maintaining KUR 1= 00, KUR 2=1800 Flight on NDB Flight along a radiodrome, keeping KUR=00 (Homing) Formation of a flight pattern (arrival, approach, departure), using NDB Performing certain maneuvers at given values ​​of KUR or MPS (Holding, approach, circling, etc .)

Application of NDB in ATS Control of aircraft position while flying along an airway Defining a network of airways/routes using NDB Using appropriate procedures to ensure horizontal separation Providing flight in holding areas and during approach

NDB designations on maps On aeronautical maps, NDB installation locations are marked with the following indication: - NDB symbol; The symbol * before the frequency indicates - name; that NDB does not work constantly - transmission frequency (k. Hz); Underlining call signs indicates - letter call signs; that listening via ADF is possible - call signs in Morse code only in BFO mode - geographic coordinates - magnetic meridian indicator arrow.

Beacon equipment NDB Call sign generator Carrier frequency generator Control and remote monitoring device Power modulator and amplifier BITE antenna system

VHF Omnidirectional Range beacon (VOR) Range 300… 320 km (line of sight) 80… 100 km(RNP 5) NM Accuracy(95%) 1. . . 2 degrees (5, 2 - total according to the requirements of Appendix 10) Parameter Magnetic Bearing (Radial) Frequency 108… 118 MHz (160 k) VHF range Ground beacon VOR Airborne equipment VOR Magnetic Bearing (Radial) VOR

Navigation parameters measured by the VOR system NM Magnetic bearing VOR Magnetic bearing of the beacon MPR NM Xc VOR receiver VOR Radial Magnetic bearing of the aircraft MPS MPR=MPS± 180 KUR=MPR-MK When using RMDI you can determine: MK, MPR, MPS, KUR can also be obtained lighthouse call sign and weather report. Course angle of the KUR beacon Relative bearing

Structure of on-board VOR equipment Omnidirectional antenna Radio receiver Channel for isolating the reference phase signal Control panel (tuning frequency) Channel for isolating the variable phase signal Phase difference (radial) calculation device Radial RMDI heading angle calculation device HSI-Horizontal Situation Indicator CDI-Course calculation device Deviation Indicator

VOR beacon structure Call sign generator Master oscillator Amplitude modulator Power amplifier 9960 Hz Low frequency generator Variable Remote control device Frequency modulator Subcarrier frequency generator Reference BITE Electronic goniometer 30 Hz Control and remote monitoring device

VOR range On aeronautical maps, VOR installation locations are indicated, indicating: - symbol; - Name; - operating frequency; - letter call signs; - geographical coordinates. The range is limited to (whichever is less): -line of sight; - a zone within which a field strength E of at least 90 μm is created. V/m; - the specified value of the linear error in determining the position line (62 nm for RNP 5).

Types of VOR beacons Beacon class Designation Height range, ft. (m) Guaranteed range nm (km) High Altitude H 45000. . . 18000(13700... 5500) 130(240) High Altitude H 18000... . 14500(5500... 4400) 100 (185) High Altitude H 14500... . 1000(4400... 300) 40(74) Low Altitude L 18000... . 1000(5500... 300) 40(74) Terminal T 12000... . 1000(3600... 300) 25(46)

Navigation application VOR Determination of the aircraft's position using two VOR beacons Determination of equal bearings along two lines, using the aircraft's magnetic bearings from two VORs (VOR orientation, triangulation) Flight along the line Maintaining equality (Tracking): the path passing Radial = Specified Track Angle with indication On -From (To-From – Reverse sensing) via VOR Flight on VOR over the shortest distance Flight along an orthodrome formed by measuring a given heading angle Formation of a flight pattern (arrival, approach, departure) using VOR Performing certain maneuvers at given radial values ​​(holding , approach, circling, etc.)

Determining the aircraft position using VOR As the distance to the beacon increases, the determination error increases Magnetic bearing(Radial) A Nm Positioning (triangulation) Nm VOR A VOR B Magnetic bearing(Radial) B

Flight along a track line passing through VOR En-route stabilization Nm Magnetic bearing MB (radial) Desired course DC LZP - line of a given path VOR MB=DC on desired track Radial=ZPU on LZP To Fr DC CDI-Course Deviation Indicator NPP-navigation planning device

Application of VOR in ATS Monitoring the position of an aircraft when flying along an airway Defining a network of airways/routes Using appropriate procedures to ensure horizontal separation Ensuring flight in holding areas Constructing SID, STAR, Approach schemes

Limitations and disadvantages of VOR The indicated disadvantages determine the tendency for VOR to be taken out of service and the transition to navigation Relatively low accuracy according to DME Line of sight Linear dependence of the measurement error on the distance to the beacon The need to take into account the geometric factor when positioning using VOR High sensitivity of accuracy to the underlying surface near (300 m) beacon Some of the listed shortcomings are eliminated in Doppler VOR (DVOR)

Range measurement equipment DME (Distance Measuring Equipment) 1. Range 300… 370 km (line of sight) 2. Accuracy (95%) ± 0.2 nm or 0.25%D (or 0.25 nm ± 1.25%D ) 3. Parameter Range (Slant Range Distance) (slant range from the aircraft to the ground beacon) 4. Frequency 962(960)… 1213(1215) MHz 5. Number of channels - 252 6. Range - UHF 7. Ground beacon-transponder ( transponder)DME 8. On-board equipment – ​​interrogator DME 126. 8 NM request DME response

Operating principle of DME (1) Interrogator (aircraft range finder) Trigger generator 1 Transmitter pr antenna Meter Δt 7 pr fi pr antenna 3 Load limitation unit 5 f. R Receiver 8 Delay unit 4 antenna 2 The “request-response” principle leads to a capacity limitation (100 aircraft (now 200)) Receiver prm Transmitter 9 Gain control Transponder (relay beacon) 6

DME equipment signals Code interval between pulses τ Ground-to-air (answer D) 1025. . . 1150 MHz 962. . . 1213 MHz fi f. R=fi - 63 MHz Code interval between pulses τ11=12 µs τ21=12 µs Frequency y Air-ground (request D) Frequency x Parameter Frequency range Code fi f. R=fi + 63 MHz Code interval between pulses τ12=36 μs τ22=30 μs

Structure of on-board DME equipment Omnidirectional (whip) antenna Antenna switch Receiver (response pulse decoder) Control panel (channel number (1 -126) and type (x/y) Transmitter (request pulse shaper) Tracking range meter Range

Limiting the load of the DME relay beacon When the number of interrogators in the beacon coverage area increases above 100 (currently 200), those interrogators that are located further from the beacon are not served. This occurs by decreasing the sensitivity of the beacon receiver as the number of requests per second increases. Repetition frequency of response pulse pairs, Hz Response-response ratio probability of receiving a response to a request 2700 ± 90 1.0 700 Without taking into account the influence of call sign 0.84 0.5 100(200) Number of interrogators (aircraft)

Range DME IPR CH 40 X Altitude, km. . . _ _. 1 k. W 4 k. W 16 k. W Range, km DME installation locations are marked on aeronautical maps indicating: - symbol; - Name; - channel number and type; - letter call signs; - geographical coordinates. The range is limited to: - line of sight (for class H beacons); - the zone within which the power flux density from the ground beacon is created - 83 d. B/(W m 2), i.e., the power of the ground beacon transmitter; - transmitter power of on-board equipment;

Types of DME beacons Beacon class (by emitted power) H High Altitude L Low Altitude T Terminal Beacon type (by signal format) DME - N DME-W DME -P Interface with the VOR/DME ILS/DME MLS/DME -P system

Navigation application of DME Determining the position of an aircraft using VOR/DME Determining the position (polar coordinates) along a line of equal bearings from VOR and a line of equal distances from DME (VOR and DME combined) 2 D - navigation Determining a position along 2 (or 3) lines of equal distances from 2 (or 3)DME Determination of the range to important points of the route: -to WPT (waypoint), which has VOR/DME; Definition - to landing point (ILS/DME); range to the point - to the installation point of the DME-P beacon as part of the MLS Flight along a line of equal ranges (arc) Flight along an arc formed by maintaining a given distance from the beacon Formation of arrival and departure patterns using VOR/DME Performing certain maneuvers at given values radial and range (holding, approach, circling, etc.)

Solution of the navigation problem using DME The ambiguity of the reading occurs only in the manual version of using the method. For the on-board computer, there are two options for iterative algorithms: -calculation of latitude, longitude, altitude by three. D; -calculation of latitude, longitude by two. D and height. DME B DME A DME-DME (2 -D) Positioning 2 D navigation is a very promising method for determining the position of an aircraft, although it requires taking into account the geometric factor and eliminating ambiguity

Phase 1 of the introduction of RNAV (area navigation) in Europe 1998 -2002 Since 2002, the introduction of RNAV zones with random routes is envisaged. On routes In TMA areas B-RNAV airborne equipment is mandatory Possible introduction of B-RNAV routes into TMA (where appropriate) VOR/DME remains to support routine navigation Local ATS routes may be used in the lower airspace DME becomes the primary navigation aid Possible introduction of RNAV procedures, incorporating RNP 1 or better requirements Existing SIDs and STARs remain

Application of DME in ATS Monitoring the position of an aircraft when flying along an air route Using appropriate procedures to ensure horizontal separation Construction of SID, STAR, Approach schemes Providing instrumental categorized approach (ILS/DME, MLS)

Limitations and disadvantages of DME Despite these disadvantages, DME is the most accurate of ground-based radio navigation aids, which determines the trend of VOR decommissioning and the transition to DME navigation Limited coverage (line of sight) Limited capacity (200 aircraft) The need to take into account the geometric factor when DME Positioning Need for Disambiguation in DME Positioning

Main aspects of combining VOR and DME beacons VOR/DME is an angle-measuring radio navigation system, with the help of which its polar coordinates relative to the beacon (radial and range) are determined on board the aircraft. Placement Beacon antennas can be located: coaxially; together (spacing no more than 180 m); separately Coordinates When the VOR and DME class “H” antennas are separated by a distance of more than 180 m, “Not Co-located” is indicated on the maps, and the coordinates are shown from the VOR beacon Call sign Both beacons emit the same call sign

Joint operation of DME with VOR, ILS, MLS beacons When using DME together with ILS and VOR systems, the communication channels of the DME system are paired with the channels of these systems, while only 200 frequency-code DME channels are used. Channels with request frequencies 1. . . 16 and 60. . . 69 are not used When using DME-P as part of MLS, only 200 DME frequency-code channels are also used, but potentially the number of DME-P channels can be increased by expanding the frequency range (960 -1215 MHz) and introducing additional W and Z codes

Instrumental landing system ILS (Instrument Landing System) Localizer (localizer) - range 46 km (25 nm) - frequency 108… 112 MHz (step 50 kHz) Final Approach Fix Height 60 m Height 30 m Outer Glide path equipment marker ( glide path beacon) Glide path External - range 18 km (10 nm) marker - frequency 329 ... 335 MHz (step 150 kHz) - glide path angle Middle marker Landing point Middle marker 2. 7 degrees (2... 4) Internal marker Both beacons have 40 frequency channels Inner marker All marker beacons operate Glide path beacon at the same frequency 75 MHz Glide path equipment (Glide Slope-USA) L Localizer beacon G

Navigation and landing parameters measured by the ILS system (2) L G L L G G Δθ – angular deviation from the glide path plane Δθ

Navigation and landing parameters measured by the ILS system (3) Outer marker Middle marker Inner marker Moments of overflight of poppies located at a known distance from the runway threshold

ILS Landing System Beacons Placement Cat III Parameter Decision Height (DH) 60 m (200 ft) 30 m (100 ft) 0 Runway Visual Range (RVR) 800 m 400 m A-200 m B-50 m C-0 Final Approach Fix TVG DH Cat II 400 -1100 m 60 m 30 m Touch Down Point 120 -180 m 250 -450 m (300) Transmits call sign 75 -450 m 1050 m Modulation 3000 Hz 1300 Hz Point manipulation 6500 -11000 m Modulation 4 00 Hz Dash-dot-dash manipulation

Accuracy characteristics of ILS Localizer (localizer) - error Cat I - ± 10.5 m Cat II - ± 7. 5 m 2σ Cat III - ± 3. 0 m Glide path equipment (glide path equipment) - error Cat I - ± 7. 5% Cat II- ± 7.5% 2σ Cat III- ± 4. 0% Heading channel ± 14 m ± 8 m ± 4 m Glide path channel ± 1 m ± 0.4 m Linear error is determined at the runway threshold

Requirements for landing systems General accessibility requirement for landing 0.99999 Integrity Category CAT III Risk Warning time 2 x 10 -7 6 s 2 x 10 -7 1 x 10 -9 2 s 2 s Requirements for integrity and continuity Continuity 8 x 10 -6 (15 s) 4 x 10 -6 30 s

Marker radio beacons Marker beacons are designed to determine: - the passage of fixed points; - flight of a given point at a distance; - flight of a given point in height; - the moment of reaching DA/H or MDA/H. (VLOOKUP for precision or non-precision approach systems). . Marker beacons operate at a fixed frequency of 75 MHz, and the signal radiation pattern is directed upward. Route marker beacons are divided into classes. 1. Marker beacons of the FM class (Fan Marker) have an elliptical shape of the radiation pattern in the horizontal plane, and are used to record the moment of passage of a certain point on the route. Marker beacons of the FM class with a dumbbell-shaped (Bone) radiation pattern in the horizontal plane are used to control the passage of a fixed point over time. Route marker beacons have a signal emission power of about 100 watts. 2. Marker beacons of the LFM class - Low Powered Fan Marker - with a transmitter radiation power of 5 watts. have a circular radiation pattern. 3. Z marker - designed to signal the passage of a certain point on the approach diagram, with a transmitter radiation power of the order of 3 - 5 watts. In the ILS system these are outer, middle and near markers (OM, MM, IM.)

Limitations and disadvantages of ILS Limited operating area Fixed glide path for all aircraft Strong influence on the performance of weather conditions Strong influence on the parameters of the reflector system near the beacon antennas

Along a given space-time trajectory.

Air navigation tasks

• • coordinates (geographic-->latitude, longitude; polar-->azimuth, range)
  • height (absolute, relative, true)
  • altitude above the Earth's surface (true flight altitude)
  • well
  • track angle (conditional, true, magnetic, orthodromic)
  • indicated, true, ground speed
  • speed, direction (meteorological, navigation) and wind angle
  • specified path line (LPL)
  • linear lateral deviation (LBU)
  • additional correction (AC) (when flying to a radio station)
  • lateral deviation (SB) (when flying from a radio station)
  • reverse, forward bearing (OP, PP) (when flying to/from a direction finder)
• Control and correction of the path: (With access to the LZP or to the PPM (turning point of the route), depending on the LBU and ShVT)
  • by range
  • towards
• Laying and dead reckoning:
  • Straight
  • Reverse
  • Calm
• Building optimal routes to reach your destination
  • reaching the point in the minimum time
  • reaching the point with minimal fuel consumption
  • reaching a point at a given time
• Prompt route correction during flight
  • when the flight mission changes, including in the event of malfunctions in the aircraft
  • in the event of adverse meteorological phenomena along the route
  • to avoid collision with another aircraft
  • to approach another aircraft

Determination of aircraft navigation elements

Various technical means are used to determine navigation elements:

• Geotechnical- allow you to determine the absolute and relative altitude of the flight, the course of the aircraft, its location, and so on).
  • air and ground speed meters,
  • magnetic and gyromagnetic compasses, gyro-semi-compasses,
  • optical sights,
  • inertial navigation systems and so on.

• Radio engineering- allow you to determine the true altitude, ground speed, location of the aircraft by measuring various parameters of the electromagnetic field using radio signals.
  • radio navigation systems and so on.

• Astronomical- allow you to determine the course and location of the aircraft
  • astronomical compasses
  • astro orientators and so on

• Lighting- provide landing of the aircraft in difficult weather conditions and at night and to facilitate orientation.
  • light beacons.

• Integrated navigation systems- autopilot - can provide automatic flight along the entire route and landing approach in the absence of visibility of the earth's surface.

Sources

• Cherny M. A., Korablin V. I. Aircraft navigation, Transport, 1973, 368 p. broken link

Wikimedia Foundation.

• 2010.
• Space navigation

Inertial navigation

See what “Air navigation” is in other dictionaries: Air navigation - a set of crew actions aimed at achieving the greatest accuracy, reliability and safety of driving an aircraft and groups of aircraft along a given trajectory, as well as for the purpose of bringing them in place and time to specified objects (targets) ...

Official terminology Air navigation

- Air navigation, air navigation is the science of methods and means of driving an aircraft along a program trajectory. Air navigation tasks Determination of navigation elements of an aircraft latitude, longitude altitude LUM height above the surface ... ... Wikipedia- (Latin navigatio from navigo sailing on a ship), 1) the science of ways to choose a path and methods of driving ships, aircraft (air navigation, air navigation) and spacecraft (space navigation). Navigation tasks: finding... ... Big Encyclopedic Dictionary

navigation- And; and. [lat. navigatio from navigo sailing on a ship] 1. Shipping, seafaring. Due to the shallowing of the river N. impossible. 2. Such a time of the year when navigation is possible due to local climatic conditions. Opening navigation. The ships in the port were waiting for the start... ... encyclopedic Dictionary

Navigation- Wiktionary has an article “navigation” Navigation (lat. navigatio, from lat. navigo sailing on a ship): Navigation, navigation The period of time in the year when, due to local climatic conditions, it is possible to sail ... Wikipedia

navigation Encyclopedia "Aviation"

navigation- Rice. 1. Determining the location of the aircraft using position lines. navigation of aircraft, air navigation (from Greek aēr air and Latin navigatio navigation), the science of methods and means of driving aircraft from ... ... Encyclopedia "Aviation"

- Air navigation, air navigation is the science of methods and means of driving an aircraft along a program trajectory. Air navigation tasks Determination of navigation elements of an aircraft latitude, longitude altitude LUM height above the surface ... ... Wikipedia- (Latin navigatio, from navis ship) 1) navigation. 2) the science of steering a ship. Dictionary of foreign words included in the Russian language. Chudinov A.N., 1910. NAVIGATION 1) the art of steering a ship in open air. sea; 2) time of year, in... ... Dictionary of foreign words of the Russian language

Navigation (marine)- Navigation (lat. navigatio, from navigo - sailing on a ship), 1) navigation, shipping. 2) The period of time in the year when navigation is possible due to local climatic conditions. 3) The main section of navigation, in which theoretical ... Great Soviet Encyclopedia

- Air navigation, air navigation is the science of methods and means of driving an aircraft along a program trajectory. Air navigation tasks Determination of navigation elements of an aircraft latitude, longitude altitude LUM height above the surface ... ... Wikipedia- NAVIGATION, and, women. 1. The science of driving ships and aircraft. School of navigation. Air n. Interplanetary (space) n. 2. The time during which shipping is possible, as well as shipping itself. Start, end of navigation. N. is open. |… … Ozhegov's Explanatory Dictionary

It would seem that the fastest and most convenient way is to fly in a straight line between two airports. However, in reality, only birds fly along the shortest path, and airplanes fly along airways. Air routes consist of segments between waypoints, and the waypoints themselves are conventional geographic coordinates, which, as a rule, have a specific, easy-to-remember name of five letters, similar to a word (usually in Latin, but transliteration is used in Russian). Usually this “word” does not mean anything, for example, NOLLA or LUNOK, but sometimes it reveals the name of a nearby settlement or some geographical feature, for example, the OLOBA point is located near the city of Olonets, and NURMA is the vicinity of the village of Nurma.

Airways map

The route is built from segments between points to streamline air traffic: if everyone flew randomly, this would greatly complicate the work of dispatchers, since it would be very difficult to predict where and when each of the flying aircraft would end up. And then they all fly away one after another. Comfortable! Dispatchers make sure that planes fly no more than 5 kilometers apart from each other, and if someone is catching up with someone else, they may be asked to fly a little slower (or the other one - a little faster).

What is the secret of the arc?

Why then do they fly in an arc? This is actually an illusion. The route, even along the highways, is quite close to a straight line, and you only see the arc on a flat map, because the Earth is round. The easiest way to verify this is to take a globe and stretch a thread right across its surface between two cities. Remember where it lies, and now try to repeat its route on a flat map.

The flight route from Moscow to Los Angeles only seems like an arc

There is, however, one more nuance regarding transcontinental flights. Four-engine aircraft (Boieng-747, Airbus A340, A380) can fly in a straight line. But more economical twin engines (Boeing 767, 777, Airbus A330, etc.) have to make a detour due to ETOPS (Extended range twin engine operational performance standards) certifications. They must stay no further than a certain flight time from the nearest alternate airfield (usually 180 minutes, but sometimes more - 240 or even 350), and in the event of one engine failure, immediately go there for an emergency landing. It really turns out to be an arc flight.

To increase the “throughput” of the route, separation is used, that is, aircraft are separated in altitude. A specific flight altitude is called echelon, or, in English, Flight Level. The echelons themselves are called - FL330, FL260, etc., the number indicates the altitude in hundreds of feet. That is, FL330 is an altitude of 10058 meters. In Russia, until recently, they used the metric system, so pilots still habitually say: “Our flight will take place at an altitude of ten thousand meters,” but now they have also switched to the international feet.

Navigation display

How do they gain altitude?

“Even” flight levels (300, 320, 340, etc.) are used when flying from east to west, odd flight levels - from west to east. In some countries, trains are divided between the four cardinal directions. The idea is simple: thanks to this, there will always be at least 1000 feet of altitude between planes flying towards each other, that is, more than 300 meters.

But the difference in flight time from east to west and from west to east has nothing to do with flight levels. And to the rotation of the Earth too, because the atmosphere rotates with the planet. It's simple: in the Northern Hemisphere, winds blow more often from west to east, so in one case the wind speed is added to the speed of the aircraft relative to the air (it is conditionally constant), and in the other it is subtracted from it, so the speed relative to the ground is different. And at the flight level the wind can blow at speeds of 100, 150, and even 200 km/h.

Direction of movement of aircraft at flight levels

How does navigation work?

Until recently, pilots were able to navigate, among other things, by the Sun, Moon and stars, and on old planes there were even windows in the upper part of the cockpit for this purpose. The process was quite complicated, so the crews also included a navigator.

In air navigation, ground-based radio beacons are used - radio stations that send a signal on the air at a known frequency from a known point. Frequencies and points are indicated on the maps. By tuning the onboard receiver with a special “circular” antenna to the desired frequency, you can understand in which direction the radio beacon is located from you.

If the beacon is the simplest, non-directional beacon (NDB, non-directional beacon), then nothing more can be learned, but by changing the direction to this beacon at a known speed, you can calculate your coordinates. A more advanced azimuth beacon (VOR, VHF Omni-directional Radio Range) also has circular antennas and therefore can be used to determine the magnetic bearing, that is, to understand what course you are moving relative to this beacon. A rangefinder beacon (DME, Distance Measuring Equipment, not to be confused with Domodedovo Airport), working on the principle of a radar, allows you to determine the distance to it. As a rule, azimuth and ranging beacons (VOR/DME) are installed in pairs.

This is what London and its surroundings look like in the Flight Radar 24 app

FEDERAL AIR TRANSPORT AGENCY

Educational and training center "ChelAvia"

AIR NAVIGATION

Tutorial

Chelyabinsk

PPL(A), Training manual, Air navigation, 2013, Chelyabinsk,

"TC ChelAvia"

This textbook discusses the main issues of the theory and practice of aircraft navigation using geotechnical and radio engineering means, the basics of aviation cartography, and flight navigation elements.

Much attention is paid to the preparation, execution and safety of flights along the routes, as well as the practical use of aircraft navigation aids.

ABBREVIATIONS…………………...………………………….……….….…....4

CHAPTER 1. Basics of air navigation……………………………........5

CHAPTER 2. Aviation cartography……………………….…….…….….….29

CHAPTER 3. Terrestrial magnetism and BC courses……………………….…….……...53

CHAPTER 4. Time. Calculation of time…………………………….……..…….64

CHAPTER 5. Navigation ruler NL-10m……………………….….....……69

CHAPTER 6. Altitude and flight speed……………………………………..…...79

CHAPTER 7. The influence of wind on the flight of an aircraft ………………………….…...….90

CHAPTER 8. Visual orientation……………………………………....…105

CHAPTER 9. Application of goniometric radio navigation systems…….…..131

CHAPTER 10. OSP approach……………………………………..…149

CHAPTER 11. General overview of initial training aircraft navigation equipment………………………………………………………………………………………..…..155

CHAPTER 12. Features of the use of heading instruments and systems for navigation……………………………………………………………….…..…..163

CHAPTER 13. Features of using an automatic radio compass for navigation………………………………………………………………..…...……174

CHAPTER 14. Features of using a satellite navigation system

GNS 430………………………………………………………..………………..176

CHAPTER 15. Ensuring the safety of aircraft navigation….…….…...…..189

BIBLIOGRAPHICAL LIST…………………………….……...…….209

	ABBREVIATIONS
	Airplane seat
	Specified path angle
	Actual track angle
	Drift angle
	Aircraft
	Air traffic services
	civil Aviation
	Aircraft accident
	Flight manual
	Federal Aviation Regulations
	Russian Federation
	Difficult weather conditions
	Air navigation support for flights

CHAPTER 1. BASICS OF AIR NAVIGATION

1.1 Navigation terminology and definitions

The word “air navigation” comes from the Latin “navigatio”, which literally has long meant “navigation”, and in the broadest sense of the word. But quite soon it acquired a narrower meaning: activity (and,

of course, the science that studies this activity) to perform accurate and safe navigation of ships. Determining the location, course and speed of a vessel, preventing it from running aground or reefs, choosing the best route - these and other tasks of marine navigation, which is now more often called navigation, are understandable even to non-specialists.

As people began to move in other environments, air navigation (air navigation) appeared, as well as space, ground and even underground navigation. The main content of any of them is the same - determining the location of an object and the parameters of its movement, controlling its movement along the desired trajectory. Along with the term “air navigation” in

terms have been used at different times, and sometimes continue to be used

"air navigation" and "aircraft navigation".

The terms “air navigation” and “air navigation” are complete synonyms,

since the Greek “aer” means air. But use the word

“air navigation” is clearly preferable. Firstly, in short, secondly,

fully corresponds to similar foreign language terms (English

“airnavigation”, French “navigation aerienne”), and thirdly, this term appeared historically earlier. The term “aircraft navigation,” which refers not only to the driving of airplanes, but also helicopters and other aircraft, apparently originated by analogy with the word “navigation.”

Sometimes the words “radio navigation”, “celestial navigation”, “inertial navigation” and the like are used. These are not separate types of navigation, but the same navigation (air, sea, space), but carried out using technical means of a certain type

(radio engineering, astronomical, etc.). If we talk about air navigation as

science or academic discipline, then these are its sections that consider the use of certain types of navigation equipment.

At the same time, the word “air navigation” is often used in its original, broader meaning, as flights in general. In such, for example,

phrases such as “autumn-winter navigation”, “air navigation information”, “ICAO air navigation commission”, etc. Term

"air navigation", considered in a narrow sense, has two interrelated meanings:

- a certain process or activity of people occurring in reality to achieve a certain goal;

- the science or academic discipline that studies this activity.

The first of these values ​​can be defined as follows.

Air navigation is the control of the aircraft's trajectory carried out by the crew in flight.

By management in general we mean bringing the control object (the one

what is controlled) to the desired position, state, etc. In navigation, an aircraft (AC) is considered as a point moving in space and describing a line - the flight path. The crew in flight controls both the movement of this point, that is, its movement in space, and the trajectory as a whole - its shape, length, etc. The control goals pursued in this case can be different, for example, in civil and military aviation.

If for civil aircraft it is necessary to achieve the closest possible coincidence of the actual trajectory with the given one, then for military aircraft there may not be a given trajectory at all, and the main task will be

for example, accurately reaching a target at a given time.

In general, by “trajectory” in this definition we mean not just a line in space, but a space-time trajectory, that is, a line on which each point corresponds to a certain point in time.

This makes it possible to include such traditional tasks as navigation tasks, such as ensuring access to a given point at the appointed time,

ensuring the flight is on schedule, etc. It would seem that defining the concept

air navigation, it is enough to talk about controlling the aircraft as a point and there is no need to talk about controlling the trajectory. But there are a number of tasks

traditionally navigational, navigational, related specifically to the trajectory,

since the trajectory as a whole has other properties that are not inherent in its individual point. For example, the length of the trajectory and the fuel consumed during the flight depend on the entire trajectory; as mathematicians say, they are its functionals. Therefore, the task of choosing the best trajectory from the point of view of fuel consumption, which is solved by the navigator, is a navigation task.

The flight crew controls the movement of the aircraft. Experts agree that no matter how much airplanes improve, in the foreseeable future people, at least during passenger transportation, will still be in their cabins. But, of course, the crew navigates with extensive use of various technical means. These means remove a significant part of the crew’s workload, and on the most advanced aircraft they leave only the functions of control and decision-making in unforeseen situations to the person.

The place of air navigation in the hierarchy of flight control processes. If you ask the question “who controls the movement of the aircraft?”, it is difficult to get an unambiguous answer. This concept is too multi-level, hierarchical.

Of course, the pilot controls the plane by operating the controls. But he does this in such a way as to maintain the course, speed and altitude given to him by the navigator, who, therefore, also controls the flight. The navigator, in turn, calculated these parameters in accordance with the instructions of the dispatcher

(for example, about reaching a given point at a given altitude), which means that the controller controls the aircraft. But he also sets trajectories not arbitrarily, but in accordance with the traffic patterns established in the given area - routes, corridors,

in echelons. It turns out that the air traffic management authorities that created these schemes are also participants in flight control. This hierarchical ladder of aircraft management can be continued upward. But you can continue down, noticing that the autopilot steering machines actually control the plane...

Where is air navigation in this hierarchy? It is there even when the aircraft can be considered as a point in space, the movement of which must be controlled. And it is quite simple to distinguish this process from adjacent levels of the management hierarchy. As soon as we begin to consider the sun not as a point, but as an object that has dimensions and, therefore, an angular orientation

(course, roll, pitch), piloting begins - angular motion control. And as soon as at least two aircraft appear and, as a result, new tasks arise (separation, prevention of dangerous approaches) -

Air traffic control begins.

Of course, there is no other way to change the flight path except by piloting. The pilot creates a roll and aerodynamic forces force the aircraft to change its trajectory. Navigation is carried out through piloting and these two components of control are inextricably linked. If the crew includes a navigator, then the solution of navigation problems is assigned to him, although

Of course, the aircraft commander (pilot) does not let this process get out of control.

The pilot’s task is to carry out the navigator’s commands to ensure trajectory control. If there is no navigator in the crew, then the pilot performs both navigation and piloting at the same time.

Air navigation requirements. The purpose of a civil aircraft flight is, as a rule, to transport passengers or cargo from one point to another, or to perform a certain type of work (construction and installation, aerial photography,

search and rescue operations, etc.). In achieving these goals, air navigation is usually subject to certain requirements.

1) Air navigation safety. This is the basic requirement. Indeed, there is no point in applying for air navigation any other requirements if there is a threat to the lives of the crew and passengers, if there is no confidence that the aircraft will reach its destination.

2) Accuracy. This requirement is important for civil aircraft, since they fly along specified trajectories. Air navigation accuracy is the degree to which the actual trajectory approaches the given one. Both safety and flight efficiency depend on accuracy. Since the given trajectories build

so that they are safe (do not intersect with obstacles or other trajectories), then the more accurately the aircraft maintains them, the less the risk. On the other hand, given trajectories are usually set to be as short as possible. Consequently, the more accurately the flight is performed, the shorter the trajectory and the shorter the flight time.

3) Economical. The shorter the flight time, the lower, as a rule, the cost of the flight, which includes all associated costs - from personnel wages to the cost of consumed fuel.

4) Regularity. Flights generally must operate on schedule.

A delay in departure or arrival not only brings inconvenience to passengers, but can also lead to significant economic losses. Thus, at airfields with high traffic volumes, a delay in arriving at the initial approach checkpoint may result in the aircraft being sent to a holding area, where it will wait for the time “window” to become available for the approach, wasting fuel.

Main tasks of air navigation. The air navigation process includes the solution of three main tasks:

- formation (selection) of a given trajectory;

- determining the location of the aircraft in space and the parameters of its movement;

- formation of a navigation solution (control actions to guide the aircraft onto a given trajectory).

The formation of a given trajectory begins before the flight, usually long before it, when a network of air routes and given altitudes is established. In this case, this task is attributed not to air navigation itself, but to air navigation support for flights. But the formation of a trajectory can also occur promptly, during flight, when the controller, and sometimes the crew itself, selects which point or which route the aircraft should follow. A given trajectory chosen in one way or another, that is, the trajectory along which it is necessary to fly,

must be both safe and economical, in particular it must not overlap

with ground obstacles and should be as short as possible.

Determining the location of an aircraft in space is one of the main and so important components of navigation, the implementation of which is usually the main effort of the crew, that some identify it with navigation in general, that is, they believe that navigation is only the determination of the location of the aircraft. Indeed, a significant part of on-board and ground-based navigation equipment is designed to determine the coordinates of the aircraft and until now, with the exception of satellite navigation systems, working with it takes up a significant part of the crew’s time. But in addition to the coordinates, it is necessary to know the parameters of the aircraft’s movement, that is, the speed and direction of the aircraft’s movement, and sometimes its acceleration - without this it is impossible to maintain the given trajectory.

Once the location of the aircraft has been determined and it has become clear that it is not on the specified trajectory (and in the vast majority of cases this is the case), it is necessary to determine the magnitude of the deviation and make a navigation decision: how exactly the actual flight path should be changed in order for the aircraft to exit to a given trajectory. This navigation solution may take the form, for example, of a given heading, roll or vertical speed that the navigator transmits to the pilot. The pilot implements them (for example,

turns the aircraft onto a given course) and the aircraft, changing its actual trajectory, brings it closer to the given one. And this sequence of actions is repeated periodically throughout the flight.

On aircraft on which the air navigation process is automated to one degree or another, determining the location of the aircraft, and even placing it on a given trajectory, can be carried out automatically. The navigation decision of the navigator (or pilot, in the absence of a navigator in the crew) is the selected mode of automatic operation of the on-board equipment. There can be several operating modes depending, for example, on what type of technical means are used to determine the coordinates and movement parameters of the aircraft.

Technical navigation aids. Aircraft flights are carried out both at night and above the clouds, when the ground is not visible and visual orientation is impossible. Therefore, determining the location of the aircraft and