In the late 1960s, the former SADF acquired a substantial quantity of Oerlikon 35 mm anti-aircraft guns, together with radar-guided, Super Vledermaus Fire Control Units (FCU).
The FCU gives the guns a remote operation capability that allows targets to be tracked by radar and fired upon by paired guns which form a battery of eight guns in total. Over time the guns have been upgraded and the FCUs have been replaced to ensure their continued effectiveness into the 21st century.
The latest upgrades were awarded to Rheinmetall Air Defence (RAD) of Switzerland. This involved the modification of the 35 mm guns to Mk 5A and Mk 7 status, together with the supply of the latest Skyshield radar sensor units and Gun Fire Control Posts (GFCP). These now form part of the Mobile Air Defence System (MOBADS) as an element of the Ground-Based Air Defence System (GBADS), comprising the fire control elements of a locally-integrated GFCP with the primary objective of countering air threats.
The Mk 5A guns fire conventional HE (High-Explosive), HEI (High-Explosive Incendiary), HEI-T (High-Explosive Incendiary Tracer), and PRAC-T (Practice Tracer) ammunition to destroy aerial targets. The Mk 7 guns are capable of firing the latest Rheinmettal AHEAD (Advanced Hit Efficiency and Destruction) ammunition. Each AHEAD 35 mm x 228 mm airburst projectile contains a lethal payload of heavy-metal, spin-stabilised, sub-projectiles that explode at a pre-programmed point in the flight path of the approaching target – effectively producing a cloud of lethal sub-projectiles to penetrate the outer skin of the target and cause catastrophic internal damage.
Rheinmettal Air Defence appointed Sigma Logistic Solutions for the logistic support development for the upgrade of the MK 5A and Mk 7 guns, and the FCUs. To ensure full support of the system throughout its life cycle, Sigma had to prepare 41 planning documents and more than 200 logistic support documents covering the SANDF maintenance support concept of Organisation Level and Intermediate Level support, and operation within the South African environment.
Among the many Logistic Support Analysis (LSA) documents created were Physical Breakdown Structures (PBS), Functional Breakdown Structures (FBS), Failure Mode Effects and Criticality Analysis (FMECA) reports, Task Analyses and Identification reports, the definition of spares, and life cycle costings for the Mk 5A, Mk 7 guns, and the FCU.
In total, 167 operator and technical manuals were produced to the exacting RSA-MIL-STD 122. The operator publications encompassed General Information Manuals, Operator Maintenance Manuals, Registers of Equipment and Accessories, Aide Memoires, Illustrated Stock Lists, and Drill Books.
The technical manuals for use by trained technical staff covered Workshop Repair Manuals; Illustrated Parts Breakdowns; Package Handling and Storage Manuals; Preparation, Preservation and Packaging Manuals; Illustrated Stock Lists; Failure Forms; Log Books; and History Files.
For such a complex weapon system, the training of operators and support staff forms a critical element across the gun platforms and the FCU. Planning documents were developed and more than 400 training documents were produced covering Curriculums, Task Listings, Instructor Guides, Learner Guides, Assessment Guides, slide shows, and wallcharts. Sigma personnel also presented hands-on training courses held at the home of the SA Army Air Defence Artillery Formation in Kimberley. Final acceptance of the manuals and courseware is currently in progress with product system support to be on-going during the Operating Phase.