Patent Application
20090188384
The present invention relates to apparatus, a kit and a method for aligning a weapon system with a vehicle to which the weapon system is mounted. The present invention relates more specifically to apparatus, a kit and a method for aligning a rocket launcher with an aircraft, e.g. an AH-64 Apache helicopter.
The AH-64 Apache helicopter was first used in combat during the 1989 invasion of Panama, Operation Just Cause. The AH-64A Apache and the AH-64D Apache Longbow have played important roles in several Middle Eastern wars, including the Gulf War, Operation Enduring Freedom in Afghanistan, and Operation Iraqi Freedom in Iraq. These aircraft were proven to be excellent tank hunters and also destroyed hundreds of armoured vehicles.
However, recent reports indicate that the Apache is vulnerable to ground forces in certain environments, such as when operating in urban terrain. Since 2003, Iraqi ground troops and insurgents were able to damage propulsion and flight control systems with ground fire, sometimes forcing the helicopters to make immediate emergency landings or shooting them down. During Operation Iraqi Freedom, some Apaches were damaged in combat, including one captured by Iraqi troops near Karbala on 24 Mar. 2003, shown on Iraqi television. The captured helicopter was destroyed via air strike the day after it was captured. More recently, in January and February 2007, two Apaches were lost, along with their crews, to Iraqi insurgent ground fire.
There are various factors that contribute to this vulnerability. Apaches were designed to engage and destroy armour at safe ranges, where they could not be fired upon. However, in Iraq, for example, the close quarters and ample cover afforded by the urban environment, make it easy for ground forces to attack at close ranges (50-850 m). This environment brought out the Apache's vulnerability to close range attacks from heavy caliber machine guns (0.5 inch). Also, since the Apache is only capable of firing at a single target at a time, it is vulnerable when attacked from several dispersed positions.
In addition, the rocket system on these helicopters was designed as an area weapon system and not a point weapon system. A point weapon system provides high accuracy to a target and requires a relatively small amount of ammunition. On the other hand, an area weapon system is typically used to fire in rapid succession and spread a large amount of ammunition over a large area. However, area weapon systems are known to suffer from a lack of accuracy which can be detrimental to the safety of the aircraft and crew, particularly in situations as described above.
As a result of these inaccuracies and the associated risks, e.g. firing in the direction of ‘friendly forces’ or civilians located in the target area, it is known for qualified Apache pilots to deploy a rocket when the aircraft is within 1500 m of the target. US and Dutch pilots tend to deploy rockets when within 1000 m of the chosen target. However, this also means the target is close to the aircraft and hence the vulnerability of the aircraft is increased and the safety of the crew is put at risk.
A cause of these inaccuracies is associated with the mounting arrangement currently used to mount the rocket launchers to the Apache wing-stubs. Rocket launchers are mounted to each wing-stub via sway braces from which the rocket launcher hangs. A number of bolts attach the rocket launcher to the sway brace. A known problem is that of accurately aligning the rocket launcher with a datum on the aircraft before the bolts are tightened. Although the rocket launcher is positioned accurately and pointing in a correct direction, it is not aligned correctly with the aircraft datum. Hence, the true direction in which the rocket launcher is pointing is unknown. A result of this is an unknown Desired Mean Point of Impact (DMPI) for the rockets deployed from the rocket launcher. This problem of alignment can be made worse when the aircraft is standing at an angle, e.g. when at rest on uneven ground.
Advances in technology, particularly on the battlefield, have resulted in the requirements of today's warfare being very different to that of yesteryear. Known attempts to increase the accuracy of area weapon systems include a procedure used by the US Army. The procedure is not an alignment procedure but is an additional procedure when mounting the rocket launchers to the Apache helicopter. The procedure describes how to correctly attach the rocket launchers to sway braces mounted on the aircraft. The procedure was published in 1992 and is titled ‘Procedure for Sway Brace Bolt Adjustment following Missile/Rocket Launcher Installation’. Despite following the above procedure, the accuracy in alignment of the rocket launcher with the aircraft datum remains inadequate.
Means to accurately align a weapon system, e.g. rocket launcher, with a vehicle, e.g. an aircraft, are required. Such means may be used during installation of the weapon system to the vehicle and to ensure the weapon system remains aligned during service. Such means may comprise apparatus having any one or more of the following features:
According to a first aspect of the present invention, apparatus for aligning a weapon system mounted on a vehicle is provided, the apparatus comprising:
It will be understood that the term ‘vehicle’ may include any structure to which a weapon system is mounted and, particularly, mobile structures including ground, sea and air vehicles, e.g. a helicopter.
It will also be understood that the term ‘weapon system’ includes all weapon systems which require accurate alignment with a vehicle, on which they are mounted, to achieve required target accuracy. The term particularly includes weapon systems which deploy a shell, e.g. a rocket, from a single chamber or launch pod comprising a plurality of chambers, e.g. a rocket launcher.
Suitably, the reference means may allow alignment of the apparatus with the reference datum on the vehicle in one or more of roll, pitch and yaw orientations. This allows the weapon system, with which the apparatus is mounted, to be accurately aligned with a reference datum on the vehicle in one or more of these orientations. Accurately aligning the weapon system with a known reference datum on the vehicle in one or more of these orientations advantageously ensures weapon system-to-target accuracy and, as a result, pilot confidence is high. To achieve the desired accuracy, it has been found that the rocket launcher must be sufficiently aligned with a reference datum, preferably on the aircraft, to within 0.1 degree in one or more of pitch, yaw and roll orientations.
Where alignment is required in pitch and yaw orientations, only a single reference datum may be required. For alignment in roll orientations, more than one reference datum on the vehicle may be required. However, it will be understood that alignment of the weapon system in one or both of pitch and yaw orientations is essential for achieving high target accuracy and alignment in roll orientation is less important. The reason for this is that pitch and yaw orientations have a direct effect on the direction in which the weapon is facing before deployment from the weapon system, whereas roll, about a weapon axis, does not.
Preferably, the apparatus will provide accuracy in alignment with the reference datum of from −0.5 to +0.5 degrees. Further preferably, the apparatus will provide accuracy in alignment with the reference datum of from −0.1 to +0.1 degrees.
A suitable reference datum may include a reference plane or point, e.g. the nose of a helicopter, a rivet or a visible spot adhered or painted on the vehicle body. A suitable reference datum may also include a reference line, e.g. a joining line where two or more body panels meet or a visible line adhered or painted on the vehicle body.
Preferably, the reference means comprises a suitable reference on the apparatus with which the reference datum on the vehicle may be aligned by suitable aligning means. A suitable reference on the apparatus may include, for example, a reference plane, point, mark, line, notch or sticker. Preferably, the reference on the apparatus is a reference plane. Suitably, the reference plane may be a horizontal plane.
Suitably, the reference means may be aligned with the reference datum on the vehicle by using suitable aligning means and the reference means may be adapted to support the aligning means. Suitable aligning means may comprise a clinometer, e.g. an inclinometer, but may comprise any suitable aligning means including electrical, optical and mechanical means, such as, for example, a mechanical sight used to take a transit bearing with the reference datum on the vehicle.
The reference means may suitably be adapted to support the aligning means and may be adapted to ensure its position is fixed relative to the reference means during use. For example, the securing means may comprise mechanical means, adhesive or a magnet. This may be particularly important when it is necessary to use the apparatus in adverse weather conditions, e.g. strong winds.
Preferably, the reference means comprises a platform.
Suitably, the mounting means may mount on, in or around a portion of the weapon system. The weapon system may comprise one or more weapon chambers from which a weapon is deployed, e.g. a rocket, and the mounting means may suitably mount the apparatus using one or more of the weapon chambers.
The one or more weapon chambers may be a substantially tubular weapon chamber. The mounting means may comprise at least one elongate portion adapted to be received by at least one of the weapon chambers. Alternatively, the mounting means may comprise other suitable means to mount the apparatus in alignment with the weapon system, e.g. screws, clamps or adhesive.
Preferably, the at least one elongate portion is slidably received by the at least one weapon chamber. This provides a quick and simple means of mounting and removing the apparatus on, and from, the weapon system.
Preferably, the mounting means comprises first and second elongate members.
Preferably, the first and second elongate members are suitably spaced to provide the apparatus with adequate balance and rigidity when mounted in alignment with the weapon system.
Suitably, the first and second elongate members are received by two corresponding weapon chambers of the weapon system. Preferably, the two corresponding weapon chambers are outer weapon chambers of a launch pod comprising a plurality of weapon chambers. Preferably, the corresponding weapon chambers are substantially spaced on a horizontal plane.
Suitably, the first and second elongate members are circular in cross section and have a diameter substantially similar to the diameter of the corresponding weapon chambers in which they are received. This ensures a ‘snug’ fit is achieved with the weapon chambers and any play between the elongate members and weapon chamber walls is kept to a minimum.
Preferably, the first and second elongate members are hollow and tubular. This advantageously ensures the weight of the apparatus is kept to a minimum.
Suitably, the first and second elongate members have a closed end. Preferably, both ends of each elongate member are closed. This advantageously prevents debris, or similar, from entering and becoming lodged inside each member which may result in corrosion.
Suitably, the apparatus comprises attachment means to attach the reference means to the mounting means. The platform may be attached to the elongate members via suitable joining techniques known in the art. Such techniques may, for example, include welding.
Alternatively, the attachment means may be substantially mechanical to advantageously provide ease of assembly and allow the apparatus to be disassembled for transit or storage purposes. The attachment means may comprise a nut and bolt arrangement to clamp the platform and elongate members together.
Alternatively, at least one threaded hole may be provided in each elongate member and corresponding bolts may clamp the platform and elongate members together. The threaded holes may be in an upper or lower side of the elongate members or in a closed end of each elongate member to allow the platform to butt up against the closed ends.
Alternatively, the platform may be disposed within longitudinal side slots in an inner side of each elongate member. Suitably, the at least one threaded hole may be disposed near opposite sides of the platform and corresponding bolts may clamp the platform, within the longitudinal side slots, to the elongate members.
Conveniently, the bolts may comprise a handle or lever to provide a mechanical advantage to the user when tightening or loosening the bolts. The handle or lever may conveniently be provided on the head of each bolt. Alternatively, the bolt heads may be knurled.
Alternatively, the attachment means may comprise a toggle arrangement suitably adapted to clamp the platform and elongate members together. Conveniently, the toggle arrangement may comprise a lever and a bolt, the arrangement being adapted to apply a tension in the bolt when the lever is actuated to clamp the arrangement together, e.g. using an offset cam arrangement. The lever may be released to unclamp the arrangement when required.
Preferably, the attachment means further comprises adjusting means to allow one of the first and second elongate members to be adjustable relative to the other. Suitably, one of the first and second elongate members is fixed relative to the platform and the other is adjustable. This advantageously allows the apparatus to mount in alignment with weapon systems, e.g. rocket launchers, having differently spaced outer weapon chambers which receive the first and second elongate members. A degree of adjustment of one elongate member relative to the other also provides means to compensate for possible effects of material expansion and contraction when the apparatus is subjected to extreme temperatures.
Preferably, this adjustment is in a horizontal plane.
Suitably, a first slot may be provided and adapted to provide lateral adjustment of one elongate member relative to the other elongate member. Preferably, the first slot is disposed near a side of the platform and the attachment means engages with the first slot.
Additionally, a second slot may be provided and adapted to provide longitudinal adjustment of the platform relative to one of the first and second elongate members. Suitably, the second slot may be disposed near a side of the platform and the attachment means may engage with the second slot. Suitably, the second slot may be disposed perpendicularly to the first slot.
Alternatively, one or both of the first and second slots may be provided in one of the first and second elongate members.
Preferably, the platform is adjustable relative to the first and second elongate members. Suitably, longitudinal side slots may be provided in each elongate member being horizontally aligned and adapted to allow forward, aft and lateral adjustment of the platform, relative to the elongate members.
Preferably, the platform is substantially sheet-like having a thickness offering adequate stiffness to withstand a harsh environment, such as those typically experienced by the military. In other words, the platform must be adequately stiff without being unnecessarily heavy.
Preferably, the platform is rectangular in shape. However, the platform may be any suitable shape. For example, the platform may be substantially triangular, the apex of which points away from the weapon system when mounted in alignment with the apparatus.
Suitably, the apparatus is manufactured from lightweight, high strength alloy material. However, the apparatus may be a plastics material.
According to a further aspect of the present invention, a kit of parts for aligning a weapon system mounted on a vehicle is also provided, the kit comprising:
As described herein, suitable aligning means may comprise a clinometer or any suitable electrical, optical or mechanical aligning means, e.g. a mechanical sight used to take a transit bearing with a datum on the carrier.
The kit may further comprise any one or more of:
According to a further aspect of the present invention, a method of aligning a weapon system with a vehicle on which it is mounted is also provided, the method comprising:
The method may further comprise one or more of the following steps:
The present invention will now be described by way of example only, with reference to the accompanying drawings, in which:
As shown in
The platform (12) is attached to each of the first and second elongate members (14,16) via a bolt (20) which threads into a corresponding threaded hole (21) disposed at an end of each elongate member (14, 16). Other suitable attachment means may be used including welding or a simple nut and bolt arrangement.
Once the apparatus (10) is securely mounted in alignment with the weapon system (55), suitable aligning means may be used to align the platform (12) with a reference datum on the vehicle. A suitable reference datum may include a datum point or line painted or adhered on the vehicle or could be a feature of the vehicle, e.g. a rivet or join line where two or more body panels meet. Suitable aligning means may include an inclinometer which is placed on the platform (12) and used to align the platform (12) with the reference datum on the vehicle. However, other suitable aligning means, including electronic, mechanical and optical, may be used.
Alternatively, the platform (12) may be attached above, below or between the first and second elongate members (14, 16).
The adjustable second elongate member (16) is adjustably attached to, or near, an opposite side of the platform, relative to the fixed first elongate member (14). A nut and bolt arrangement (34, 36) clamps the platform (12) and adjustable second elongate member (16) together. A handle or lever (26) is conveniently provided on the bolt head (34) to aid tightening and loosening of the arrangement (34, 36). Alternatively, the arrangement (34, 36) may be reversed and the handle or lever (26) may be provided on the nut. Alternatively, the bolt head (34) or nut may be knurled.
The second elongate member (16) is adjustable relative to the fixed first elongate member (14) via a first slot (32) disposed in the platform (12). The first slot (32) is disposed laterally in the platform (12) and is adapted to engage with the nut and bolt arrangement (34, 36). The first slot (32) provides lateral adjustment of the second elongate member (16) relative to the first elongate member (14). Advantageously, this allows the apparatus (10) to be mounted in alignment with weapon systems having weapon chambers (52, 54) of different spacing.
Additionally, a second slot (not shown) may be provided in either the platform (12) or adjustable second elongate member (16) to allow for longitudinal adjustment of the platform (12). The second slot may be disposed longitudinally in the platform (12) or, alternatively, in the upper or lower surface of the second elongate member (16), and would correspond with the first slot (32) and nut and bolt arrangement (34, 36). The side slots (24) disposed in the first and second elongate members (14, 16) allow for this longitudinal adjustment of the platform (12). Limits to the adjustment of the second elongate member (16) and the platform (12) may be provided by the first slot (32), second slot (not shown) and side slots (24) and the limits governed by the lengths of the slots.
The adjustment of the second elongate member (16) relative to the platform (12) and first elongate member (14) also provides means to compensate for expansion and/or contraction effects of the apparatus material during extreme temperatures.
The platform (12) may be any suitable shape to provide means to mount suitable aligning means, e.g. a clinometer, with the apparatus and to provide adequate stiffness and rigidity to the apparatus. The first and second elongate members (14, 16) are preferably hollow and to ensure the apparatus is lightweight. In addition, the apparatus is preferably a material which is lightweight and which provides adequate strength, e.g. aluminium.
The apparatus may be simply disassembled for storage purposes and quickly re-assembled for use.
A kit may include the apparatus and suitable aligning means, e.g. a clinometer, for aligning a weapon system (55) with a vehicle on which the weapon system (55) is mounted. The kit may also include one or more of a reference datum to be mounted on the vehicle, an instruction sheet or manual, a tool, e.g. an Allen key, suitably adapted to assemble or disassemble the apparatus, and storage means.
To align a weapon system (55), e.g. a rocket launcher, with a vehicle, e.g. an aircraft, on which the weapon system (55) is mounted, the apparatus (10) is first assembled, if required. The apparatus (10) is mounted in alignment with the weapon system (55) by sliding the first and second elongate members (14, 16) into corresponding weapon chambers (52, 54) on the weapon system (55). If required, the spacing between the first and second elongate members (14, 16) may altered by adjusting the second elongate member (16) relative to the first elongate member (14). This advantageously allows the apparatus (10) to be mounted in alignment with weapon systems having weapon chambers (52, 54) of different spacing. This also provides adjustment of the apparatus (10) to compensate for possible material expansion and/or contraction effects in extreme temperatures.
Once the apparatus (10) is mounted in alignment with the weapon system (55), an aligning means, e.g. a clinometer, may be placed or mounted to the platform (12). The clinometer, e.g. an inclinometer, can be used to accurately align the platform (12) with a suitable reference datum on the vehicle. As described above, a suitable reference datum may include a datum point or line painted or adhered on the vehicle.
A suitable aligning means, e.g. an inclinometer, can be used to align the weapon system (55) is one or all of pitch, yaw and roll orientations. As described herein, pitch and yaw orientations are typically most important for weapon system alignment requirements. Other suitable aligning means may be used.
The weapon system (55) is adjusted in one or all of these orientations via the mounting system mounting the weapon system (55) to the vehicle, e.g. mounting brackets or bolts. Where the inclinometer indicates a misalignment between the platform (12) and the reference datum, the weapon system (55) is adjusted accordingly until alignment is achieved. Once alignment is achieved, the mounting system, e.g. mounting brackets or bolts, attaching the weapon system (55) to the vehicle is tightened to ensure the weapon system (55) is securely mounted to the vehicle. Finally, the apparatus (10) is removed from the weapon system (55) and, if required, disassembled for storage purposes.
| Number | Date | Country | Kind |
|---|---|---|---|
| 0611026.6 | May 2006 | GB | national |
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/GB07/50305 | 5/30/2007 | WO | 00 | 12/18/2008 |
