RU2095293C1 - Method of accuracy landing of aircraft - Google Patents

Abstract

FIELD: aircraft landing systems. SUBSTANCE: method consists in laying out system of electric conductors along runway and measuring the vertical and horizontal components of electromagnetic field by means of magnetometers fitted on wings and along central axial line of fuselage. EFFECT: enhanced accuracy of landing. 2 dwg

Description

 The invention relates to the field of navigation systems using radiation and measuring electromagnetic waves and can be used to accurately land aircraft on the runway.

 Known methods of landing ships are based on measuring the electromagnetic fields of aerodrome systems, measuring the reflected electromagnetic waves of systems to determine flight altitude and speed of descent, mainly at the final stages of flight during approach and landing (radio altimeter) / 1 /. Radio engineering systems developed on this method and called radiomagnetic are based on the measurement of electromagnetic fields emitted by radio beacons.

 Currently, several radio beacon landing systems are used: domestic SP-50, SP-68, SP-70, SP-75 and international JLS. The JLS system includes three marker, course and glide path beacons. Marker beacons distant (DMRM), middle (SMRM) and near (BMRM) are installed at certain distances from the end of the runway. They emit up coded signals. At the time of the ship’s flight over the lighthouse, these signals are received and measured by the on-board system, and the type of the lighthouse and, therefore, the distance to the start of the runway are determined from the output signals.

 The formation in the space of the course lines and the planning glide path is provided by the radiation fields of the directional radio beacons (CRM), which form an equal-signal zone in the vertical plane, and the sign and deviation from the course line are measured with the help of the course channel receiver. This system allows for the withdrawal of aircraft to the runway.

The low-altitude radio altimeter (RV) is intended to measure the true altitude of an aircraft above the Earth’s surface, the RV is used mainly in the final stages of flight during approach and landing and is practically the only means for determining the aircraft’s position in the vertical plane and calculating the descent rate. The RV-5 type altimeter operates at a frequency of 4300 MHz and the error in measuring low altitudes under favorable meteorological conditions is 10
Thus, the disadvantages of modern methods of landing aircraft on runways, based on the reception and measurement of high-frequency electromagnetic fields, are: the dependence of the measurement error on weather conditions; with a decrease in flight altitude, the measurement error sharply increases, which leads to the need for visual (blind) landing.

 The closest analogue is the landing system, which contains an electric conductor laid along the runway, creating a magnetic field, and on the aircraft there are two magnetic field meters installed at the same distance from its longitudinal axis, according to the testimony of which the aircraft is shifted relative to the axis of the runway / 2 /.

 The advantage of such a system is its simplicity compared to existing ones. However, the measurement of the magnetic field component by two magnetometers does not give a complete picture of the location of the aircraft above the runway without knowing the height of the descent speed, the angle between the longitudinal line of the runway and the aircraft.

 The aim of the invention is to improve the accuracy of landing of the aircraft.

 This goal is achieved by the fact that along the runway they lay a system of electrical conductors that create a magnetic field, measure the vertical and horizontal components of the magnetic field vector with magnetometers mounted on the wings of the aircraft symmetrically with respect to the longitudinal axis of the fuselage. The difference in signals proportional to the vertical component is used to judge the displacement of the vessel relative to the axis of the runway, and the difference between signals proportional to the horizontal component is used to determine the angle between the center lines of the runway and the fuselage. The horizontal component of the magnetic field vector is measured with a magnetometer mounted on the center line of the fuselage, the height of the ship’s flight above the Earth’s surface is judged by the magnitude of its signal, and the aircraft’s descent speed is judged by a change in this signal at a given time interval.

 A system of electrical conductors is laid along the runway and connected to an alternator. The dimensions of the system and its laying along the runway are selected and carried out in such a way that the following conditions are met: uniformity of the horizontal and vertical components of the magnetic field components at the site of the exact landing of the aircraft; the unambiguity of the phase change of any component of the magnetic field when crossing the center line of the runway; a sufficient value of the field intensity of the components. To tie measurements of the flight characteristics of the aircraft to a single point in time, the magnetometer sensors are installed on one line perpendicular to the center line of the fuselage. The fulfillment of these conditions is necessary to reduce the error and unambiguity of measuring the flight altitude, its displacement relative to the center line of the runway, the speed of decline and the course of flight.

 These conditions are laid down in exact equations giving an unambiguous relationship between the magnetic field induction vectors and its components with the coordinates of the aircraft in the upper half-space. Using these equations and the on-board computer allows you to continuously determine the location of the aircraft in the coordinate system associated with the end of the runway and control the descent mode. Moreover, the accuracy of determining the coordinates of the aircraft, taking into account the direction and strength of the wind, is constantly increasing until the moment it touches the runway and is sufficient to fully automate the process of landing the aircraft.

 Marker beacons are currently being installed in the area in front of the runway on its center line. Three different beacons are used at a distance of 100, 1050 and 7400 m from the end of the runway, respectively. When an aircraft flies over an appropriate beacon, its signal is recorded by the airborne marker radio receiver (MCI), which makes it possible to identify the beacon and determine the distance to the end of the runway.

 In our case, instead of beacons, you can use circuits with a current of a certain frequency, laid on the surface of the earth, creating calibrated magnetic fields whose vectors are directed upwards. The receivers of these fields will be the same proposed component magnetic field sensors mounted on an aircraft.

 In FIG. 1 shows the definition of vertical components; in FIG. 2 - determination of horizontal components.

The example of a single-wire line laid along the runway shows the possibility of implementing the method (Fig. 1, Fig. 2). Magnetometers 1, 2 are mounted on the wings of the vessel and the vertical components of the magnetic field B are measured. $\genfrac{}{}{0ex}{}{\text{′}}{\text{b}}$ , B $\genfrac{}{}{0ex}{}{\text{″}}{\text{b}}$ taking into account the phase change. The difference between the signals of the horizontal components of the magnetometers 1, 2 determines the angle between the center axis of the fuselage ab and the axis of the runway a (b) (FIG. 2).

The magnetometer 3 measures the induction of the field of the horizontal component B _g depending on the flight altitude, as well as the speed of descent of the vessel; 4 - runway end face; 5 conductor with current; 6 concentric conventional magnetic field lines with current.

индукция поля вертикальных компонент в районе датчиков магнитометров 1, 2 судят о смещении судна относительно осевой линии ВПП. При B $\genfrac{}{}{0ex}{}{\text{′}}{\text{b}}$ = B $\genfrac{}{}{0ex}{}{\text{″}}{\text{b}}$ и И_в И_г, ΔИ 0, т. е. судно не смещено. По величине сигнала И_з магнитометра 3 определяется высота h полета судна, т. к. она однозначно связана с B_г выражением

где μ_o магнитная постоянная, I сила тока в проводнике.By the difference of the signals ΔU = K (B $\genfrac{}{}{0ex}{}{\text{′}}{\text{b}}$ sinΦ ₁ - B $\genfrac{}{}{0ex}{}{\text{″}}{\text{b}}$ sinΦ ₂ ) where K is the conversion coefficient of the magnetometers V / T 1, 2;

the induction of the field of vertical components in the area of the sensors of magnetometers 1, 2 judge the displacement of the vessel relative to the center line of the runway. At B $\genfrac{}{}{0ex}{}{\text{′}}{\text{b}}$ = B $\genfrac{}{}{0ex}{}{\text{″}}{\text{b}}$ and And _in And _g , Δ AND 0, i.e., the ship is not displaced. The magnitude of the signal And _s magnetometer 3 determines the height h of the flight of the vessel, because it is uniquely associated with B _{g the} expression

where μ _{o is the} magnetic constant, I is the current in the conductor.

Сигналы магнитометров 1, 2, 3 подаются в бортовую измерительно-информационную систему для принятия решений автоматизированной системой посадки судна на ВПП.The rate of descent of the vessel is determined by the change in the signal of the magnetometer 3 according to the expression

The signals of the magnetometers 1, 2, 3 are fed into the on-board measuring and information system for making decisions by the automated system of landing the vessel on the runway.

 The advantage of the proposed method is that the accuracy of landing does not depend on meteorological conditions. With decreasing flight altitude, the accuracy of measuring altitude, descent rate, vessel displacement relative to the center line of the runway, the flight course increases, because the signal-to-noise ratio at the output of the magnetometers increases. Of particular importance is the proposed method in emergency situations, when it is necessary to quickly create conditions for the reliability of landing aircraft (aircraft, helicopters).

Claims (1)

 A method of accurately landing aircraft on the runway (runway), including creating an electromagnetic field by laying a system of electrical conductors along the runway, measuring the components of the magnetic field vector with meters installed symmetrically at some distance from the longitudinal axis of the aircraft, determining the displacement of the vessel relative to the axis of the runway characterized in that the vertical and horizontal components of the magnetic field vector are measured by magnetometers mounted on the wings of the aircraft a, and the difference between the signals proportional to the vertical component is used to judge the displacement of the vessel relative to the runway, and the difference between the signals proportional to the horizontal component and the angle between the center lines of the runway and the fuselage are used to measure the horizontal component of the magnetic field vector by installing a magnetometer on the center axis line the fuselage of the aircraft, by the magnitude of its signal is judged on the height of the flight of the vessel above the surface of the Earth, and by changing this signal in a given time interval is judged on the rate of decline the aircraft.

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