GB2125151A

GB2125151A - Sighting for indirect firing

Info

Publication number: GB2125151A
Application number: GB08318369A
Authority: GB
Inventors: Herbert Becker
Original assignee: Salgad
Current assignee: Salgad
Priority date: 1982-08-10
Filing date: 1983-07-07
Publication date: 1984-02-29
Also published as: FI832804A0; DE3229775A1; GB2125151B; DE3229775C2; FI832804A; GB8318369D0

Abstract

In a method of sighting for indirect firing, at a sighting position from which can be seen directly a target which is not visible from a firing position e.g. a gun site, the distances to the target and the firing position and the angles of the sighting position to the target and the firing position are determined and transmitted to the firing position for computation with the help of a range table or the like taking into consideration other variable factors. Use is made at the sighting position, or at or near the firing position when with a gun battery, of a mini-processor into which are inserted the values of the data pertaining to ballistic factors, such as blast pressure, temperature and wind components, the values for the elevation of the gun barrel as a function of the distance from the firing position to the target, and the other established values with reference to distance and angularity. The processor computes the geometrical data for the firing position and the necessary corrections and supplies the effective data for the bearing for aiming at the target and the angle of elevation.

Description

SPECIFICATION Method of sighting for indirect firing The invention relates to a method of sighting for indirect firing, with the help of a sighting position (that of an observer and the like) from which the target can be seen directly, in the case of a target which cannot be seen from a firing position, for example that of a gun or the like.

In the case of firing over land by means of artillery when the target can not be observed from the firing position, it is usual to provide for a sighting position from which the desired target and the impacts of the shells can be observed visually to best advantage. The sighting position should as best possible be in line of sight to the target, while the firing position is in a concealed position which, however, is observable from the sighting position. Moreover, the distance to the target and to the firing position to the target and to the firing position must be determined from the sighting position and transmitted to the firing position by radio or line. The angularities are usually read off by means of an aiming circle or theodolite.For determining the distances use is made of the so-called stereoscopic range finder or, as far as the distance from the sighting position to the fitting position and to the target is concerned, of topographic maps, as these two points and the distances thereof can be ascertained from the map in favourable circumstances and with satisfactory map data. On map firing it is possible to determine the angularities between the sighting position and both the target and the firing position as a function of the map north direction. The laying angle of the gun barrel to the target is in turn determined at the firing position, which receives the respective data from the sighting position.

Regard is then had for the usual corrections as a function of the terrain and weather conditions prevailing at any given time. These corrections pertain to the data of the interior and exterior ballistic factors, hereinafter referred to as 1 EB, for example blast pressure, temperature, wind components and the like. Moreover, the differences in altitude between firing position and target, which can be determined from the map, have also to be taken into consideration. The usual range-table then offers a valuable auxiliary for the calculation of the corrective data.

With this procedure the separate data are determined or calculated partly at the sighting position and partly at the firing position, whereupon the corrective data is read off from the range-table and, if necessary, are taken into consideration by computation. After the first shot or the shots which, from experience, deviate more or less from the target, the described procedure is repeated in all particulars, until the shot hits the target. The deviations may also be brought about by map inaccuracies or incorrect position transmissions of the observer at the sighting position. The plotting of the new data after each correction involves a considerable loss of time.

Moreover, well-trained and also intelligent personnel are required. It is known from experience that the described procedure involves a high error quotient. The new firing instructions may be available only after several minutes, generally at the earliest after 10 to 1 5 minutes.

It is known on the other hand, for example with naval guns, with tank guns, and with anti-aircraft guns, in the case of which direct firing is possible and the sighting position, i.e. the observation, and the gun are close to one another, to employ electronic calculators which take into consideration the appropriate corrections for the changes in movement of one's own or the hostile object. With indirect firing, in the case of which the sighting position, i.e. the observer, is situated remote from the firing position, the computing activities are carried out at two different positions each of which is dependent upon the other for important data. This not only requires time but also incorporates sources of error.

The object of the invention is to facilitate substantially and to speed up the establishment of the firing data even in the case of the method of sighting and indirect firing of the kind mentioned and explained in the beginning. The method of sighting in accordance with the invention for indirect firing is distinguished by the use at the sighting position, i.e. at the observation point remote from the firing position, of a miniprocessor into which the values of the 1 EB data, the geometrical values from the sighting position to the target and to the firing position with reference to distance and angularity, and the values for the elevation of the gun barrel as a function of the distance from the firing position to the target taking into consideration contingent differences in altitude of terrain, are inserted in advance in tabulated form.

The mini-computer automatically calculates first of all the geometrical values for the firing position to target distance and the angle at which the gun barrel is set in the horizontal plane.

Thereafter automatically follow the corrections according to the 1 EB data, whereupon the elevation of the gun barrel and, if necessary, also the instruction concerning the charge to be used are determined by the computer. Through the mini-processor placed in position at the observation position situated remote from the firing position are given the conclusive values for the bearing angle for aiming at the target and the angle of elevation. These values are passed on to the firing position by radio and can there in fact be converted immediately to specify the target number and the charge to be used. As a result, there is a short gun-laying time bound up with an exact automatic computation. This leads to substantial gains in time and economically, particularly to the possibility of a rapid engagement of the target and the attainment of good hitting shots or direct hits.The danger of a target shift is substantially less than with the methods hitherto existing. Savings are made in time and expenses for expensive adjustment fire.

In the procedure according to the invention shot data may be possible in a few minutes. Moreover the training of the personnel is substantially Jsimplified.

In accordance with a further feature of the invention, the mini-processor may also be equipped with an electronic range finder.

Moreover, the mini-processor may at the same time also be coupled functionally with a theodolite or an aiming circle. The automatically determined values are in that case processed directly in the computer without the observation position having to be involved in transmission services.

The mini-processor may be coupled with a monitor at which the observation and the automatically-determined values can be read off and, if necessary, checked.

The mini-processor is equipped with suitable chips and cassette tapes or discs; in conformity with the characteristics of the weapon (cannon, howitzer, rocket launcher, mortar, and the respective calibers). The routine data for the 1 EB--correction values are inserted into the computer before beginning the activities at the observation position, just as are the range-table values co-ordinated with the gun.

The respective geometrical angular relationship to the target and to the firing position of the site of the sighting position, which is situated remote from the firing position, may be oriented by means of the triangle at the intersections of which are the firing position, the sighting position and the target. The orientation may be provided with dependence on a map grid the gun with its aiming circle and also the aiming circle of the observer being co-ordinated with north of the map. Thereafter the tabular values to be inserted into the mini-processor are prepared.

One possible siting of the three interdependent positions is shown in the accompanying drawing.

The firing position, i.e. the gun position, is shown at A, the sighting position, i.e. the observation position, at B, and the desired target at C. The measures for the target and also, if necessary, the firing position can be taken from the aiming position by means of a theodolite or director, whereby the angle (x is determined. At the same time the distances of sighting position to target and of sighting position to firing position can also be measured. If the firing position A is not visually accessible from the sighting position B, there can be set up a second sighting position which is operatively analogous to the first.

The angle (x can be determined by measurement and deduction from the map. The target C is not directly visible from the firing position A. The lengths of the sides b and c and the angle a formed by these sides are consequently known from the triangle A, B, C.

Accordingly, the third side can be calculated trigonometrically with reference to distance from firing position to target and the angle B between the side a and the side c, which the miniprocessor accomplishes, specifically according to the equation a2=b2+c2-2bc.cos x aMa2 The theoretical bearing for aiming at the target and the angle of elevation of the gun barrel are consequently known. The corrections allowing for the 1 EB routine data and the range-table data preset for the weapon then result automatically through the mini-processor.

Through the use of a map with a map grid the respective angles can be determined in tabulated form with a regard to the north direction on the map, the mini-processor automatically establishing and making known the data required at the gun.

The calculation of the data after the manner of the described trigonometry can probably be carried out more accurately and quickly.

It is, moreover, intended that the miniprocessor used is functionally connected with a specific communication apparatus which is not adapted for speaking but serves only for transmitting wholly specific data or concise information, namely a) target number, b) bearing, c) angle of elevation, d) charge, e) fire command.

The data is, of course, transmitted through a previously inserted coding and using varying frequencies, in order that the transmission is safeguarded against interception.

In many cases it is recommendable that the mini-processor, that is the mini-computer, is not at the sighting position but is at or near the firing position A. This is especially the case when firing is effected at the firing position by a battery, i.e.

by a number of guns, it then being necessary to make use from time to time of different rangetable data, e.g. concerning elevation, wind direction and the like, for the individual guns situated at a considerable spacing apart from one another. In doing so, that different data of the respective sites of the individual guns of the battery must be presented in advance to the minicomputer, so that the appropriate data for each gun of the battery is instantly available.

Claims

1. A method of sighting for indirect firing with the help of a sighting or observation position from which can be seen directly a target which is not visible from a firing position such as a gun site, in which the distance to the target and to the firing position and the angle of the sighting position to the target and to the firing position are determined at the sighting position and transmitted to the firing position, and at the firing position the laying angle of the gun barrel to the target is ascertained and through a range-table or the like the data for the elevation of the gun barrel and the interior and exterior ballistic factors (1 EB) for example blast pressure; temperature, wind components and the like, are taken into consideration, use being made at the sighting position, i.e. at the observation point remote from the firing position, of a mini-processor into which the values of the 1 EB data, the values for the elevation of the gun barrel as a function of the distance from the firing position to the target, and the geometrical values from the sighting position to the target and to the firing position with reference to distance and angularity, are inserted in advance in tabulated form, whereupon the computer calculates and determines the geometrical values for the firing position and thereafter allows for the corrections with the aid of the inserted 1 EB routine data and the rangetable values, and communicates the actual data for the bearing angle for aiming at the target and the angle of elevation, e.g. through a monitor or the like.

2. A method according to claim 1, in which the mini-processor is functionally coupled with an electronic range finder and/or a theodolite (director).

3. A method according to claim 1 or 2, in which the mini-processor is coupled with a communication apparatus which is not adapted for speaking and is equipped for transmitting only the data of target number, bearing, angle of elevation, charge, and fire command.

4. A modification of the sighting method according to any one of claims 1 to 3, in which the micro-processor is used'at or near the firing position with several guns, the predeterminable data of each individual gun of a battery or the like being inserted in advance into the mini-computer.