UWILD Survey
ABS, DNV, Lloyd’s Register, and BV accredited subsea hull inspections. Eliminating commercial drydocking downtime through certified dive diagnostics.
Class compliance verified, without taking your vessel offline
AFLOAT vessel shell inspections demand absolute diagnostic accuracy. Combining 100% ADAS-accredited commercial divers with multi-echo ultrasonic sensors, galvanic reference cells, and clear-water camera feeds, CMG delivers certified UWILD audits. We verify weld integrity, clear sea chest intakes, and measure shaft drop clearances, streaming real-time metrics straight to the witness surveyor.
UWild Survey Capabilities
Certified compliance. Minimal disruption.
IACS CLASS-APPROVED AUDITS
Fully accredited by major IACS classification societies including DNV, ABS, Lloyd’s Register, Bureau Veritas, and RINA to perform high-resolution subsea hull integrity inspections in lieu of drydocking.
HULL ULTRASONIC GAUGING (UTT)
Executing non-destructive parental metal testing utilising multi-echo subsea thickness gauges. Quantifies residual steel boundary depth through organic layers without needing surface grinding.
CATHODIC POTENTIAL (CP) MAPPING
Deploying high-accuracy silver/silver-chloride (Ag/AgCl) contact probes to map electrochemical gradients along the hull, zinc anodes, and welds to isolate corrosion hotspots.
CLEARANCE & WEAR-DOWN METROLOGY
Utilising subsea dial calipers, micrometers, and tactile gauges to record rudder pintle drop clearances and propeller shaft wear-down parameters to millimetric precision tolerances.
SEA CHEST INTAKE REMEDIATION
Deploying ADAS diving crews to safely unbolt heavy sea chest intake grates, execute complete internal camera inspections, clear biological bio-fouling, and restore hydrodynamic flow.
CCTV SURFACE TELEMETRY
Streaming continuous high-definition underwater video feeds directly to surface monitors. Class surveyors and RPEQ inspectors can witness, record, and guide the dive sequence from the surface.
Structural & Metrology Framework
We remove the disconnect between physical assets and analytical diagnostics. CMG’s inspection division operates a comprehensive subsea ecosystem linking high-fidelity data acquisition to professional engineering review.
ADAS & AS 2299.1 SAFE SYSTEMS
Our commercial divers are 100% ADAS-accredited and operate surface-supplied diving systems strictly aligned with AS 2299.1:2015 safety parameters, ensuring safe operations inside active port complexes.
ADVANCED SENSOR INTEGRATION
We utilise synchronised sensor payloads—such as multi-beam imaging sonars, subsea dual-scaling lasers, and Cygnus thickness testing tools—to bypass environmental limitations like heavy turbidity.
RPEQ-CERTIFIED DIAGNOSTICS
Raw inspection logs are systematically formatted, reviewed, and approved under RPEQ frameworks, providing maritime asset owners with robust structural integrity reports.
Afloat Hull Hydrodynamics
Marine vessels operate in highly dynamic, aggressive aquatic boundaries. CMG’s afloat hull diagnostics isolate structural anomalies and coordinate metrology checks prior to drydock deployments.
HYDRODYNAMIC WEAR TOLERANCES
Evaluating rudder pintle drop clearances, gudgeon alignments, and propeller shaft wear down parameters utilising subsea dial micrometers and class-approved Poker Gauges.
ELECTROCHEMICAL MITIGATION
Isolating active galvanic corrosion hotspots along weld seams, rudders, and sea chests using high-accuracy silver/silver-chloride (Ag/AgCl) contact potential reference cells.
LOTO MECHANICAL ISOLATIONS
Coordinating strict Lock-Out/Tag-Out (LOTO) protocols with the vessel's Chief Engineer, ensuring complete pump system isolations prior to sea chest grate removal.
Frequently Asked Questions
Technical insights regarding our subsea inspection, diving standards, and diagnostic systems.
What is a UWild Survey, and why is it preferred over traditional drydocking?
Under Water Inspection in Lieu of Drydocking (UWILD) is a class-approved alternative that allows shipowners to verify the structural integrity of their vessel’s hull while it remains afloat. Traditional drydocking requires taking the vessel completely out of service, traveling to specialised dockyards, and incurring high transit and drydock fees. By deploying ADAS-certified commercial divers or ROVs to perform equivalent hull, propeller, rudder, and sea chest inspections in-water during normal port cargo operations, CMG eliminates offline operational downtime and reduces overall compliance costs.
Which classification societies approve Commercial Marine Group's UWild Survey protocols?
CMG’s subsea diagnostic procedures, personnel accreditations, and telemetry equipment are fully certified and audited by the world’s leading International Association of Classification Societies (IACS) members. We hold formal in-water survey approvals from Det Norske Veritas (DNV), the American Bureau of Shipping (ABS), Lloyd’s Register (LR), Bureau Veritas (BV), and RINA. Our surveys are routinely conducted under the direct physical or remote video supervision of local class surveyors.
How are rudder pintle and propeller shaft wear-down clearances measured underwater?
Measuring drop clearances underwater requires high-precision mechanical metrology. To measure rudder pintle clearances, ADAS divers use custom-machined brass feeder gauges, dial indicators, or subsea vernier calipers to record the specific physical gap between the pintle shaft and the gudgeon bushing. For propeller shaft wear-down, we utilise specialised Poker Gauges inserted into class-specified reading ports, mapping the mechanical displacement to the micrometre level. These measurements are cross-checked against the vessel’s original baseline shipyard drawings to confirm they fall within maximum allowable class wear tolerances.
What steps are taken to perform safe inspections inside restricted sea chests and seawater intakes?
Intake and sea chest inspections present significant hazards due to confined space conditions and the danger of active ship suction pump systems. In strict compliance with AS 2299.1:2015 safety parameters, CMG implements rigid Lock-Out/Tag-Out (LOTO) procedures with the vessel’s Chief Engineer before any diver enters the water. All relevant suction and discharge pumps are physically isolated, electronically locked out, and tagged. Once safe isolation is confirmed, ADAS divers unbolt the external protective grates to perform visual camera sweeps, ultrasonic metal testing, and bio-fouling removal.
How do CMG manage underwater visual clarity in highly turbid commercial port environments?
In turbidity-heavy ports such as the Brisbane River or Fremantle Inner Harbour, underwater visibility is often less than 0.5 metres. To ensure classification surveyors can inspect steel plating and welds confidently, CMG uses high-frequency multi-beam imaging sonars (such as Oculus arrays) to construct acoustic 2D profile grids through suspended silt. For critical close-up visual inspections, we employ clear-water displacement chambers fitted directly onto our high-definition cameras, expelling turbid sediment and allowing surveyors to inspect key areas with absolute visual clarity.