EP0727638B1 - Method and apparatus for fighting against helicopters operating under cover - Google Patents

Description

The invention relates to a method and an apparatus with the aid of which operating under cover, appearing briefly and then covering again using enemy helicopters even after losing line of sight using a selectively designed on helicopter type recognition electro-optical seeker head can be effectively combated.

Such devices are known in different embodiments. As The patent specification DE 37 33 681 C1 can be mentioned as an example of this. In the Known device for helicopter detection is a so-called infrared seeker head used. The search head essentially consists of an entry optic in their Focal plane infrared-sensitive detector elements arranged in a rectangular matrix are. Each detector element can be read out individually, the resulting one Signal to be examined according to amplitude and frequency behavior.

The observation axis of the seeker head is oriented vertically downwards, whereby it can be assumed that enemy helicopters, shadowing of the terrain using moving close to the ground. The search head is designed so that he helicopter due to its field of view design and its height above ground based on their characteristic radiation modulated by the rotor blade movement should be able to reliably recognize in a defined search area.

The design of the seeker head on the vertical direction of observation limits the operational performance of a defense missile equipped with this sensor considerably, especially if it is "shoulder lockable" got to. The criteria for shoulder lockability are light weight (typically 12 kg), easy handling, high reliability and a favorable cost / benefit ratio.

In conjunction with a missile, it can be oriented vertically downwards Sensors are used as follows. The observing shooter discovers an enemy Helicopter. He estimates the distance to the target and gives this value into the launch device of the missile. Since the sensor image field is limited, The success of the control measure depends on the reliability of this estimate crucially. It must also be ensured that the Predefined search ranges overlap. The missile is launched. Moved according to the distance data and the specified sensor image field the missile is in a predetermined trajectory and then at a height of typically to be braked 800 - 1200 m by a rear parachute. The missile longitudinal axis is oriented vertically after completion of the braking process, the target seeker looks down, the search phase begins. The falling speed must be adjusted by the parachute to the performance of the signal evaluation process become. If the target is detected, the parachute is disconnected. The remaining one Part of the missile containing the warhead must now proceed from the low falling speed, so far accelerated that the target itself can be reliably fought at maximum escape speed.

• Falsche Entfernungsschätzung führt zu Fehlschuß, was nur durch einen zusätzlich eingesetzten Laserentfernungsmesser vermeidbar wäre.
• Die Suchphase erfolgt bei geringer Flugkörpergeschwindigkeit. In der daraus resultierenden Zeit kann das Ziel eine zusätzliche Distanz zurücklegen, deren Überwindung erhöhte Anforderungen an die Zielverfolgungsgeschwindigkeit des Flugkörpers stellt.
• Aufgrund der ungünstigen Energiebilanz durch zusätzliche Brems- und Beschleunigungsmanöver erhöhter Treibstoffbedarf, und daraus resultierend Gewichtszunahme, ungünstiges Kosten-/Nutzenverhältnis.
• Der Fallschirm erhöht Komplexität des Flugkörpers und damit dessen Ausfallquote, sowie die Herstellungskosten.
• Ohne eine zusätzliche Vorrichtung zur elektronischen oder mechanischen Bildstabilisierung im Suchkopf können die Pendelbewegungen am Fallschirm während der Suchphase nicht ausgeglichen werden, so daß die Frequenz der Hubschrauberstrahlung in der Realität - so wie in DE 37 33 681 C1 angegeben - gar nicht erkannt werden kann.

The disadvantages of the known device with regard to the effectiveness of a weapon system are obvious:

• Incorrect range estimation leads to miss, which could only be avoided by using an additional laser range finder.
• The search phase takes place at low missile speeds. In the resulting time, the target can travel an additional distance, the overcoming of which places increased demands on the target tracking speed of the missile.
• Due to the unfavorable energy balance due to additional braking and acceleration maneuvers, increased fuel consumption and the resulting weight gain, unfavorable cost-benefit ratio.
• The parachute increases the complexity of the missile and thus its failure rate, as well as the manufacturing costs.
• Without an additional device for electronic or mechanical image stabilization in the seeker head, the pendulum movements on the parachute cannot be compensated for during the search phase, so that the frequency of the helicopter radiation cannot be recognized in reality - as stated in DE 37 33 681 C1.

The invention has for its object a user-friendly, effective Show method and a device for realizing the same with the reliable detection and control, especially of covertly operating Helicopters, d. H. without line of sight of the shooter to the target, without distance measurement, is guaranteed at low missile weight, being essential is that the search for a destination is parallel or even in the case of a flight profile in one plane can be done at a slight angle to the terrain.

This object is achieved by the measures indicated in claim 1. In Refinements and developments are specified in the subclaims and in The description below is based on a control scenario Embodiment explained and in the figures of the drawing, which is also a supplement the description are outlined.

Fig. 1

in schematischer Darstellung die operationelle Aufgabe gemäß der Erfindung,

Fig. 2

in schematischer Darstellung die Suchphase gemäß der Erfindung, und

Fig. 3

in schematischer Darstellung die Zielverfolgungsphase gemäß der Erfindung.

The invention is explained below with reference to FIGS. 1 to 3. Show it

Fig. 1

a schematic representation of the operational task according to the invention,

Fig. 2

in a schematic representation the search phase according to the invention, and

Fig. 3

the target tracking phase according to the invention in a schematic representation.

The operational task is shown schematically in FIG. One at the starting point Based on previous observations, the positioned shooter assumes that an enemy target is under cover behind a tree. In order to there is no direct line of sight between him and the target. Not here shoulder starting device shown in more detail is aligned approximately to the target, the missile launches at an elevation angle of typically 70 °. On at a height of typically 800m, the missile swings into a trajectory, which runs approximately parallel to the site.

The search phase now begins, the details of which can be seen in FIG. 2. Due to the angular position of the stationary wedge K and the rotary wedge DK, the image field axis is aligned at an angle of typically 45 ° downwards. By choosing the detector matrix DM (e.g. InSb detector matrix with 256 ^* 256 individual detectors) and the design of the lens system LS, at a flight altitude of 800 m on the surface of the earth, a search strip with a width (perpendicular to the direction of flight) of up to 1200 is typically found m trained.

Becomes a target because of it through the Rortor leaf movements in a unique way discovered modulated infrared radiation, so the missile approaches how indicated in Fig. 3, the goal according to the steering law of proportional navigation. At the same time, the rotary wedge rotates 180 ° around the longitudinal axis of the missile, so that the image field axis is now collinearly oriented to the missile axis. That starts the pursuit phase.

In addition to the target search and clear target recognition, the signal evaluation also serves SAW of lane formation. This improves the prediction of the target movement and hit accuracy. Furthermore, the measured values are one Position sensors (roll, pitch and yaw movements) in the signal evaluation used for image stabilization. The rotational and longitudinal movements of the missile can be detected quantitatively by sensors and by means of suitable Algorithms electronically stabilize the field of view on the ground, that the frequency detection of the helicopter within grid elements a laser coordinate system resting on the ground.

Claims (4)

1. A method of continuously detecting, identifying and reliably combatting helicopters operating under cover by means of a missile with an integral homing head, wherein the characteristic radiation of the helicopter, modulated by the movement of the rotor blades, is used for target recognition,
   characterised in that

   the missile comprising the homing head moves along a trajectory substantially parallel to the earth's surface during the search phase,

   in that the image-field axis extends obliquely downwards at a suitable angle during the search phase, and is collinear with the missile axis during target tracking,

   in that the search is typically carried out in a band up to 1200 m in width,

   in that the rotational and longitudinal movements of the missile are quantitatively determined by sensors, and

   in that, after signal evaluation (SE), the data from the sensors is used for electronic image stabilisation of the visual field on the ground so that, by means of the rotor-blade frequency picked up, a helicopter is identified from the image stabilised for a minimum period.
2. A method according to claim 1, characterised in that, after target recognition has taken place, the image field of the homing head is adapted to the target by the collinear alignment of the image-field axis and the missile axis.
3. A method according to claim 2, characterised in that the image field of the infrared homing head is adapted by an optically active rotating wedge (RW) during the transition from the search phase to the target tracking phase.
4. A method according to claim 1, characterised in that the optimum impact range of the missile in the target is calculated from the temporal progress of the target movement (tracing) in the final phase of target tracking.

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