The Development of an Automatic Multi Calibre Weapon System

 

 

A. van Heerden; M. Kleingeld; E.H. Mathews; M.F. Geyser

Centre for Research Continued Engineering Development (CRCED), North West University, Pretoria, PO Box 2156, Faerie Glen 4, 0043, Pretoria, South Africa

 

 

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ABSTRACT

The competitive drive in the armaments industry resulted in the development of a superior product by the South African National Defence Force (SANDF), which provided the security forces with a world class product. Such a weapon would provide the SANDF with the capability of being deployed anywhere in the world for peacekeeping purposes, enabling the firing of foreign ammunition without intensive use of logistical support. Armament Corporation of South Africa (ARMSCOR requested Vektot^b to develop a multi calibre, rapid firing weapon. The GAMA (Gun Automatic Multiple Ammunition) a unique, multi calibre, rapid firing weapon was developed with the aid of simulation and testing. Simulation at the time did not fully support the contemporary sophisticated tool sets, and therefore a method was designed to use simulation and experimental development interactively. Simulation models were generated modularly whilst phasing it with the acquirement of experimental test data. The primary focus was to develop a weapon capable of firing a range of ammunition which would be fitted to the South African Air-Force (SAAF) new Light Utility Helicopter (LUH). The secondary purpose resided in the marketing of such a product internationally. At the same time, the processes used demonstrated that the local industry can be rated to be on the leading edge of technology.

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Nomenclature

Abbreviations

AP Armour Piercing

ARMSCOR Armament Corporation of South Africa -Procurement Division of the SANDF

CAD Computer Aided Design

CNC Central Navigation Computer

COC Certificate of Conformance

CRCED Centre for Research Continued Engineering Development

CSIR Council for Scientific and Industrial Research

DLSL Denel Land Systems Lyttelton

ESR Electro Slag Re-melting / Refining

GAMA Gun Automatic Multiple Ammunition

HP High Pressure

LUH Light Utility Helicopter

MPI Mean Point of Impact

MRI Master Record Index

HEI High Explosive Incendiary

HEIT High Explosive Incendiary with Tracer

NDT Non Destructive Testing

PMP Pretoria Metal Pressings (Ammunition Manufacturer) - A Division of Denel

Rds Rounds

SAAF South African Air-Force

SANDF South African National Defence Force

SAPHEI Semi-Armour Piercing High Explosive Incendiary

TP Target Practice

TPT Target Practice with Tracer

 

1. Introduction

1.1 Background

Traditionally, development relies on the standard systems engineering approach for the development of new products, and this by its very nature can be a time consuming process. The systems engineering processes consist of the building of hardware models before it eventually leads to the production of the final product. Laboratory and field tests are performed on the hardware and the results are used as a system design feedback. Hardware models are used for evaluation also obtaining answers to questions as the project progresses. Building these hardware models also incorporating further design changes, is a costly and a time consuming business. The embarrassment in correcting designs could be avoided by using the power of simulation. The availability of information reduces therefore risk.

The complexity in the development of a unique multi calibre weapon system, urges us to follow the route of development by means of simulation and testing. The reason is that the foreign ammunition was not available within the Republic of South Africa and development could not be stalled awaiting the arrival of the new purchased ammunition. The complexity in the development of the multi calibre weapon can best be appreciated when referring to figure 1.

 

 

This figure clearly illustrates the variance in shape and size of each round, each having its own unique performance. The life expectancy of a weapons system in general is also limited by the availability and the life expectancy of the specific ammunition it utilizes. Weapon systems designed to grow toward alternative or new types of ammunition are definitely an advantage. Adaptive procedures in ammunition handling, weapon maintenance and control procedures would be required, but the logistical support and training of personnel will only need to be limited to the amended procedures resulting from the incorporation of the new calibres¹.

The development of GAMA proved to be successful, reducing risk, thus delivering a matured product in very short time scales. Laboratory and field test results when used interactively with simulation, produced a scientifically matured system that enables Denel Land Systems Lyttelton (DLS L) to produce a prototype that satisfactorily conforms to the client's request. Simulation helped to make better decisions earlier in the development cycle of a project. Simulation therefore reduces the time line in the design cycle, and this in turn limits the production of prototypes, which results in the lowering of development costs.

1.2 Contribution of this study

This study resulted in the design, manufacturing and evaluation of a weapon system capable of being deployed anywhere in the world, utilising a wide range of ammunition².

The primary aim of the weapon is to be fitted onto a LUH, (figure 2), for self defence purposes in air to air and air to ground scenarios^{3 4 5 6}. Additionally, it is marked as a replacement for existing GA1 weapon^7,8.

 

 

The uniqueness of the development of the GAMA can be underlined by the fact that it is able to fire various types of ammunition, (figure 3), which no other weapon has been able to do up to now. The development of GAMA effectively demonstrates the competent interaction accomplished through simulation and testing.

 

 

2.1 Research for a multiple calibre rapid firing weapon systems

An information specialist from the Council for Industrial and Scientific Research (CSIR) was subcontracted as an independent researcher to assist in the scrutinisation and exploring of papers and electronic media for the possible existence of a multi calibre rapid firing weapon system as well as the development thereof by means of simulation and testing. International academic, inter-disciplinary, military and patent databases were covered. Local and international dissertation databases were also searched. Subsequent publications of the work covered by this dissertation ensured that the successes of the GAMA project have been disseminated throughout the world. The GAMA has already being promoted and discussed in not less than sixteen local and international publications.^c

2.2 Existing development methods

The competitive market for weapons abroad has evolved a traditional design philosophy which has contributed to the successes obtained in the past. System engineering by describes the process that will ensure success illuminating risks that manifest themselves unexpectedly as unknowns that were not previously catered for. The knowledge of risks reduces the negative results with respect to the progress and performance of a project. This has served to stultify any experimentation into the direction of simulation as a design process. Currently, the identification of risks depends greatly on testing and not enough emphasis is placed on simulation, which, if used, would identify and eradicate these risks well in advance.

2.3 Available design and simulation approaches

2.3.1 Finite element analysis

Finite element analysis (FEA) enables the engineer to accurately identify stress distributions, reaction forces and structural deformations. The theoretical evaluation of a structure or components with regard to their modal behaviour, frequencies and shapes is also easily attained.

2.3.2 Motion analysis

Any mechanical system with various masses can be mathematically assembled using predefined interfaces, such as couplings, cams, slots, springs etc. A simulation model can then be used for the accurate evaluation and optimisation of the dynamic and kinematic behaviour of the system.

2.3.3 Conclusion

Although it is known that FEA, motion analysis and experimental testing are powerful tools when utilized independently, when used interactively, a superb foundation for simulation is offered. Simulation model can now be used to evaluate the modular designs with respect to the structural behaviour of a system, its dynamical response and the control algorithm. Flexible bodies can also form part of the dynamic solution of the system. System control algorithms which interface with Matlab can also form part of the design and optimisation. This method of design not only allows the engineer to alter design variables, it also facilitate in the calibration of models before they are used as a blueprint for the development of systems. Once this design is successfully evaluated, the prototypes can be manufactured. The development of GAMA was carried out using the aforementioned simulation and test philosophy.

 

3. Characterizing the Baseline Weapon System

Before any simulation model can be designed, a full understanding of typical hardware behaviour is essential. It is no use performing a numerical exercise when the theory and the practice do not conform to each other. It also helps the developmental engineer, in that it prevents him simulating in the finest detail something that cannot always be verified. This culminates in unnecessary time consumption on trivial issues that really do not have any effect on the performance of the hardware.

3.1 Description of the weapon

The MG151 was developed by the Germans in 1935 as an aircraft gun⁹. Originally it was a 15 mm weapon, but after experiencing problems it was increased to 20 mm¹⁰. The MG 151 cannon, firing percussion type primer ammunition, was later manufactured as a GA1 by DLS L, which is the main developer and manufacturer of small, medium and large calibre weapons for the SANDF¹¹. The GA1 weapon, firing 20 x 82 mm ammunition^d, was mainly utilized on the Allouette gun ship helicopters and later deployed on infantry and naval combat vehicles. These helicopters were in the process of being replaced by Augusta helicopters which at the time, were being proposed to be equipped with a GAMA weapon system. The GA1 was chosen as the baseline weapon for the development of GAMA.

The terminal effect at a target depends on the type of ammunition being fired. The projectile, which is spun by the rifling in the barrel, ensures adequate stability of the projectile during launch, also arming the nose and base fuses of the projectiles that contain explosive charges, as seen in figure 4.

 

 

Figure 5 illustrates the various types of rounds typically utilised during operations, training and development. High pressure proof and reference rounds are used during the proof and commissioning of systems.

 

 

3.2 Functionality of the weapon

Manual cocking of the GA1 weapon is obtained by pulling the cocking T-handle at the back of the cover. Cocking the weapon drives the first round against the cartridge stop. Translational movement of the spring retainer compresses the recoil spring, which moves the breech assembly backwards, positioning the breech assembly firmly against the back of the sear from where the firing of the first round commences.

During firing, the build up in pressure caused by the burning propellant launches the projectile along the rifling of the barrel. Simultaneously the counter reaction forces the interlocked barrel, the receiver bushing and the breech mechanism backwards cycling the weapon upon firing each consecutive round. The empty cartridge case remains firm against the bullet face and is only discarded when the bolt head passes below the rear end of the feed tray. The feed tray ejector pushes against the breech bolt head cartridge ejector. A downward hinged action of the cartridge ejector pushes down the cartridge case to hinge downwards over the extractor, ejecting it through the lower opening in the gun¹².

3.3 Testing of the baseline weapon

During the testing process, data was captured using sophisticated transducers. The equipment was always kept at optimum performance levels, by ensuring that it was regularly maintained and calibrated. By this means the integrity of data was kept at a level of credence that justified the confidence that was eventually put into it. Sufficient measurements (figure 6) were always taken to enable the exploration of the true behaviour of the weapon of which results is to be usable within the simulation environment.

 

 

It is important to ensure that all data acquisition measuring equipment has adequate capacity for sensing the intended behaviour of the weapon. Besides the sampling frequency of the data acquisition system and channel saturation, the frequency response of all the equipment used must be adequate to ensure that no data is lost. Cognisance of any phase shift between recorded channels was also being taken, especially when exploration of weapon behaviour was examined by overlaying recorded channels.

3.4 Results

Data was captured during live firing of 20 x 82 mm PRAC ammunition¹⁴. Captured data was analysed using signal processing software. A chronograph was used to measure the muzzle velocity. Target data was obtained for reference purposes. These results could be used to compare dispersion and mean point of impact (MPI) measurements with the new GAMA design that was to follow. Projectile yawing patterns and the blasting profile around the weapon was also measured.

3.5 Conclusion

Many tests were performed and various methods used to obtain data. Cross correlation between these tests results proved to be useful. From time to time retests were performed to verify certain scenarios that were required by the simulation process. These also confirmed that the data used in the model was reliable.

 

4. Simulating the Baseline Weapon

The base line weapon system was simulated using structural and dynamic simulation packages. A full understanding of the hardware motion behaviour pattern of this weapon in the finest detail was essential before commencing with the generation of the simulation models^{14, 15}.

4.1 Simulation models

Virtual reality is the simulation of the weapon hardware within a defined environment. The constraints for each component not only define the degrees of freedom encountered, but also relate to relative interfaces of components with each other. Interface definition was very important as it ensured that the correct sequential flow of events was catered for.

The simulation of the base line weapon laid the foundation for the development of the new rapid fire multi calibre weapon system. The proper definition of structural and motion models for the GA1 would result in a reduction in time when developing GAMA later.

The weapon hardware was constructed using the latest three dimensional computer aided design (CAD) software with computer aided manufacturing (CAM) interfaces. Variable dimensions were effortlessly accommodated using the philosophy of parametric design. The weapon was drawn in intricate detail. This enabled both the analysis, as well as the later automatic production of components using existing CAD/CAM interfaces. Rapid prototyping of components was possible using computer numerically controlled (CNC) machines. This also allowed for any design changes that were still deemed to be necessary.

It became evident that the development of a project such as GAMA, by means of simulation, would not be possible without a three dimensional data-pack in electronic format. The data-pack formed the basis of the simulation process which progressively advanced from the GA1 stage through to GAMA. On completion, the electronic data pack was exported to the FEA and motion analysis (MA) software packages. Besides analysing major / critical components, FEA and MA results were used to identify the need for analysing additional interfacing components.

Simulating the total weapon's motion behaviour was only possible by breaking it up into various modules. Each module represented a specific phase in the total firing cycle of the weapon. Checkpoints in the models were introduced to ensure numerical stability. At the time, it was not possible to set up a motion model that could run continuously throughout a complete firing cycle. The initial conditions for each consecutive phase were therefore defined from data obtained from the previous phase. Test data was also used extensively to verify the definition and the initiation of each consecutive phase.

4.2 Structural analysis

The processes involved in FEA are repetitive, and for this reason only the circumstances surrounding special cases arising out of the development will be emphasised.

Although the intrinsic detail incorporated in CAD is necessary for manufacturing, it is not always essential for the analytical process. It is therefore at times important to suppress trivial details since these generally only serve to increase the complexity of the analysis, without having any real effect on the results being obtained. On the other hand, detail such as sharp edges and corners could result in stress concentration which needed to be explored and properly analysed. The complexities of the models increased or decreased dependant on the intrinsic detail that was included or omitted. This was an iterative process that was based on experience which served to fast-track the process.

In addition, the complexity of detail within CAD models is also directly related to the type, the size and order of the elements used. The total number of nodes, and the degrees of freedom of each node, dictated the size of the simulation model. Initially the CAD model geometry has to be properly prepared and manipulated. This is followed by meshing the geometry, using various types of elements. Overlaying nodes are merged in a proper manner to ensure that continuity is correctly managed. The technique of constraining the model at various surface and edges was employed to ensure that the behavioural pattern of hardware was correctly simulated.

Analysis of all the critical components was essential, as stresses within these components were to be used as reference during the subsequent development of the GAMA.

Before any analysis could commence, it was necessary to obtain crucial 20 x 82 mm ammunition pressure test data from PMP. This is the pressure that is generated by the burning propellant during the firing of the rounds, as measured against time. The proof pressure profile is used as a design driver when analysing the structural and dynamic behaviour of the weapon with respect to safety. Before a system is certified safe for use, the firing of high pressure proof rounds is compulsory. The standard ammunition pressure profile, on the other hand, is used to characterize the normal dynamic behaviour of the weapon.

The pressure distribution along the barrel is calculated as a function of the pressure generated by the burning propellant and the projectile's dynamic behaviour inside the barrel. A polynomial fit was used to smooth the results obtained for the shot travel along the barrel and the maximum pressure was applied to the barrel chamber. The total barrel design, with the inclusion of the muzzle brake and supportive interface structures, was used when evaluating the barrel frequency.

4.3 Motion analysis

MA was performed in parallel with FEA. The motion results obtained, represented the dynamic behaviour of the weapon. This had an impact on the forces being induced in the weapon structure which were analysed using FEA. The interactive, but independent, usage of FEA and MA software resulted in the overall evaluation of the GA1 weapon. Correlation checks with physical measurements were carried out to improve the integrity of the simulation models.

CAD models of the various components were imported and displayed within the motion analysis package. The motion models were initiated by driving the breech backwards with a force which is representative of the pressure available as a result of the burning propellant. All forces representing the chamber pressure, springs, buffers and dampers were applied to user defined points on the various components and environmental structures of the model.

During motion analysis, the main objective was to calibrate the dynamic behaviour of the weapon against the physical hardware performance. Only when this behavioural pattern coincided with the hardware behaviour, could it be said that the motion models were a true representation for it to be used for the development of GAMA.

The main objective was therefore to produce a simulation model, with a reduction in complexity providing easy access and alteration capabilities for developmental purposes, while still representing the hardware performance in its present format. Simulation results proved to be closely related to the hardware performance.

4.4 Comparing test and simulation results

When comparing the test and simulated results the following minimum deviations were acknowledged:-

• Ignition @ 0,0 ms (Starting - Reference)

• Rate of fire =0,00% Goal

• Time to reach max breech travel = 2,90 %

• Max. breech travel =0,07%

• Max. buffer compression = 2,60 %

• Max. buffer recoil force =0,30%

• Time for breech to reach sear = 2,70 %

• Von Mises stress in receiver =5,20%

 

5. Development of the New Weapon System

5.1 Analysis and design

The new requirements and constraints provided in the final specification dictated the design of GAMA with respect to its fit, form and function. Maximum recoil force, travel and overall mass were kept to a minimum, with the specified firing rate of the various types of rounds being the design driver.

Geometrical, the overall length of a round dictated the ammunition feed interface of the weapon. The lower surface and rim of the cartridge case interfaced with the bolt head bullet face, the extractor and the ejector. The shape and size of the barrel chamber, together with the bolt's bullet face position, was determined by the cartridge case. This ensured that the head-space was correctly managed. The correct head space for each type of round is a function of the ramming action of the round into the barrel chamber, after which the chamber is locked prior to ignition. Two important parameters are therefore headspace and firing pin protrusion.

The longest round in the series (which was the 20 × 110 mm round) determined the total length (geometrical properties) of the weapon. This was used as the starting point of the development of the GAMA. All the motion control parameters were based on the new absolute and relative positions of the breech bolt mechanism group, ammunition feed system group, recoil mechanism group, barrel group and the receiver group.

The performance properties of the weapon, however, were determined by the ammunition with the most severe pressure profile. This was the 20 × 102 mm round. Consequently this dictated the development of the breech buffer, breech bolt mechanism group, receiver bushing, unlocking ring, barrels, springs, buffers and recoil mechanisms.

In order to design other support components, such as the feed tray, the cartridge stop, the cover hinge, spacers, and the cartridge ramp (see figure 7) the use of simulation was not necessary. Basic calculations, good gut feel and engineering common sense, together with experimental methods, were used. Future expansion of GAMA with the incorporation of additional types of ammunition is possible utilising contemporary simulation packages.

 

 

Recoil forces obtained from the simulation models enabled the design of a new composite buffer. The stress levels in the breech bolt head and receiver bushing of the GA1 locking configuration was of an unacceptable level when firing the new range of ammunition.

Simulation steered the design towards a novel concept whereby the locking of the chamber was accomplished by increasing the rotational angle of the breech bolt head inside the receiver bushing. In addition, an alternative material, capable of sustaining very high loads, was introduced. The increase of the rotational angle of the breech bolt expanded the contact area, thus resulting in a reduction in the stress loads. The conventional case hardened material was replaced by SK002 material which was subjected to an electro slag re-melting (ESR) process. (SK002 conforms to the GAMA's designed stress level requirements).

Subsequently, improved cam surfaces on both the receiver bushing and the unlocking ring were introduced to cater for the increase in the breech bolt head's rotational angle. The cam surfaces on the unlocking ring were designed to drive the bolt head anti clockwise through 90°, opening the chamber, while sustaining the forces generated by the rearwards motion of the barrel, receiver bushing, and breech bolt mechanism group. In addition to the material change (SK002), the contact area between the unlocking ring cam surfaces and the breech bolt head rollers were optimised to facilitate a reduction in loadings.

Up to this point, the use of percussion primed ammunition was described. However, the 20 × 102mm ammunition is equipped with electrical type primers and therefore a new method of activating the ammunition was introduced. This enabled the GAMA to handle both types of ammunition. The GAMA was fitted with an electrical circuit designed to control the weapon remotely from a weapon control console. A multi core harness was used as an interface between the weapon and its control console. The trigger button dually controls the supply to the trigger solenoid and an electrical charge through to the electrical firing pin.

The design of the electrical firing pin, particularly its insulation requirements towards its surrounding structure during motion, proved to be a challenge. The CSIR was approached to assist in this matter. This led to a suggestion of a ceramic coating process that has excellent wear resistance and dielectrical strength capabilities. This coating was applied using a Metco Flame Spray Process¹⁶. Unfortunately, the impact loadings between the firing pin and the primer caused the ceramic coating to fail in the vicinity of the bullet face. The damaged insulation caused an intermittent short circuit between live and ground. This problem was resolved when a special mould was designed for the firing pin, coating it with a mixture of Ureol6414 A &Ureol5117B.

Standard type GAI (MG151) links were used to convey ammunition from the magazines through the flexible chute to the weapon for all the types of ammunition with the exception of the 20 × 102 mm rounds. Accommodating the 20 × 102 mm rounds, a new prototype link was developed.

GA120 × 82 mm and 12,7 × 99 mm barrels could be used with the GAMA as standard items without alteration. Barrels launching 20 × 102 mm, 20 × 110 mm and 14,5 × 114 mm had to be designed to interface with the GAMA.¹⁷.

Both the 20 × 102 mm long and short barrels together with the 20 × 110 mm barrel were equipped with standard muzzle brakes. The geometrical appearance of the GAMA, when configured for the firing of the various types of ammunition, is noticeable in the appearance of the barrel.

Throughout the development of GAMA, aspects relating to the mass and natural frequencies were constantly noted. The natural frequencies of these barrels were determined to ensure that they do not coincide with the weapon's structural, control and firing rate frequencies. This would have compromised the weapon's accuracy.

The product baseline for the GAMA, enables the firing percussion type ammunition (12,7 × 99 mm; 20 × 82 mm; 14,4 × 114 mm; 20 × 110 mm)¹⁷ and electrical primed ammunition (20 × 102 mm)¹⁸.

In order to comply with good configuration control, the GAMA project was registered to have a unique product code. The master record index (MRI) with this product code reflects all design drawings, documentation, tooling etc. associated with the GAMA project. When GA1 MRI-items were found to be compatible with the GAMA design, these items were included as standardised items, maintaining their original product identification code. Once simulation authenticated the design of a particular component, it was released for manufacturing.

5.2 Manufacturing

The development of GAMA required both significant creative engineering development skills, as well as an equally important contribution from the operations department. Latest technology equipment, such as 4 axes CNC machines, electrical discharge machines to perform spark and wire eroding processes, were used in the manufacturing of components according to an approved GAMA concept base line¹⁹.

The challenge, however, was not only to manufacture a new GAMA, but also to prove that the old GA1 weapons hardware can be upgraded towards a GAMA status. In this case, skills, tools and control processes required for the manufacturing of components were not enough. Metallurgical expertise was now also required to certify welding processes that were to be used to produce GAMA partially from existing GA1 weapons, (as if it was machined out of solids). No welding or subsidiary flaws could be tolerated. Non-destructive testing (NDT) inspections were performed on all hardware before being released for service. For this project, manufacturing was based on the production of low volumes of hardware.

5.3 Testing

The development of GAMA in a mechanical and electrical configuration together with the development of a 20 × 102 mm link, required that all possible technical catastrophic failures, critical issues, operational failures and interfaces were well documented. This information is given in the test and evaluation master plans^{20, 21, 22}. Many tests and demonstrations (figure 8) were conducted during the development of GAMA in its various configurations including various mounting interfaces^{23, 24}. These tests and demonstrations included i.e. the following: Mutually interdependent performance checks

 

 

□ Various mounting integration checks

□ An new and novel intelligent cradle development (soft recoil)

□ Acceptance tests for the cradle developments. This included scheduled tests on GAMA when integrated with 1ST's new chin mount for the light utility helicopter, (figure 9) and RDL's remote platform.

 

 

□ Ad-hoc evaluation requests for verification purposes. Prior to each field test or demonstration, the weapon was thoroughly examined to determine the condition of all components. Real time data acquisition, NDT methods (Dye Penetrate) together with computer aided design, high integrity structural FEA and dynamic simulation (motion) packages, were used interactively during development tests. The advantage of this was that theoretically motivated changes could be predicted, immediately physically implemented and evaluated on site.

Although dye penetrate was used on the test site, a more intense NDT crack tests was performed using a Magnaflux testing unit, together with ferromagnetic particles (Tiede Fluoflux). Magnetizing was performed in a longitudinal / circular / multidirectional technique. Magnaflux crack tests were performed on all major components and are compulsory for the issue of a certificate of conformance (COC), releasing the weapon for service. These tests were frequently performed throughout the development. They were conducted in accordance with ASTM E709-85, where the reference sample size was obtained from MIL-STD-105D tables I & II.

The performance evaluations of GAMA earned a significant level of trust from team members, clients and spectators.

5.4 Results

Table 1 shows an extract from the simulated and actual results of the GAMA firing 20 × 82 mm ammunition. Results were contained in many formal and informal reports that covered the achievements to date. The formal reports reflect the results that were obtained during the system identification trials of the GA1 #1138, and the GAMA development and the unique GAMA cradle development for the GAMA^{25, 26}.

 

 

An extract of the results from the aforementioned reports are also shown in table 2. Firing rate and muzzle velocity measurements of GAMA compare favourable to weapons available internationally.

 

 

5.5 Conclusion

Field tests demonstrated that all the design requirements of the GAMA weapon were successfully met over the entire range of the intended calibres. The GAMA project also successfully demonstrated that simulation and testing methodologies can be used interactively in order to minimise the building of experimental hardware, and in so doing reduce time scales and costs.

The uniqueness of the weapon and what it offered was soon acknowledged by all, which resulted in GAMA being already being promoted and discussed in not less than sixteen local and international publications, stimulated worldwide interest. Clients explored the possibility of obtaining and integrating the GAMA as part of their own inventory, covering air-, naval- and land armament platforms. The successes also stimulated spontaneous potential participation and involvement by 3rd party ammunition and platform manufacturers.

This philosophy introduces a mind shift in development engineers towards the definite use of simulation in any project that is tightly bound to cost and time constraints. Simulation opens the way for the generation and conceptualising of new ideas, and allows more options to be tested rapidly with great success.

 

References

1. Hattingh GFS, Statement By Programme Manager, ARMSCOR, 1997.

2.ARMSCOR, User Requirement Statement, August 1997.

3. SAAF, ROC for Developing LUH Turret, November 1996.

4. LIW, GAMA - Multi Calibre Project Definition, June 1997.

5. ARMSCOR, RFP For Developing LUH Turret, 28 February 1997.

6. 1ST Dynamics, Developing Specification for the LUH Turret System, January 1998.

7. GENDIN, 22 mmMC151 System Specification, October 1986. 8. ZJW, 20mm MG151 Product Specification, 28 February 1989.

9. Chinn Colonel GM USMC (retired), Machine Gun, Vol. III, Part VIII & IX, Chap. 4, A Bureau of Ordnance Publication, 1951.

10. Chinn Colonel GM USMC (retired), Machine Gun, Part V, Chap. 19, A Bureau of Ordnance Publication, 1951.

11. LIW, Gun Automatic 20 mm GA1 Illustrated Part Breakdown, 1 February 1988.

12. Rheinmetall, Handbook on Weaponry, Düsseldorf, February 1982.

13. Van Heerden A, GAMA Mathematical Simulation: Motion Analysis and Finite Element Analysis, 28 February 1998.

14. Van Heerden A, Weapon System Failure, Report GA1, No. 1087, 21 May 1997.

15. Van Heerden A, Weapon System Failure, Report GA1, No. 1020, 10 May 2000.

16. Technical Bulletin 10-095, Metco® 105SFP Aluminium Oxide Powder, SULZER METCO, October 2000, superseded June 1983.

17. Vektor, Bill of Material for GAMA Mechanical Concept Technology Carrier, 15 January 1998.

18. Vektor, Bill of Material for GAMA Electrical Concept Technology Carrier, 15 January 1998.

19. Van Heerden A, GAMA Weapon System Concept Baseline Recommendation, 20 February 1998.

20. Van Heerden A, Test and Evaluation Master Plan for the GAMA Electrical Weapon System, 21 January 1998.

21. Van Heerden A, Test and Evaluation Master Plan for the GAMA Electrical Weapon System, 21 January 1998.

22. Vektor, 20 x 102 Link Test and Evaluation Master Plan, 20 January 1998.

23. Van Heerden A, Test Specification: Development of GAMA Weapon System, 16 January 1998.

24. Van Heerden A, 12.7 mm Dual Kit Acceptance Specification for GA1 and GAMA Weapon Systems, 13 February 1998.

25. Van Heerden A, Test Report GAMA Weapon System, 20 February 1998.

26. Van Heerden A, Demonstration TestReport: GAMA Weapon System status, 15 February 1999.

 

 

Received 25 April 2006
Revised form 19 February 2007
Accepted 9 May 2007

 

 

b Vektor was previously a business unit of LIW which again merged during April 2005 to become Denel Land Systems Lyttelton (DSL L).
c (A) Media Release DENEL (Pty) Ltd, 17 November 1998; (B) Pretoria News Friday, 20 November 1998; (C) IDEX '99; (D) ARMADA International 1/99; (E) Jane's Defence Upgrade Vol II No.21, 1-15 November 1998; (F) Jane's Defence Weekly, 25 November 1998; (G) Jane's Defence Upgrade Vol II No. 24, 16-31 December 1998; (H) Soldiers Fortune, February 1999; (I) Beeld, Tuesday 27 April 1999 - SANDF Annexure; (J) Jane's Infantry Weapons Twenty Sixth Edition 2001 -2002; (K) Amendments and Additional Notes to "Rapid Fire", 17 April 2005; (L) Publication GAMA - Kulomet, Nebo Kanón (Foreign Language- Skupina bibliograficko-informaèni èinnosti Knihovny PA ÈR vydává), 1998; (M) Vernick Aviation - Land Based Air Defence Glossary; (N) Vernick Aviation - Infantry Weapons Glossary; (O) 20 mm Ammunition; (P) South Africa Automatic Cannons.2. Literature Study
d 20 x 82 mm - 20 mm calibre with 82 mm cartridge case length