1 Title of the invention

Harmonization of Weapon Systems Without Jacking Up the Helicopter

2 Field of invention

The present invention relates to improved harmonizing systems and methods for helicopter weapons and other suitable systems without jacking up and leveling the helicopter.

3 Background of Invention

Helicopter/Aircrafts and onboard weapon systems need to be harmonized to designed reference points to provide highest degree of weapon system (Rockets and missiles) accuracy during operation. Presently this involves jacking up, leveling and aligning the helicopter and all the onboard system references to a harmonization board on which design reference points are marked. This method involves significant time and man power efforts for jacking up and leveling of helicopter and the harmonization board used is bulky in size as weapons references are to be projected perpendicular to the harmonization board in parallel manner.

The primary objective of the invention is to harmonize the helicopter and weapon stations to design reference points using a line laser unit, a compact harmonization board to avoid the need for jacking up and levelling the helicopter which reduces time, effort and board size significantly.

3.1 Prior Art

Previously, the harmonization of helicopter was carried out by placing harmonization board at specified distance from onboard helicopter reference. The helicopter is jacked up, levelled and helicopter references are transferred to corresponding design coordinates on harmonization board using water level method and thread (for levelling and centre line marking), the parallel weapon stations are harmonised to corresponding station parallel reference coordinates on harmonization board using a bore sighting device.
The following drawbacks of the existing method were observed:

• Jacking up and levelling of helicopter requires more effort and time

• Transferring helicopter references to harmonization board by using water level method and marking through thread is a cumbersome process

• Due to projection of weapon station references parallel to helicopter references, board is bulky in size and is difficult for handling, storage and transportation,

US006040854A publication dated 21/03/2000 discloses the claims for usage of an electro-optical process and apparatus for the Static harmonization or calibration of weapon systems and aircraft having onboard systems which are to be measured with respect to one another and on the fuselage axis.

WO 2012/177449 A1 publication dated 27/12/2012 claims for usage of a portable near infrared emitted lighting diode source and photogrammetry technique for boresight harmonisation of aircraft.

Present invention discloses a concept for harmonising the helicopter and weapon stations using a line laser unit and a harmonization board which is distinguishably different from the arts disclosed in US006040854A and WO 2012/177449 A1. The art disclosed herein this article is compact and offers quick change over time with less efforts.

4 Summary of the present invention

Th? prime objective js to avoid jacking up and levelling the helicopter and t_o optimize harmonization board size thereby saving time and effort. The present invention deals with harmonizing helicopter and weapon systems using a line laser unit without jacking up and leveling the helicopter.
5 Brief description of drawings

Figure-1: shows assembled view of line laser unit assembly (600) with line laser unit (601) fixed to adapter plate (602). Line laser unit consists of three pendulums which generates three mutually perpendicular laser planes i.e , vertical laser plane (601a), horizontal laser plane (601b) and lateral laser plane (601c). Line laser unit (601) automatically levels to neutral position when placed on inclined surfaces. Automatic/self-leveling facility is disabled by arresting pendulum movement to carryout harmonization without jack up. Entire assembly is mounted on a mounting plate (603).

Figure-2: shows the close view of line laser mounting bracket assembly (500) with line laser unit mounting plate (501), pitch & roll adjustment fasteners (502), support bracket (503). Entire assembly is installed on helicopter interface bracket (504).

Figure-3: shows the assembled view of weapon harmonization tool (400) which consist of harmonization bracket (401), clamping bracket (402), sleeve (403) and weapon station interface bracket (404). Harmonization bracket (401), clamping bracket (402) and sleeve (403) are assembled using fasteners. Harmonization bracket (401) contains holes (401a) for each weapon station (Hole position is arrived based on theoretical shift of weapon station reference (center line) to centerline of helicopter at a specified distance about a pivot point in converging manner) and a pivot point (401b).

Figure-4: shows the assembled view of harmonization board (300) with support structure (301), harmonization panel (3Q2), lateral movement mechanism (303), vertical movement mechanism (304) and roll angle adjustment mechanism (a pivot point (305a) and slotted holes (305b)) (305). Theoretical design references are marked on harmonization panel (302) i.e., helicopter center line reference (302a), horizontal line reference (302b).

Figure-5: Schematic view of helicopter (100) positioned on flat & cleaned surface (50) with weapon releasing unit (201) installed at weapon station
(200), line laser unit mounting bracket assembly (500), harmonization board (300) and weapon harmonization tool (400) in a harmonization environment.

Figure-6: Schematic view of helicopter (100) installed with line laser unit mounting bracket assembly (500) and aligning helicopter (100) references to harmonization board (300) using line laser unit assembly (600) in a

harmonization environment.,

Figure-7: Schematic view of weapon station (200) installed with weapon harmonization tool a (400) and aligning weapon station (200) references to harmonization board (300) using line laser unit assembly (600) in a harmonization environment.

6 Detailed description of invention

The proposed invention is a method of weapon station harmonization in converging manner which eliminates the need of bulky boards thus enables to make boards modular in construction in less weight and compact size so that it can be transported in the aircraft/helicopter at ease. This section discloses the harmonizing devices and the process for a helicopter (100) and its weapon station (200) without jacking up for leveling the helicopter.

As shown in Figure-6, the helicopter (100) with weapon stations (200) is positioned on a flat and cleaned surface (50). Line laser unit mounting bracket assembly (500) is installed on helicopter (100) at pre-determined location (101) as shown in Figure-6. Harmonization board (300) is placed in front of helicopter (100) at a specified distance (102) of Figure-5. Weapon harmonization tool (400) is installed on weapon station (200) intended for harmonization;

Helicopter (100) harmonization: Pitch & roll angles of helicopter (100) are measured at specified location (103) of Figure-5 using clinometer and recorded. Line laser unit mounting plate (501) of Figure-2 is adjusted to match with helicopter (100) pitch & roll by means of adjusting the lengths of the fasteners (502) provided on support bracket (503). Line Laser unit assembly (600) shown in Figure-1 is placed on line laser mounting plate (501) at specified location (501a) of Figure-2.

Line laser unit (601) shown in Figure-1 is switched on and it’s both horizontal and vertical laser planes are projected. The Line laser unit assembly (600) is adjusted in such a way that the vertical laser plane (601a) is aligned with center plane (100a) that is passing through symmetrical plane of helicopter (100). Harmonization panel (302) shown in Figure-4 is moved laterally (306) to bring the pivot point (302c) of center line (302a) close to vertical laser plane (601a) as shown in Figure-6 using lateral movement mechanism (303). Harmonization board panel (302) shown in Figure-4 is moved vertically up/down (307) to match with horizontal line (302b) with the horizontal laser plane (601b) which represent horizontal reference of the helicopter (100) as shown in Figure-6 using vertical movement mechanism (304).

Finally, as shown in Figure-6 harmonization board panel (302) is rotated (308) about pivot point (305a) through roll angle adjustment slots (305b) such that the center line (302a) and horizontal line (302b) of harmonization panel (302) is aligned with vertical laser plane (601a) and horizontal laser plane (601b) of line laser unit assembly (600).

The proposed invention method using a line laser unit (601) mounted on laser unit mounting assembly (500), a harmonization board (300) and weapon harmonization tool (400) avoids the necessity for jacking up and levelling the helicopter (100) by following the process explained above. Methodical usage of aforementioned devices and the process saves the time and effort without compromising any aspect of harmonization since there is no jacking up and levelling of the helicopter (100). Once the helicopter (100) is harmonized, onboard weapon systems can be harmonized as per respective procedures described hereunder.

Weapon Station (200) Harmonization: Weapon harmonization tool (400) shown in Figure-3 is installed on weapon station (200) intended for
harmonization as shown in Figure-5. The line laser unit assembly (600) is installed on a harmonization bracket (401) of weapon harmonization tool

(400) .

The harmonization bracket (401) along with line laser unit assembly (600) is rotated through sleeve (403) such that roll angle of harmonization bracket

(401) is matched with roll angle of helicopter (100).

Line laser unit is switched on and vertical laser plane (601a) is projected on to harmonization board (300). The line laser unit assembly (600) is rotated about vertical axis at pivot point (401b) to match with hole (401a) of respective weapon station (200) reference which are marked on harmonization bracket (401) and locked using a fastener.

Ideally, the vertical laser plane (601a) aligns to center line (302a) of harmonization panel (302) as shown in Figure-7. The difference may exist between the center line (302a) and vertical laser plane (601a) depends up on weapon release unit (201) installation. The difference between center line (302a) and vertical laser plane (601a) is the deviation with respect to center reference line of weapon station (200).

The harmonization process consists of either adjustment of the stations to align with center line of the board or incorporating (or by feeding) the same difference in to the weapon system software as correction depending upon design of weapon system in order to achieve the better operational accuracy.

Proposed invention is not limited to one weapon station (200) but can be extended to plurality of stations as well as the plurality of the weapons (Rockets and Missiles) within the scope of the invention disclosed in this article. Wherein the plurality of stations means namely inboard station or outboard station on both port and starboard sides of the helicopter (100) also considered within the scope the invention disclosed in this article. This is by means of provision of plurality of holes (401a) accordingly on
harmonization bracket (401) and adapting the proposed procedure for the harmonization respective weapon station (200).

The particulars disclosed in this article are exemplary representations of the invention, it is also possible that the invention may be modified and practiced in equivalent but different ways or arrangements by one who is skilled in the art with the hejp of the details described in this manuscript. Therefore, all such variations are to be considered within the scope and spirit of the invention disclosed in this article. Accordingly, the protection is sought.