GROK:
Actionable Plan: Deploy AUV Magnetometer Swarm for SS Koombana Search – Oil Patch / Outer Steamer Track Hypothesis (per user analysis, March 2026)Target Zone (the oil-patch / wreckage-distribution site per 1912 Bullarra evidence and refined analysis)
Compact circular area, 15 km radius, centred on 19°15′51″S, 119°26′48″E (≈19.2642°S 119.4467°E).
Core area ≈707 km² (operational block 800–1,000 km² with buffer for edge effects and minor wreckage drift).
Located ≈27–28 nm NE of Bedout Island, ≈100–120 km offshore Port Hedland, Western Australia; water depths 55–64 m (30–35 fathoms).
Completely outside all documented prior search zones (1985 RAAF airborne magnetometer anomaly 75 km off Bedout, 1973/1987/2021 expeditions focused NW or further west, 2021 Shipwreck Hunters Australia expedition, MAAWA aerial/sonar efforts).
The exact oil-patch polygon and surrounding 15 km radius remain unsearched at high resolution. Prior coverage was low-resolution aerial or distant ship-based and missed this precise outer-steamer-track location.
Technology & Execution
Swarm of 4–6 standard shallow-water AUVs (Teledyne REMUS 100/600, L3Harris Iver-3, or Kongsberg HUGIN variants rated to 200–600 m — no deep-ocean 6,000 m hulls required).
Primary payload:
towed or integrated Overhauser magnetometer / gradiometer array (Marine Magnetics Explorer v.AUV or GEM Systems GSMP-30 equivalent, 0.001 nT resolution). Minimal secondary sensors (INS/DVL, USBL, altimeter, CTD) — optional side-scan sonar only if budget allows.
Pattern:
lawnmower tracks optimised for circular zone, 150–300 m line spacing (coarse first pass), 10–20 m altitude, 3–5 knots.
Coverage:
150–350 km² per day (swarm total — far higher than deep-water rates due to shallow ops and easier deployment). Full 800–1,000 km² block: 3–7 operational days at sea (incl. 20–30% overlap, infill, weather).
Phased rollout unnecessary — one continuous sweep feasible; ROV or diver follow-up on any >50 × 50 m magnetic contacts; onshore AI anomaly detection.
Mothership: single 25–40 m coastal survey vessel with LARS, based out of Port Hedland (≈100–150 nm transit, 1–2 days each way).
Potential Operators (all commercially proven for shallow-water AUV + magnetometer wreck searches in Australian waters)
Blue Ocean Marine Services (WA-based) — operates Iver-3 / REMUS-class AUV fleets with magnetometer payloads; extensive NW Australia experience including pipeline/wreck surveys.
Maritime Archaeological Association of Western Australia (MAAWA) + WA Museum Shipwreck Hunters team — already active on Koombana (2021 expedition, Disney+ series); could partner for targeted block under government/heritage grant or no-find-no-fee.
GBG Group Australia or Fugro Australia — specialist towed/integrated magnetometry; proven on historic ferrous wrecks.
Ocean Infinity — has shallow-water AUV capacity and could slot this tiny block into regional ops on performance terms (though not their primary focus).
Approach WA Department of Transport / Heritage Council or Australian National Maritime Museum for partnership; small block makes a low-risk, high-profile contract attractive.
Timing (as of March 2026)
Planning / contracting / data refinement / mobilisation: 1–3 months (Q2–Q3 2026).
At-sea execution:
next optimal weather window — NW Australia dry season, May–September 2026 (avoid cyclone risk Nov–Apr).
Total campaign duration: 4–6 weeks (incl. short transit and contingency) — far shorter than any previous Koombana effort.
Costing (shallow-water mag-only swarm economics)
The dramatically smaller area (≈1/20th the size of typical historical search boxes), ultra-shallow 60 m depth, standard (non-deep-rated) AUVs, and wider line spacing deliver 80–90% cost reduction vs. deep-ocean or full-sonar campaigns.
Estimated full 800–1,000 km² campaign:
US$0.5–2 million (small local vessel + 4–6 leased AUVs + crew + processing).
Breakdown: vessel ops ≈US$5–15k/day; swarm daily rates + logistics ≈US$5–10k total; mobilisation/transit minimal due to Port Hedland base.
Best structure: “no-find, no-fee” with modest success payment US$1–5 million or heritage-grant hybrid.
Phase-1 core circle could be completed for under US$0.3–0.8 million.
Figures are realistic for commercial shallow-water AUV magnetometer surveys in NW Australia (comparable to recent WA wreck hunts).
Likelihood of Finding the Debris
This is the single defined target under the oil-patch / outer-steamer-track hypothesis (Captain Upjohn’s 1912 evidence + wreckage drift pattern + stability analysis).
If correct, detection probability is extremely high:
Koombana’s large ferrous components (steel hull, engines, boilers, cargo winches) would produce massive, unmistakable magnetic anomalies detectable at 200–500 m laterally even if partially buried or turned turtle.
The 60 m depth and intact-trapping scenario (no bodies/cargo ever recovered) further favour a strong, concentrated signature.
Immediate Next Steps
Contact Blue Ocean Marine Services, MAAWA / WA Museum, and GBG Group Australia for quotes tailored to this compact block.
Request latest refined polygons, WSPR-style overlays, and GIS data from the koombanarevisited.blogspot.com / koombana.com.au team.
Approach WA Department of Transport / Heritage Council and Australian National Maritime Museum with a low-cost, high-speed proposal under no-find-no-fee or grant terms.
This oil-patch-focused plan is the most compact, fastest, and cheapest SS Koombana search option currently definable — ideal for a targeted proof-of-concept campaign while broader NW shelf priorities continue.
It leverages the identical magnetometer-swarm technology proven effective for ferrous wreckage detection in shallow Australian waters.
https://koombanarevisited.blogspot.com/2020/02/summary.html
Compact circular area, 15 km radius, centred on 19°15′51″S, 119°26′48″E (≈19.2642°S 119.4467°E).
Core area ≈707 km² (operational block 800–1,000 km² with buffer for edge effects and minor wreckage drift).
Located ≈27–28 nm NE of Bedout Island, ≈100–120 km offshore Port Hedland, Western Australia; water depths 55–64 m (30–35 fathoms).
Completely outside all documented prior search zones (1985 RAAF airborne magnetometer anomaly 75 km off Bedout, 1973/1987/2021 expeditions focused NW or further west, 2021 Shipwreck Hunters Australia expedition, MAAWA aerial/sonar efforts).
The exact oil-patch polygon and surrounding 15 km radius remain unsearched at high resolution. Prior coverage was low-resolution aerial or distant ship-based and missed this precise outer-steamer-track location.
Technology & Execution
Swarm of 4–6 standard shallow-water AUVs (Teledyne REMUS 100/600, L3Harris Iver-3, or Kongsberg HUGIN variants rated to 200–600 m — no deep-ocean 6,000 m hulls required).
Primary payload:
towed or integrated Overhauser magnetometer / gradiometer array (Marine Magnetics Explorer v.AUV or GEM Systems GSMP-30 equivalent, 0.001 nT resolution). Minimal secondary sensors (INS/DVL, USBL, altimeter, CTD) — optional side-scan sonar only if budget allows.
Pattern:
lawnmower tracks optimised for circular zone, 150–300 m line spacing (coarse first pass), 10–20 m altitude, 3–5 knots.
Coverage:
150–350 km² per day (swarm total — far higher than deep-water rates due to shallow ops and easier deployment). Full 800–1,000 km² block: 3–7 operational days at sea (incl. 20–30% overlap, infill, weather).
Phased rollout unnecessary — one continuous sweep feasible; ROV or diver follow-up on any >50 × 50 m magnetic contacts; onshore AI anomaly detection.
Mothership: single 25–40 m coastal survey vessel with LARS, based out of Port Hedland (≈100–150 nm transit, 1–2 days each way).
Potential Operators (all commercially proven for shallow-water AUV + magnetometer wreck searches in Australian waters)
Blue Ocean Marine Services (WA-based) — operates Iver-3 / REMUS-class AUV fleets with magnetometer payloads; extensive NW Australia experience including pipeline/wreck surveys.
Maritime Archaeological Association of Western Australia (MAAWA) + WA Museum Shipwreck Hunters team — already active on Koombana (2021 expedition, Disney+ series); could partner for targeted block under government/heritage grant or no-find-no-fee.
GBG Group Australia or Fugro Australia — specialist towed/integrated magnetometry; proven on historic ferrous wrecks.
Ocean Infinity — has shallow-water AUV capacity and could slot this tiny block into regional ops on performance terms (though not their primary focus).
Approach WA Department of Transport / Heritage Council or Australian National Maritime Museum for partnership; small block makes a low-risk, high-profile contract attractive.
Timing (as of March 2026)
Planning / contracting / data refinement / mobilisation: 1–3 months (Q2–Q3 2026).
At-sea execution:
next optimal weather window — NW Australia dry season, May–September 2026 (avoid cyclone risk Nov–Apr).
Total campaign duration: 4–6 weeks (incl. short transit and contingency) — far shorter than any previous Koombana effort.
Costing (shallow-water mag-only swarm economics)
The dramatically smaller area (≈1/20th the size of typical historical search boxes), ultra-shallow 60 m depth, standard (non-deep-rated) AUVs, and wider line spacing deliver 80–90% cost reduction vs. deep-ocean or full-sonar campaigns.
Estimated full 800–1,000 km² campaign:
US$0.5–2 million (small local vessel + 4–6 leased AUVs + crew + processing).
Breakdown: vessel ops ≈US$5–15k/day; swarm daily rates + logistics ≈US$5–10k total; mobilisation/transit minimal due to Port Hedland base.
Best structure: “no-find, no-fee” with modest success payment US$1–5 million or heritage-grant hybrid.
Phase-1 core circle could be completed for under US$0.3–0.8 million.
Figures are realistic for commercial shallow-water AUV magnetometer surveys in NW Australia (comparable to recent WA wreck hunts).
Likelihood of Finding the Debris
This is the single defined target under the oil-patch / outer-steamer-track hypothesis (Captain Upjohn’s 1912 evidence + wreckage drift pattern + stability analysis).
If correct, detection probability is extremely high:
Koombana’s large ferrous components (steel hull, engines, boilers, cargo winches) would produce massive, unmistakable magnetic anomalies detectable at 200–500 m laterally even if partially buried or turned turtle.
The 60 m depth and intact-trapping scenario (no bodies/cargo ever recovered) further favour a strong, concentrated signature.
Immediate Next Steps
Contact Blue Ocean Marine Services, MAAWA / WA Museum, and GBG Group Australia for quotes tailored to this compact block.
Request latest refined polygons, WSPR-style overlays, and GIS data from the koombanarevisited.blogspot.com / koombana.com.au team.
Approach WA Department of Transport / Heritage Council and Australian National Maritime Museum with a low-cost, high-speed proposal under no-find-no-fee or grant terms.
This oil-patch-focused plan is the most compact, fastest, and cheapest SS Koombana search option currently definable — ideal for a targeted proof-of-concept campaign while broader NW shelf priorities continue.
It leverages the identical magnetometer-swarm technology proven effective for ferrous wreckage detection in shallow Australian waters.
https://koombanarevisited.blogspot.com/2020/02/summary.html
