Analysis of the capability matrix — mapping which work groups perform which standard jobs — reveals a clear tiered structure across the 44 active work groups. This has direct implications for schedule optimisation, as it determines which groups can realistically absorb work from others.
| Tier | Groups | Jobs per group | Description |
|---|---|---|---|
| Full capability | 18 | 30-43 | General-purpose signals sections. Can perform virtually any standard job. |
| Broad | 15 | 20-29 | Most signals sections. Nearly full capability with some gaps. |
| Moderate | 3 | 10-19 | Reduced scope — Dandenong 4303/4304 and Caulfield Loop. |
| Narrow | 5 | 4-9 | Loop sections (Burnley, City Circle, Northern), CBCT Group, Interlocking 6201. |
| Specialist | 3 | 1-3 | Technical Support, Maintenance Support OIC, Spencer Street 1102. |
The 33 groups in the Full and Broad tiers represent the core workforce. They are largely interchangeable for common maintenance tasks and are the primary candidates for schedule optimisation.
13 standard jobs are performed by 25 or more of the regular signals sections, accounting for 53% of all work orders (8,747 of 16,575):
| Job | Groups | WOs | Task |
|---|---|---|---|
| SP209 | 35 | 1,693 | Enclosure inspection & clean |
| SP311 | 35 | 1,455 | Trainstop inspection (Hydraulic JAH Mk1) |
| SP327 | 30 | 1,212 | Point mechanism inspection (Electric WBS M Series) |
| SP305 | 35 | 522 | Signal inspection (Electric Searchlight K2) |
| SP368 | 27 | 577 | Train detection inspection (Jeumont) |
| SP392 | 25 | 558 | Axle counter inspection (Frauscher) |
| SP352 | 28 | 471 | Train detection inspection (Jointless CSEE UM71) |
| SP329 | 32 | 458 | Point mechanism inspection, lubricate & test |
| SP387 | 26 | 423 | Auto gate inspection |
| SP370 | 26 | 279 | Train detection |
| SP359 | 27 | 272 | Train detection |
| SP305A | 25 | 187 | Signal inspection variant |
| SP216 | 26 | 198 | Enclosure inspection, check, clean & test |
This means that for over half of all scheduled work, any team from the same depot could pick up the work from another team. This is the foundation for the consolidation opportunity.
Eight groups have been identified as specialist or narrow-scope and should be excluded from the scheduling inefficiency analysis. These groups are set up to perform specific tasks that require dedicated competencies or cover infrastructure that general signals sections do not service:
Interlocking Section 6201 (E-Gate) — 4 exclusive job types (SP207, SP217, SP357, SP363). Services interlocking and air distribution equipment at 12 locations across the network. No other group does these jobs.
CBCT Group (E-Gate) — 8 job types focused on CBTC (Communications-Based Train Control) equipment at Sunshine and Dandenong. Requires specialist CBTC competency.
Maintenance Support OIC (E-Gate) — Only performs SP209 (enclosure inspection), SP392 (axle counter), and SP803 across the network. Support/oversight role.
Loop Sections (Burnley 1402, Caulfield 1404, City Circle 1401, Northern 1403) — Dedicated to underground loop infrastructure with 4-10 job types each. Narrow scope driven by the specific equipment in the underground network.
Technical Support — Just 2 work orders (SP690). Administrative/support function.
When these groups appear at the same location as regular signals sections, it is not an inefficiency — they are performing different, specialised work that the regular sections cannot do.
Of the 313 location-day overlaps identified, 61 involve specialist groups (19%) and should be treated separately. The remaining 252 overlaps between regular signals sections represent the genuine optimisation opportunity.
The fact that 33 of 44 groups can perform 20+ job types, and that 53% of work orders are for jobs done by 25+ groups, means there are very few technical barriers to consolidating work within a depot. If two sections from the same depot are both at Dandenong doing SP311 (trainstop inspection), either team could absorb the other's work.
Dandenong Signals Section 4302 is notable for performing both regular signals work (27 job types) AND CBTC-specific jobs (SP501, SP503, SP511, SP801, SP802 — 31 WOs). This suggests some cross-training has occurred, which could be a model for reducing the CBCT Group's travel if extended.
Spencer Street Signals Section 1102 only performs 2 job types (SP322B and SP322C) with just 33 work orders, all at Southern Cross. This may indicate a team set up for a very specific piece of infrastructure rather than a general signals section.
Sections within the same depot generally have similar capability profiles. For example, Clifton Hill's three sections (3301, 3302, 3303) all perform 25-43 job types with significant overlap. This reinforces that within-depot consolidation is technically feasible.
Dandenong 4303 (14 jobs) and 4304 (17 jobs) have notably fewer job types than their depot peers 4301 (30 jobs) and 4302 (27 jobs). This could indicate newer teams still building competency, or teams deliberately assigned a narrower scope. The optimisation should account for this by not assigning jobs outside a group's demonstrated capability.