RU69018U1 - AIRCRAFT LANDING SYSTEM - Google Patents

Abstract

The utility model relates to aircraft, in particular, to aircraft landing systems that use laser emitters, and can be used to improve pilot orientation when piloting an aircraft during an approach approach and landing in limited visibility (at dusk, at night and in difficult weather conditions). The objective of the proposed solution is to create a reliable laser landing system that increases the level of safety during aircraft landing, characterized by an increased service life, minimal power consumption and small dimensions. The technical result is improved visibility of laser beams in airspace and a combination that creates a symbol by which the pilot determines the position of the aircraft relative to the landing path and touchdown point, especially in difficult weather conditions, increasing the efficiency of the system in terms of ensuring reproducibility of aircraft landing accuracy due to optimal locations of laser emitters and the laser beams generated by them. The problem is solved in that in the aircraft landing system containing at least three laser emitters installed near the runway from the side of the aircraft approach, two of which - glide paths - are located at the edges of the strip and are designed to form rays defining the glide path plane, and the third - course - located on the continuation of the axial line of the strip, and is designed to form a beam that determines the landing course according to the technical solution as laser emitters Lei use semiconductor laser emitters, while at least the directional emitter is configured to change the direction of the formed beam in the vertical and horizontal planes, the glide path emitters are installed at a distance d from the beginning of the strip, and the directional emitter is installed with the possibility of forming a beam at an angle α relative to horizontal plane, while the value of d and α is determined from the following relations:

d = Δh / tgφ,

β <α <φ,

where Δh is the specified value of the permissible vertical position error of the aircraft at the point of the long-distance drive during landing, φ is the specified angle of inclination of the glide path, β is the angle of free passage of the beam over the terrain. Glide path emitters can also be configured to change the direction of the formed beam in the vertical and horizontal planes. With a continuous radiation intensity of glide path emitters, the radiation intensity of the directional emitter can be modulated with a frequency selected from the condition for the possibility of visual identification of a beam with a modulated intensity. With a continuous radiation intensity of the directional emitter, the radiation intensity of the glide path emitters can be modulated with a frequency selected from the condition for the possibility of visual identification of rays with modulated intensity. The radiation intensity of the glide path emitters can be modulated with a frequency different from the frequency of the modulation of the radiation intensity of the directional emitter. In this case, the difference between the frequencies of modulation of the radiation intensity of the directional and glide path emitters is determined by the possibility of visual observation of these differences. As laser emitters in the landing system, laser emitters can be used that emit light in the invisible - infrared region of the spectrum, due to which full blackout can be ensured. At the same time, the aircraft may land using night vision devices. The radiation intensity of laser emitters can be adjusted, if necessary, depending on atmospheric conditions in the airspace around the aerodrome.

Description

The utility model relates to aircraft, in particular, to aircraft landing systems that use laser emitters, and can be used to improve pilot orientation when piloting an aircraft during an approach approach and landing in limited visibility (at dusk, at night and in difficult weather conditions).

Among the aircraft landing systems that use laser emitters, and the operation of which does not require equipping the aircraft with any additional equipment, the landing system is known (US Patent No. 6320516, IPC: G08G 5/00), which includes two laser sources, the light of which from a gas laser is fed through an optical fiber and which are installed at the beginning of the runway (runway) along its edges. Rays from these sources are directed at a small angle to the center line of the runway, and in a plane perpendicular to the plane of the runway, the rays are scanned in space, forming two triangular light walls that indicate the corridor for the movement of the aircraft. Moreover, the lower position of the beam in the scanning plane indicates the correct path of descent of the aircraft. In addition, the light from the second gas laser, propagating through the optical fiber, creates at the beginning of the runway a certain network of lights on its plane, which also includes the center line of the runway. The disadvantages of this system, of course, include the lack of the ability for the pilot of the aircraft to navigate in space in azimuth, because the light from the grid of lights on the runway designating the center line will not be visible in conditions of limited visibility, as well as the lights of a conventional light-signal system. In addition, being guided by the lower position of the side laser beams when scanning them, the pilot of the aircraft is not able to uniquely determine the position of the aircraft relative to the plane of the glide path, as proposed in this invention. In addition, the system itself is quite complex as it requires the use of scanning devices for laser emitters.

Aircraft landing system is also known (USSR Author's Certificate No. 1828036, IPC: B64F 1/18), which contains three laser emitters installed at the beginning of the runway (one in the center and two at the edges) and four laser emitters mounted on the side borders of the runway symmetrically to its longitudinal axis. Blocks of laser emitters create beams of laser beams located in planes perpendicular to the surface of the runway and parallel to it

axis, and angled to each other. When the aircraft enters the landing area and intersects the laser beams, the blocks of laser emitters must rotate around the vertical and horizontal axes so that the laser beams come closer to the laser beams generated by three laser emitters. The obvious disadvantage of this system is its complexity, due, firstly, to the use of a large number of laser emitters, and secondly, the need to adjust the position of the laser emitter units during the landing of the aircraft.

Closest to the claimed is the laser landing system of aircraft "Glissada" (Zuev V.E., Fadeev V.Ya. Laser navigation devices. - M .: Radio and communications, 1987), which includes several laser emitters, including course glide path, marker and marking the side boundaries of the runway. The system uses the principle of projective geometry and the phenomenon of laser radiation scattering in the atmosphere, due to which the pilot visually perceives a combination of rays in the form of a symbol that determines the position of the aircraft relative to the landing trajectory and landing point. In this case, the directional laser emitter is installed on the runway center line in front of the runway end, and the glide path laser emitters are installed on the outside of the runway side boundaries closer to the runway end. As laser emitters, HE-NE lasers are used - lasers or continuous krypton lasers. Rays of laser emitters are directed towards the movement of the landing plane. The angle of inclination of the rays of the glide path laser emitters relative to the horizontal plane of the runway is 2 degrees 40 minutes.

The disadvantage of this landing system is the use of gas lasers as laser emitters, which have insufficient reliability, short MTBF, large dimensions and power consumption. In addition, the use of gas lasers emitting light in the visible spectrum does not allow the creation of reliable means of blackout. In addition, in the description of the system, the location parameters of the laser emitters relative to the runway are not defined, the parameters of the angles of inclination of the laser emitters relative to the horizontal plane of the runway and relative to the center line of the runway are not defined.

The objective of the proposed solution is to create a reliable laser landing system that increases the level of safety during aircraft landing, characterized by an increased service life, minimal power consumption and small dimensions.

The technical result is improved visibility of laser beams in airspace and a combination that creates a symbol by which the pilot determines the position of the aircraft relative to the landing path and touchdown point, especially in difficult weather conditions, increasing the efficiency of the system in terms of ensuring reproducibility of aircraft landing accuracy due to optimal locations of laser emitters and the laser beams generated by them.

The problem is solved in that in the aircraft landing system containing at least three laser emitters installed near the runway from the side of the aircraft approach, two of which - glide paths - are located at the edges of the strip and are designed to form rays defining the glide path plane, and the third - course - located on the continuation of the axial line of the strip, and is designed to form a beam that determines the landing course according to the technical solution as laser emitters Lei use semiconductor laser emitters, while at least the directional emitter is configured to change the direction of the formed beam in the vertical and horizontal planes, the glide path emitters are installed at a distance d from the beginning of the strip, and the directional emitter is installed with the possibility of forming a beam at an angle α relative to horizontal plane

The value of d and α is determined from the following relationships:

d = Δh / tgφ,

β <α <φ,

where Δh is the specified value of the permissible error of the vertical position of the aircraft at the point of distant drive during landing,

φ - a given angle of inclination of the plane of the glide path,

β is the angle of free passage of the beam over the roughness of the terrain.

Glide path emitters can also be configured to change the direction of the formed beam in the vertical and horizontal planes.

With a continuous radiation intensity of glide path emitters, the radiation intensity of the directional emitter can be modulated with a frequency selected from the condition for the possibility of visual identification of a beam with a modulated intensity. With a continuous radiation intensity of the directional emitter, the radiation intensity of the glide path emitters can be modulated with a frequency

selected from the condition for the possibility of visual identification of rays with modulated intensity.

The radiation intensity of the glide path emitters can be modulated with a frequency different from the frequency of the modulation of the radiation intensity of the directional emitter. In this case, the difference between the frequencies of modulation of the radiation intensity of the directional and glide path emitters is determined by the possibility of visual observation of these differences.

As laser emitters in the landing system, laser emitters can be used that emit light in the invisible - infrared region of the spectrum, due to which full blackout can be ensured. At the same time, the aircraft may land using night vision devices.

The radiation intensity of laser emitters can be adjusted, if necessary, depending on atmospheric conditions in the airspace around the aerodrome.

The utility model is illustrated by drawings, in which Fig. 1 is a general top view of a runway, Fig. 2 is a general view of a runway at an angle from the side, Fig. 3 is a general side view of a runway, and Fig. 4 is a diagram of the arrangement of laser rays observed from the landing plane at different positions relative to the landing trajectory.

The positions in the drawings indicate: 1 - runway, 2 - left glide path emitter, 3 - right glide path emitter, 4 - directional emitter, 5 - airplane, 6 - laser beam of the left glide path emitter, 7 - laser beam of the right glide path emitter, 8 - laser beam course glide path emitter.

The letters and symbols in the drawings denote: d is the distance at which the glide path emitters are located relative to the runway end face, φ is the glide path angle, α is the angle of inclination of the laser beam of the directional emitter, β is the angle of free passage of the beam over uneven terrain, Δh is the value of the permissible position error aircraft vertically at the point of distant drive during landing.

Laser emitters 2, 3 and 4, constituting the aircraft landing system, are located at the beginning of the runway in accordance with Figure 1, Figure 2 and Figure 3. Glide path laser emitters 2 and 3 are installed at the edges outside the runway, as close to its lateral borders as possible, as other equipment located near the runway allows. The distance from the end of the runway to the installation location of glidepath laser emitters d is determined by the specified value of the allowable error of the position of the aircraft

vertically at the point of the long-distance drive during landing (Figure 3). This is explained as follows. Laser beams 6 and 7 of emitters 2 and 3 are directed parallel to the axial plane of the runway toward the landing plane 5 at an angle of glide path φ relative to the horizontal plane of the runway (Figure 3). The value of this angle is set for each aerodrome, depending on the terrain. According to the laws of projective geometry, the pilot observes rays 6 and 7 in the form of luminous segments emanating from the edges of the runway in opposite directions from the runway (Figure 4). If the plane is in the plane of the glide path, then the visible segments of the rays 6 and 7 will be perpendicular to the center line of the runway (Figure 4, 2, 4 and 5). It is the perpendicularity of the segments of the rays 6 and 7 of the center line of the runway that means the exact position of the aircraft in the plane of the glide path. If we take into account that the glide path plane intersects with the runway at the point where the aircraft landing gear touches the runway (i.e., at its beginning), it becomes clear that moving the installation site of the glide path emitters a distance d from the start of the runway conditionally raises the glide path plane relative to the runway by the value Δh = d * tgφ (Figure 3). Therefore, taking into account the accepted vertical position tolerances at the point of long-distance drive during landing, the distance value d must satisfy the condition d <Δh / tgφ. This circumstance must be taken into account if, to ensure a safe landing of the aircraft in conditions of limited visibility, so that the pilot can see segments of rays 6 and 7 as long as possible, glide path emitters are placed at the maximum possible distance from the start of the runway.

The directional laser emitter 4 is installed on the outer side of the end edge of the runway as close to this edge as possible, as other equipment located near the runway allows (Figure 1, Figure 2 and Figure 3). Beam 8 of the directional emitter 4 is directed towards the landing plane 5 strictly in the vertical plane passing through the center line of the runway and at an angle α relative to the horizontal plane of the runway (Figure 3). The angle α is determined by the ratio β <α <φ, where the angle β is the angle of free passage of the beam over the roughness of the terrain (Figure 3). According to the laws of projective geometry, the pilot of the landing plane sees beam 8 in the form of a luminous segment, which will be a continuation of the center line of the runway if the plane moves strictly along the course (Fig. 4, pos. 1, 2 and 3).

Landing an aircraft using the proposed laser landing system is as follows.

As the aircraft approaches the point of distant drive, the pilot, as mentioned above, observes the laser beams 6, 7 and 8 in the form of luminous segments emanating from the points

installation of laser emitters (Figure 4). These segments serve as convenient guidelines for the pilot to determine the position of the aircraft, both relative to the landing course, and relative to the plane of the glide path. With the correct approach to the point of the long-range drive using standard radio equipment, it is not difficult for the pilot to recognize glide paths 6 and 7 and course 8. If the pilot for some reason makes a big mistake in observing the approach path to the point of the long-distance drive, then for the correct pilot identification of the right and left glide path and course beam, the intensity of their radiation can be modulated with a frequency easily perceived and fixed by the human eye (several Hz). Different options are possible here. For example, the intensity of the directional beam can be intermittent, and the intensity of the glide path rays can be constant, or vice versa. The intensity of all three beams can be intermittent, but the frequency of the modulation of the intensity of the directional beam should differ from the frequency of the modulation of the intensity of the glide path so that it is easily fixed by the eye of the pilot. With the correct position of the aircraft on the trajectory during landing after passing through the long-distance drive point, the pilot sees the directional beam 8 as a continuation of the runway center line, and the segments of glide path rays 6 and 7 observed by him should be perpendicular to the center line of the runway, i.e. segment directional beam 8, and make one line (Figure 4, 2). Any deviations of the aircraft from the correct path will cause a change in the position of the segments of the rays relative to each other. So if the plane follows the course, but is above the plane of the glide path, then the ends of the segments of the glide path rays will fall down (Figure 4, position 1), if below the plane of the glide path, then rise up (Figure 4, position 3). If the plane moves in the plane of the glide path, but to the right of the right course, then the end of the segment of the directional beam will move to the left (Figure 4, 4), if to the left of the right course, then to the right (Figure 4, 5). Obviously, mixed situations are possible when the plane is not on the glide path plane and off course. In this case, the arrangement of the rays will correspond to a combination of any two positions shown in FIG. 4. Thus, the task of the pilot when landing the aircraft according to the claimed landing system is to maintain the aircraft on such a trajectory, at each point of which the segments of glide path rays 6 and 7 observed by it should be a straight line, and the segment of the directional beam 8 should be perpendicular to this line. The energy consumption of the entire system was not more than 800 W, the dimensions of one laser emitter were 200 × 400 × 600 mm.

A significant advantage of the claimed system is the high sensitivity of the response of the position of the visible segments of the rays relative to each other (Figure 4) to changes in the position of the aircraft relative to a given trajectory of decline. This determines the high accuracy of landing (+/- 0.5 m), which provides the inventive system.

In accordance with the claimed solution, a laser landing system was made and installed at the airport, containing three emitters based on semiconductor lasers that generate light at a wavelength of 635 nm. The directional emitter was installed at a distance of 60 m from the end of the runway and its beam was directed at an angle of 1 degree 8 minutes relative to the horizontal plane of the runway. Glide path emitters were installed at a distance of 3 m from the side edge of the runway and at a distance of 300 m from the directional emitter. Rays of glide path emitters were directed at an angle of glide path (2 degrees 50 minutes) relative to the horizontal plane of the runway. 9 approaches were made on the Yak-40 airplane in the dark, several of which were extinguished by high-intensity extinguished lights and one by the runway extinguished lights. The range of visibility of the rays in normal weather at night was more than 10 km (the distance of the point of distant drive was 4 km, Δh = + / - 20 m). Landing accuracy for such a system was +/- 0.5 m.

Thus, the claimed system allows for high precision landing of the aircraft in conditions of limited visibility and even when the standard lighting equipment of the airfield is turned off.

Claims (7)

1. Aircraft landing system, containing at least three laser emitters installed near the runway from the side of the aircraft’s approach, two of which - glide paths - are located at the edges of the strip and are designed to form rays defining the glide path plane, and the third - course - located on the continuation of the axial line of the strip, and is designed to form a beam that determines the course of landing, characterized in that semiconductor laser emitters are used as laser emitters and wherein at least ESP emitter is adapted to change the direction of the beam formed in the vertical and horizontal planes, glide path Emitters installed at a distance d from the beginning of the strip, and ESP emitter mounted to the beam forming an angle α relative to the horizontal plane, the value of d and α is determined from the following relations: d = Δh / tgφ, β <α <φ, where Δh is the specified value of the permissible error of the vertical position of the aircraft at the point of distant drive during landing, φ - a given angle of inclination of the plane of the glide path, β is the angle of free passage of the beam over the roughness of the terrain. 2. The landing system according to claim 1, characterized in that the glide path emitters are configured to change the direction of the formed beam in the vertical and horizontal planes. 3. The landing system according to claim 1, characterized in that the glide path emitters are configured to produce rays with continuous intensity, and course - with the possibility of forming a beam with modulated intensity, while the pulse repetition rate is selected from the condition that they can be visually identified. 4. The landing system according to claim 1, characterized in that the directional emitter is made with the possibility of forming a beam with continuous intensity, and glide paths with the possibility of forming rays with modulated intensity, while the pulse repetition rate is selected from the condition that they can be visually identified. 5. The landing system according to claim 1, characterized in that the laser emitters are configured to generate rays with modulated intensity, while the modulation frequencies of the glide path and directional emitters are selected different with the possibility of visual observation of these differences. 6. The laser landing system according to claim 1, characterized in that as laser emitters, to ensure full blackout, emitters are selected that emit light in the invisible - infrared region of the spectrum. 7. The laser landing system according to claim 1, characterized in that the laser emitters are configured to control the radiation power depending on atmospheric conditions.