Magnetic heading (MK) is called the angle between the north direction of the magnetic meridian passing through the plane and the longitudinal axis of the plane.

True heading (IR) is called the angle between the north direction of the true meridian passing through the plane and the longitudinal axis of the plane.

Compass heading (QC) is called the angle between the north direction of the compass meridian passing through the plane and the longitudinal axis of the plane.

Line of a given path (LZP)- a straight line between adjacent points of the route.

Specified course angle (ZPU) is called the angle between the north direction of the meridian and the line of the given path.

Drift angle (US) is the angle between the longitudinal axis of the aircraft and the track.

Azimuth (A) landmark is the angle between the north direction of the meridian passing through a given point and the direction to the observed landmark.

Magnetic bearing of a radio station (MPR) is called the angle between the north direction of the magnetic meridian and the direction to the radio station.

Heading angle of the radio station (KUR) called the angle between the longitudinal axis of the aircraft and the direction to the radio station. CSD is counted from the longitudinal axis of the aircraft to the direction to the radio station clockwise from 0 to 360 °.

COURSE - 288 gr.

CHICKEN - 40 gr.

MPR - 328 gr.

AZIMUT - 148 gr.

The magnetic heading for takeoff and landing of the Chuguev airfield is 345 (165) degrees. To find out the true heading, you need to find out the sum of MK and magnetic declination for a given area (+ 8 degrees). That is, IR = 345 + 8 = 353 degrees.

A route is a path from the starting point of the route (IPM) to the final point of the route (MPM). The route, as a rule, includes several turning points (PPP). The straight line between adjacent points of the route is called the line of the specified path (LZP).

So the plane is in the IPM and we need to know where to go next. The direction of travel is determined by a given track angle. However, in the presence of a crosswind component, the aircraft will drift off the line of the specified path, and to maintain the LZP, a correction for the wind must be made. This correction is called the drift angle.

So we figured out how to navigate the plane from one point to another route point.

We maintain the given speed, altitude and ZPU and we will be happy right up to the next PPM. But here's how to determine that we are approaching this very next PPM?

There are several ways to determine the location of an aircraft:

1. Visually, based on landmarks. But, if the landmark is hidden by clouds, or the plane deviates from the LZP at a distance from which the landmarks are indistinguishable, we risk getting lost. Therefore, visual cues serve more to confirm the correctness of our route, than as the main method of navigation.

2. By geographic coordinates (latitude-longitude), you can accurately indicate the location of the aircraft, but to determine the location of the aircraft by geographic coordinates, special equipment is required, which is not available on all aircraft.

3. By azimuth and range to the beacon (radio station), you can determine your location on the route with sufficient accuracy. For this, it is sufficient that the aircraft be equipped with rangefinder equipment and a radio compass. By adjusting the radio navigation equipment on the RSBN, we will be able to control the correct route keeping throughout the flight according to the previously known azimuth and range values ​​at control points.

For example: at control point No. X, the calculated D = 55 A = 70. In fact, we have D = 58 A = 70. So we are going 3 km east of the LZP, and we need to take the appropriate amendment. Or, in the same situation, we have D = 55 A = 90. Therefore, we deviated south of the route and we need to correct the situation.

The purpose of this exercise is for the pilot to learn to determine and maintain his position in range and azimuth, to clearly imagine in which direction and how far he has deviated from the route (the boundaries of the aerobatic zone).

Maintaining a position in the aerobatic zone using RTS.

Using ground visual reference points to determine your location is convenient to a certain extent. For example, focusing on the Pechenezhsky reservoir, you can quite accurately determine the direction to the airfield, but you will hardly be able to visually determine the boundaries of the aerobatic zone with sufficient accuracy. Maintaining your position within the aerobatic zone using the range and azimuth to the RSBN is quite simple.
On the flight map, you have indicated the ranges and azimuths of the boundaries of the aerobatic zone. While completing the task, the pilot must imagine his position relative to the zone boundaries, and accordingly build the next maneuver.

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The average rotor torque is:

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INTRODUCTION

Air navigation in the ISFS began to excite me after the first launch of the flying machine ... I'm lying, after the second, when I moved away from the first. ... Well, not the point. In short, correct flights require knowledge, correct knowledge.

One of the most important problems in ISFS is the impossibility of realizing many "life moments". Therefore, the lectures are a little (and somewhere a lot) simplified.

BASICS OF BASES….

To begin with, I would like to bring you up to date. By the way, here are some very important definitions. In principle, they could have been skipped, but after hearing a couple of anecdotes on the trajectory (see below) I decided to publish it.

- In formation at the shooting range (army). Prapor explains to the AK-47 soldiers:

- This is the butt, this is the trigger, this is the barrel. The bullet flies along an invisible trajectory. Questions.

- (SOLDIER) And what is the invisible trajectory ???

-I'll explain it again. This is the butt, this is the trigger, this is the barrel. The bullet flies along an invisible trajectory. Questions.

- So what is an invisible trajectory ???

- I'll explain again. This is the butt, this is the trigger, this is the barrel. The bullet flies along an invisible trajectory. Questions.

- Comrade Warrant Officer, so what is the invisible trajectory ???

- Well, if the mosquito urinates, then the trajectory is 10 times thinner!

SPATIAL AIRCRAFT PLANE (PMS) Is a point in space at which the center of mass of the aircraft is located at a given time (the aircraft is farther than the aircraft)

PLANE LOCATION Is the projection of the PMS onto the earth's surface.

WAY LINE Is the projection of the flight path onto the earth's surface. Distinguish between the line of the given path of the LZP and the line of the actual path of the LFP. LZP is the line along which the aircraft should move, and LFP is the line along which the aircraft is actually moving or moving. From this it is clear that LFP should coincide with LAP.

FLIGHT ROUTE - this is one or several LZP passing through navigation points (landmarks, radio beacons).

The route is set by the Way Angle (PP) and the orthodromic distance between the turning points of the route (PPM).

TRAVEL ANGLE (PU) Is the angle between the direction taken as the origin and the track line.

MERIDIAN (conventionally) - the direction from which the PU is counted.

PU is counted clockwise from 0 to 360 degrees.

Distinguish between ZPU and FPU (Specified track angle and actual track angle - as with a track line!)

ORTHODROMY - a great circle arc passing through 2 given points lying on the earth's surface and lying in a plane passing through the center of the globe. - Cool definition? For simplicity - orthodrome - the shortest distance between 2 points. Moreover, this is not a straight line. This is an arc, or rather, a part of it. For example, all meridians are orthodromic lines. Equator is an orthodromic line. If the measured distance is not more than 800 km, then the orthodrome is considered a straight line for simplicity and is measured on the map. If the distance is greater, then the formulas for calculating on an ellipsoid or a sphere are used (geometric bodies are such). Well, this is already superfluous ... Formulas are cool and three-story. For now, we will not consider them. Or maybe we won't (it's hard to imagine a simmer who counts by such formulas!)

IPM - Starting point of the route

KPM - Destination of the route

A LITTLE STEP. DIRECTIONS …

Depending on where the meridian is located, there are:

PU initial

PU medium

PU final

In aviation, the initial PU is mainly used.

There are several accepted meridians relative to which PU is measured:

TRUE (geographical) - depicted on maps, globe. Direction to the geographic pole of the earth.

MAGNETIC - direction to the earth's magnetic pole.

SUPPORT - any convenient direction.

EXPLANATION:

As you know, the Earth is a magnet. It is this property that determines the presence of magnetic meridians. Unfortunately, or perhaps fortunately, the magnetic and geographic poles do not coincide. Moreover, they are completely opposite !!! In fact, from a physics standpoint, north is south and south is north. The arrow is rotated by the magnetic lines of force. And, therefore, north indicates south. This is a school physics course, friends! (You can read it in the book) It just happened that the directions were distributed first, and then they found out - they were distributed incorrectly. For simplicity, so as not to reshuffle the usual ideas about directions, they took everything as it is at the moment. North - north, south-south. It should be borne in mind that an ordinary compass indicates a MAGNETIC direction.

We will consider the reference meridian later, when we are closely acquainted with the orthodromy, gyro-SEMI-compasses, etc.

Depending on the selected meridian, magnetic PU (MPU), true PU (IPU), orthodromic PU (OPU - from the reference meridian) are distinguished.

They, in turn, are divided into actual and specified (ZPU and FPU; ZMPU, FMPU; FIPU, ZIPU; OFPU; OZPU). Naturally, the given is the necessary, the actual is the current. Therefore, it is necessary that the ZPU and FPU coincide!

SOME TERMS AND CONDITIONS AND AMENDMENTS:

See - the north direction of the magnetic meridian.

Si - the north direction of the true meridian

So - the northern direction of the reference meridian

In navigation charts, the initial ZMPU is indicated, i.e. counted from the CM passing through the PPM.

D А - azimuth correction - the angle between Co and Cu.

D M - magnetic declination - the angle between Cu and C. It arises due to the mismatch of geographic and magnetic poles. Magnetic declination is determined using special instruments.

D Mu - conditional magnetic declination, the angle between Co and Cm.

All these corrections are counted from -180 to +180 degrees, from the north direction of the corresponding meridian - to the left with a minus sign, to the right - with a plus sign. In this case, before the numerical value of the correction NECESSARILY put a sign - or +.

The lines of equal magnetic declination plotted on the maps are called ISOGONS.

BASIC ANGLE CONVERSION FORMULAS:

D Mu = D A + D M

IPU = MPU + D M

IPU = OPU- D A

MPU = IPU- D M

MPU = OPU- D Mu

OPU = MPU + D Mu

OPU = IPU + D A

The only thing is that there is no KK - compass course - more on that later.

PRACTICE

TASK # 1

MPU = 180

IPU = 186

D M-?

Let's solve it together.

So, MPU = IPU-D M

Applying the transfer rules, from mathematics, we have:

D M = IPU-MPU

Substituting the values ​​in the final formula, we get D M = - 4

ANSWER: D M = - 4.

PROBLEM No. 2

OPU = 67

D Mu = + 4

D A = - 5

MPU-?

IPU-?

First, we get D M:

D Mu. = D A + D M

respectively,

D M = D Mu - D A

We get D M = +9

Then, LPU.

MPU = OPU - D Mu

MPU = 63

IPU can be found in two ways.

IPU = MPU + D M

IPU = OPU - D A

Take the most convenient method.

IPU = 72

ANSWER:

IPU = 72

MPU = 63

For a better memorization of the formulas for recalculating angles, invent tasks of varying complexity yourself. That's not difficult. You can also repeat them periodically to yourself. In short, systematic exercise. These formulas are some of the most basic!

COURSES

WELL -it is the angle in the horizontal plane between the north direction of the meridian that passes through the aircraft taken as the origin and the projection of the longitudinal axis of the aircraft onto the horizontal plane. Also a cool definition.

It is counted clockwise from 0 to 360 degrees.

Depending on the selected meridian, there are:

IR - True Heading

MK - magnetic heading

OK - orthodromic course

The course can be changed by the aircraft roll. Well, what is a roll, I think there is no need to explain! ;-)

Conversion formulas look the same as for angles. Only there are no actual and assigned courses.

THE AFTERWORD

And so, in the first lecture, we examined the basic spatial definitions, angles, courses, their recalculation. We solved a couple of problems.

All questions that you have during the study of the material (and you have them, for sure) send me to the soap.

In the next lecture, we'll look at coordinate systems and horizontal maneuvering elements!

Happy calculations!

Soap: A .Zaharov @Rambler .ru

First of all, you need to decide what the wind is. Wind is the movement of air masses from one point to another. As you know, any aircraft moves inside the air mass. But what if the air mass in which the flight takes place also moves relative to the ground? In addition to moving at its own speed relative to the air mass, the plane will also move with the speed of this air mass. Considering that the wind speed at altitudes can reach values ​​of more than 200-300 km / h, it becomes obvious that taking into account the wind in flight is extremely important. It is easy to calculate that if, with such a wind (let us assume strictly sideways), fly along the route for one hour and do not take into account the wind, then in an hour the plane will be 200-300 km away from the route. If this is a head wind, and the crew does not take it into account at the stage of preparation for the flight, there may simply not be enough fuel to reach the destination aerodrome.

True and ground speed.

When taking into account the effect of wind on flight, two types of speeds are distinguished: true airspeed(denoted by V and or in English TAS - true airspeed) and (denoted by W or in English GS - ground speed).

True Airspeed Is the speed of the aircraft in relation to the air mass in which it is flown.

Ground speed- the speed of the aircraft relative to the ground.

Remember that wind does not affect true airspeed. The effect of the wind affects only ground speed.

Course and track angle.

By analogy with the speed, when taking into account the wind, two directions of the aircraft flight are distinguished: course (HDG - heading) and track angle(denoted by PU, in English TRK - track).

Well Is the angle between the north direction of the meridian taken as the origin and the longitudinal axis of the aircraft.

Track angle Is the angle between the north direction of the meridian taken as the origin and the track line. Distinguish actual track angle (FPU) and given track angle (ZPU).

As for the counting of directions, several meridians of the origin are used in navigation: true, magnetic, reference. When solving problems related to wind accounting, provided that all values ​​are reduced to the same meridian, it does not matter which directions are applied, true or magnetic.

Direction of the wind.

In air navigation, two types of wind are distinguished: navigational(HB) and meteorological, their directions differ by 180 degrees and by the magnetic declination. The fact is that basically in aviation it is customary to perform all calculations from the magnetic meridian, while in meteorology it is much more convenient to use the true direction of the meridian of the origin.

Nautical wind- the angle between the north direction of the meridian, taken as the origin and the direction where the wind is blowing.

Meteorological wind- the angle between the north direction of the meridian taken as the origin and the direction from which the wind is blowing.

The navigational wind is used exclusively as an auxiliary value in the calculations. The meteorological direction of the wind is the value to which each of us is accustomed. Southwest wind means that the wind is blowing from the Southwest, or if we recalculate it in degrees, we get the direction of 225 degrees, it is in this form that the value of the wind direction in aviation is used.

Navigational speed triangle.

As you know, velocity is a vector quantity. The vectors of airspeed, wind, and ground speed form the so-called speed navigation triangle (NTS)- the basis of the basics of air navigation. By applying general rules geometry and trigonometry can calculate all magnitudes and angles, knowing the direction and magnitude of two vectors.

As you can see from the figure, the plane's flight follows a certain trajectory - lines of a given path, which corresponds to the ground speed vector, but the longitudinal axis of the aircraft is turned to the wind to compensate for drift, as we remember, the longitudinal axis corresponds to the air speed vector.

Thus, we got the angle to which we need to turn into the wind so that the flight passes along the track, this is drift angle - US(in English WCA - wind correction angle or drift angle).

In other words, it is the angle between the air and ground speed vectors. The drift angle is always counted from the airspeed vector clockwise (as in our case) with a plus sign, counterclockwise - with a minus sign.

To calculate the wind-corrected flight path, it is necessary to subtract the drift angle with its sign from the track angle.

Calculation of the drift angle and ground speed.

To calculate the drift angle and ground speed, it is necessary to calculate an auxiliary value, which is called wind angle (SW)- the angle between the ground speed vector and the wind vector, that is, this is the wind direction with reference to the direction of movement of the aircraft.

Recall that the navigational wind (NW) differs from the meteorological wind by 180 degrees and, as a rule, by the magnitude of the magnetic declination.

Using the theorem of sines, we also obtain the formula for the drift angle:

This formula can be easily simplified by expressing angular quantities in radians:

U- wind speed, V and- true airspeed. For a correct calculation, both of these values ​​must be reduced to the same unit of measurement, for example, knots or meters per second. In practice, instead of a constant value 57,3 apply 60 , which gives minimal error, but makes it much easier to calculate the drift angle in your head.

The ground speed formula is derived by projecting the airspeed and wind vectors on the corresponding axis and looks like this:

For small values ​​of the drift angle, you can use a simplified formula:

If in Russia it is customary to calculate the drift angle with a plus or minus sign, then in the west pilots are taught a little differently: the angle itself is calculated as a modular value, to which the letters R or L are added, R means that the axis of the aircraft must be turned against the wind to the right , that is, add the drift angle to the track angle, and L - vice versa to the left, that is, the drift angle is subtracted from the track angle. In addition, the calculation of the drift angle and ground speed is mainly carried out not according to the formulas, but with the help of the mechanical computer E6B and its analogues.

We count in the mind.

There is a simple algorithm for calculating the drift angle in your head. First of all, you need to calculate maximum drift angle at a given wind. As you might guess, it will be maximal with a crosswind, that is, with a wind angle of 90 degrees, and since the sine of 90 degrees is equal to one, we eliminate this part of the formula and get:

Having estimated the maximum value of the drift angle, it needs to be corrected for the direction, which is easily done in the mind, if you know the values ​​of the sines of the main angles:

The sign is determined based on the direction of the wind, if the wind blows to the starboard side, then minus, if to the left, then plus.

Knowing the cosines of the main angles, it is also easy to calculate the longitudinal wind component in your head, which in turn will allow you to calculate the ground speed.

As an example, let's calculate in our head the drift angle and ground speed for the Boeing 737 during the landing approach, having the following data:

Airspeed on approach 140 knots

Landing track angle 90˚

Wind 120˚, 30 knots

Determine the maximum drift angle: 12˚, adjust to the wind direction. The wind is head-on to the starboard side under 30˚, so the drift angle is minus 6˚, that is, it is necessary to turn to the right against the wind by 6˚. Next, we calculate the headwind component: 26 knots. Subtracting it from the airspeed, we get the ground speed on the glide path of 114 knots.

The choice of the reference system for the flight path angles and the aircraft heading is determined by the operational data of the aircraft and its navigation equipment.

The conditions for using course instruments on an airplane can be divided into three groups:

1. Flights with small limits of variation of magnetic latitudes on airplanes equipped with magnetic or gyromagnetic compasses.

2. Flights with significant changes in magnetic latitudes on airplanes equipped with magnetic compasses, gyro-compasses or medium-precision heading systems, without automatic measurement of drift angle, ground speed and dead reckoning.

3. Flights over any distance on airplanes equipped with precise heading systems and instruments for automatic measurement of drift angle, ground speed and dead reckoning.

For the first group of conditions, a magnetic loxodromic reference system of flight path angles and aircraft heading is selected. In this case, the length of each loxodromic track segment is taken such that the magnetic track angle at its starting point differs from the track angle of the end point by no more than 2 ° for a segment length of up to 300 km, i.e.

In this case, the average magnetic track angle of the segment differs from the extreme ones by no more than 1 °, and the maximum deviation of the loxodromic track line from the orthodromic one does not exceed the value that is, the loxodromic line coincides with the orthodromic one.

If the initial and final track angles of the segment differ by less than 2 °, then the length of the loxodromic track segment can be increased when flying in the meridian direction or in any direction in equatorial latitudes with small changes in Dm.

The magnetic loxodromic track angle in the practice of air navigation is usually called the magnetic track angle (MPA).

MPU is measured relative to the magnetic meridian of the midpoint of the segment of the path:

For the second group of conditions, an orthodromic frame of reference for flight path angles and aircraft headings relative to the reference meridians or the initial meridians of the path segments is selected. In this case, the orthodromic flight angle (OPA) is considered equal to the true track angle of the segment at its starting point or at the point of intersection of the continuation of the segment with the reference meridian.

When flying over the reference meridians or the starting points of the path segments, the gyrocompass or course system set according to the indications of the true heading of the aircraft. For example, the heading system is switched to the MC mode with the setting (on the declination scale) of the magnetic declination at the MC point or to the astronomical correction mode. After agreeing (working off the true course), the system is transferred to the GPC mode.

If you need to check the accuracy of the readings of the orthodromic

If these conditions are not met, then the readings are OK. an amendment is introduced that aligns the left side of the equation with the right.

The deviation of the magnetic compass for the third group of conditions is taken into account according to the rules adopted for the second group.

Considering the high accuracy of directional devices for both the third and the second groups, depending on the specific flight conditions, it is possible to use orthodromic readout of track angles from the magnetic reference meridians.