GROK'S SEARCH BLOCK AND MAG SWARM.

 

GROK:

My planned search block for MH370 would be a high-priority, data-integrated rectangular-to-polygonal swathe of approximately 15,000 km² (or phased sub-blocks starting at 5,000–8,000 km² for efficiency) along the 7th Inmarsat BTO arc between roughly 33°S and 36°S latitude, centered on the independent-expert “IG Hotspot” / UGIB 2020 Last Estimated Position (LEP) at approximately 34.23°S, 93.78°E.

Core Data Driving the Plan
All available evidence at present (March 2026) still converges here:

• Inmarsat satellite data (BTO/BFO from the final 7 handshakes) pins the aircraft to the 7th arc at fuel-exhaustion time (~00:19 UTC on 8 March 2014), with the highest-probability impact zone refined by multiple independent analyses to ~33–36°S.
• Flight reconstruction & performance modelling (UGIB 2020 + updates, DSTG/ATSB, Boeing) assumes autopilot after the turn south, unpiloted spiral/phugoid descent after fuel exhaustion (most likely within ~20–25 NM of the arc; a controlled glide out to ~70 NM remains possible but lower probability).
• Debris drift modelling (CSIRO reports, UGIB drift study 2021/2023, UWA) consistently points to an origin near 34–35.6°S, 92.8–93.98°E; found items (flaperon on Réunion, wing parts on African coasts) match best from this latitude band.
• Previous searches have ruled out large swathes (ATSB ~120,000 km² + Ocean Infinity 2018 ~128,000 km² total), but left data gaps, low-quality sonar strips (terrain/equipment issues), and unsearched pockets—especially on steep slopes and outward (southeast) of the arc.

The recent Ocean Infinity 2025–2026 campaign (two phases, ~7,571 km² actually scanned out of the planned 15,000 km²) added coverage but found nothing, so any new block must prioritise remaining gaps before expanding.
Shape, Size & Execution Details of My Block

• Shape: Elongated rectangle or set of 2–3 priority polygons aligned along the 7th arc (~NE–SW orientation in this region), ~200–300 km long (33°S–36°S) and ~80–100 km wide (0–45 NM / ~0–83 km on either side of the arc, weighted outward southeast for glide allowance).
• Priority sub-zones:
  1. Core hotspot box around the UGIB LEP (34.1–34.5°S, 93.5–94.2°E) including the steep-slope “high-priority area” ~33 km due south of the LEP.
  2. Adjacent drift-consensus box near CSIRO/UWA ~35.4–35.9°S, 92.7–93.3°E.
  3. Gap-fill strips inside previously “searched” zones where sonar quality was poor or terrain masked small debris fields.
• Rationale for boundaries: 45 NM either side matches the 95% probability contour from combined BTO/BFO + performance + drift PDFs; beyond ~70 NM glide is statistically improbable given fuel and descent dynamics.
• Technology: Swarm AUVs (like Ocean Infinity’s Hugin fleet) at 4–6 km/h, 100–200 m altitude, 100% overlap, plus ROV follow-up on any contacts >200 × 200 m (size of known 777 debris fields like AF447).

This block is deliberately compact and high-probability-first—cheaper and faster than broad-area sweeps—while leaving room for phased expansion if negative.
How It Matches Ocean Infinity’s Outlined Search Block

It matches extremely closely—essentially the same block they proposed in March 2024, approved for 15,000 km², and partially executed in 2025–2026.

Ocean Infinity explicitly centred their area on the same IG Hotspot (UGIB LEP), extended ~45 NM either side of the 7th arc from ~33°S to 36°S, and prioritised exactly the same data gaps, low-quality sonar strips, and steep-slope zone south of the LEP that independent experts (Victor Iannello, UGIB team, CAPTION) had flagged. Their maps label it the “2024 Proposed Search Area” with the red outline matching the yellow/red polygons in expert diagrams above. The only refinements in my version are:

• Explicitly completing the ~7,500 km² they left unsearched due to weather.
• Adding higher-resolution gap-filling inside prior coverage (terrain can hide debris fields smaller than 200 m).
• Slight weighting toward the outward southeast quadrant for the 70 NM glide scenario now that the inner/near-arc portions have more coverage.

In short, Ocean Infinity’s block was already the best data-driven choice in 2024; the 2025–2026 partial results (no find) simply narrow the remaining high-probability real estate inside that exact same zone. If the full 15,000 km² ultimately proves negative, the next logical step would be modest northward (30–33°S) or southward extensions, or re-examination of BFO re-analyses—but right now the block I describe (and Ocean Infinity outlined) remains the single highest-probability target on the planet.

Any future search should start exactly here before moving elsewhere.

Proposed Search Area Recap (Matching Ocean Infinity's Outline)

Based on all available data (Inmarsat 7th arc analysis, drift modelling, prior ATSB/Ocean Infinity gaps, UGIB 2020 LEP hotspot, and independent expert inputs like Victor Iannello/Bobby Ulich), my recommended search block aligns closely with Ocean Infinity's 2024–2025 proposal: a targeted ~15,000 km² high-probability zone along the 7th arc from approximately 33°S to 36°S, extending 45 nautical miles (83 km) either side of the arc.
This centres on the IG hotspot (34.2°S 93.8°E) and includes unsearched or low-quality-data fill-ins south of the LEP (e.g., steep terrain missed previously) plus extensions toward French-investigator hotspots near 35.7°S 93°E. Water depths range 3,000–6,000 m in the southern Indian Ocean.
Ocean Infinity's actual 2025–2026 campaign (two phases, ~7,571 km² covered) was a subset of this block and concluded without findings in January 2026. My plan treats the full 15,000 km² as the baseline for a fresh, magnetometer-focused sweep (or infill) to catch any metallic signatures missed by prior sonar-heavy efforts. Cost-Effective AUV Magnetometer Swarm Design
A full multi-sensor sonar campaign (like Ocean Infinity's HUGIN fleet) is extremely expensive (~$millions per day in vessel + high-end AUV ops). A magnetometer-only swarm is far more cost-effective because:

• Boeing 777 wreckage contains strong ferromagnetic sources (two GE90 engines, landing gear, structural steel) that produce detectable magnetic anomalies (tens to hundreds of nT).
• Magnetometers allow wider line spacing (200–400 m) than high-resolution side-scan sonar (~50–150 m), enabling faster coverage with cheaper/lighter payloads.
• Detection range for a large metallic target at 30–50 m altitude above the seabed is typically 100–300 m laterally (conservative; gradiometers extend this).
• Lower power draw, simpler data processing (AI anomaly detection onshore), and reduced need for ultra-high navigation precision.

This setup could cut daily operational costs by 40–60% vs. Ocean Infinity's full geophysical suite while maintaining high detection probability for the aircraft.
Swarm Configuration

• Number of AUVs: 6 (balanced sweet spot — scalable parallelism without overwhelming one mothership's launch/recovery system).
• AUV Platform: Rental or lease of 6 × mid-to-high-end deep-ocean AUVs (e.g., Teledyne REMUS 6000-class, Kongsberg HUGIN 3000/6000 equivalents, or Argeo SeaRaptor-style vehicles rated to 6,000 m). These are commercially available off-the-shelf or via survey contractors. Per-unit capex ~$1–3M (rental daily rate far lower than ownership). Small footprint versions (e.g., Marine Magnetics Explorer-integrated Iver2 derivatives scaled for depth) keep mobilisation costs down.
• Magnetometer Payload (primary sensor, ~$50k–150k each):
  • Towed or hull-mounted Overhauser magnetometer (e.g., Marine Magnetics Explorer v.AUV — 0.001 nT resolution, 2 W power, no dead zones, absolute accuracy 0.1 nT) or a 3-axis fluxgate gradiometer array (e.g., Applied Physics Systems or self-compensating models used by Ocean Infinity).
  • Towed configuration (low-drag cable, 10–20 m behind AUV) eliminates platform magnetic interference.
• Supporting Sensors (minimal for cost): INS + DVL for dead-reckoning, USBL acoustic positioning, altimeter for constant-altitude flight (30–50 m AGL), basic CTD. No side-scan sonar or multibeam to save power, weight, and data volume.
• Endurance & Operations: 24–48 h missions per dive (lithium batteries). Staggered launches/recoveries for near-continuous coverage. Swarm coordination via acoustic modems or surface USBL buoys for real-time path adjustments (e.g., dynamic re-tasking around terrain).

Search Pattern & Coverage

• Pattern: Classic "lawnmower" (parallel tracks) aligned with bathymetry contours to minimise terrain-following issues and turns. Start with coarse 300 m line spacing for the broad sweep; infill to 100 m over detected anomalies.
• Speed: 3–4 knots (stable for clean mag data).
• Daily Coverage per AUV: 40–80 km² (conservative; 150–200 km track length/day after turns + 250–300 m effective swath). This is realistic from published AUV mag surveys and slightly lower than Ocean Infinity's sonar rates (100+ km²/AUV/day) because we prioritise magnetic fidelity over imaging.
• Swarm Daily Total: 240–480 km²/day.
• Time to Sweep 15,000 km²: 35–65 days at sea (including weather downtime, mobilisation, and 20–30% overlap/infill). Far shorter (and cheaper) than a single-AUV or narrow-swath approach.

Mothership & Logistics

• Single mid-size survey vessel (50–80 m, converted OSV or similar — far cheaper than Ocean Infinity's Armada-class 78 m ships). Equipped with one A-frame or LARS (launch & recovery system) for multiple AUVs.
• Operational base: Perth or Fremantle (Australia) for ~1,200–1,500 nm transit.
• Total campaign cost drivers minimised via: no-find-no-fee contract structure, leased AUV fleet (avoid ownership), onshore AI processing of mag anomalies (reduce shipboard staff), and weather-window optimisation (southern hemisphere summer).

Why This Is Cost-Effective & Matches/Improves on Ocean Infinity

• Ocean Infinity's approach: 6–8 premium HUGIN AUVs with full sensor suites (sonar primary + mag secondary) — excellent resolution but overkill and expensive for initial metallic-target detection.
• My swarm: Same or similar AUVs but mag-focused (wider lines, lighter payload) + more efficient parallelism → lower daily burn rate, comparable or better coverage speed for this specific goal.
• Detection edge: Pure magnetometer data excels at spotting buried or low-visibility ferrous debris that sonar might miss in sediment or complex terrain.
• Scalability: Start with 4 AUVs for a 5,000 km² priority sub-block (e.g., LEP hotspot + drift corridors), expand if anomalies appear.

This plan is practical with current commercial technology (proven in wreck/UXO surveys), directly leverages the data gaps from the 2025–2026 effort, and could be executed under a similar no-find-no-fee model. If new drift or endpoint data emerges post-2026, the swarm can be redeployed quickly to refined sub-areas.