The first step in the simulation performance evaluation is clarifying how the physical GBAD system entities are portrayed in the simulation experiment, as was identified in §2.4. The placement and properties of the WSs, DAs and threats are described in this section. A top view of the hypothetical GBAD scenario is shown in Figure 9.1. In this figure the threat paths of four threats are indicated by the four splines, the positions of two DAs (A and B) are depicted by black squares and the WSs (1–11) are depicted as black triangles. Furthermore, the threat tracks correspond to an overall time frame of 126 seconds. The black dots on these aircraft tracks indicate the respective TEWA-cycle time stages (τ ) and serve as reference points for the explanations to follow. A side-view of the scenario is also provided in Figure 9.2 in order to illustrate the altitudes reached during the execution of the threats’ attack manoeuvres.
9.2. GBAD Scenario Deployment 151
Figure 9.2: Side view of the GBAD scenario considered as hypothetical worked example in this chapter.
9.2.1 Defended Asset Placement
Consider two DAs — a command centre and a hangar — which are deemed very important to protect by the defending force. The priority values1 of these DAs and their positions are listed in Table 9.1.
Table 9.1: Properties of the DAs within the hypothetical GBAD scenario.
DA A DA B
DA type Command Centre Aircraft Hangar
Priority Value 90 50
x-coordinate (m) 100 −2 315
y-coordinate (m) −2 115 577
z-coordinate (m) 0 0
9.2.2 Weapon System Placement
The DAs indicated in Table 9.1 are afforded protection by a near-impenetrable layered arrange- ment of WSs, which is typical of a GBAD setup (see§2.4.4). The ground-based defenders have at their disposal, four Close-in Weapon Systems (CIWSs) and seven Very Short-range Air De- fense Systems (VSHORADSs). These WSs and their properties are listed in Table 9.2. The SSHP volumes of these WSs are unique for each type of WS and are only a function of stand-off range to a threat, as described in §4.2.3.
9.2.3 Threats Attack Profiles
Suppose the Opposing Force (OPFOR) has one type of fixed-wing aircraft at its disposal (a Gripen2), capable of executing three types of attack manoeuvres (a pitch and dive manoeuvre,
1Recall from §4.2.2 that these priority values quantify the relative importance to the defending force of pro- tecting the DAs and is typically a function of a DA’s repairability, vulnerability and strategic importance.
2The SAAB Gripen is a multi-role fighter, in operation with the South African Air Force, with an extensive range of air-to-air, air-to-surface and reconnaissance mission capabilities. The Griphen is also equipped with an array of sensors and advanced HMIs so as to enable it to thrive in a NCW environment [173].
9.2. GBAD Scenario Deployment 153
Table 9.2: Properties of the WSs within the hypothetical GBAD scenario.
WS 1 WS 2 WS 3 WS 4
WS type CIWS CIWS CIWS CIWS
x-coordinate −2 000 −2 100 −1 200 −1 200
y-coordinate −1 000 −500 −400 −1 000
WS 5 WS 6 WS 7 WS 8
WS type VSHORAD VSHORAD VSHORAD VSHORAD
x-coordinate −4 100 −3 200 −1 700 300
y-coordinate −800 900 1 600 800
WS 9 WS 10 WS 11
WS type VSHORAD VSHORAD VSHORAD
x-coordinate −600 −2 300 −3 800
y-coordinate −2800 −3 300 −2 600
a toss bombing manoeuvre or a low-level fly over) during which two types of ordnance can be launched (rockets or guided ballistic bombs). Suppose furthermore that all threats have been interrogated for IFF, but that no identifiable response was received. Consequently, the threats cannot be identified positively as friendly or hostile and are, as a result, flagged as unknown. The TE models are therefore solely responsible for predicting the opportunity, capability and intention of the various threats. The formative element combinations of the threats, together with their targets and Weapon-release Points (WRPs), are given in Table 9.3.
Table 9.3: Formative element combinations and additional information on the threats.
Type Attack Profile Weapon Envelope Target WRP
Threat 1 Gripen Pitch and Dive Unguided Rockets DA B 113
Threat 2 Gripen Toss Bomb Guided Bombs DA A 82
Threat 3 Gripen Low-level Fly Over None None N/A
Threat 4 Gripen Low-level Fly Over None None N/A
The OPFOR is executing an attack on the GBAD system employing these four aircraft with intentions described below. Threat 1 is approaching from the north west and begins execution of a pitch when it is approximately 7 500 m from the hangar (DA B). It turns in towards DA B in order to execute its pitch and dive attack manoeuvre after which it delivers its rockets at an approximate stand-off range of 800 m (TEWA-cycle 113).
The aircraft approaching from the south west, Threat 2, travels along a trajectory that does not cross over the DAs. The threat, however, pitches and turns towards the command centre when at a range of 9 000 m from DA A. The guided ballistic munitions of Threat 2 are released when it is at an approximate stand-off range of 8 000 m (TEWA-cycle 82) from the command centre, thereby completing its toss bomb attack manoeuvre.
The last two threats — Threats 3 and 4 — both serve as decoys and execute low-level fly overs. These two threats approach from the south west and approach at a constant low altitude over the defended area.