First Marine Solutions (FMS) was contracted to deliver rig entry site debris surveys across multiple North Sea locations in support of upcoming anchor installations for a semi-submersible drilling rig.
Traditionally delivered using Anchor Handling Vessels (AHV) with ROV systems or dedicated survey vessels, FMS instead deployed an Autonomous Underwater Vehicle (AUV) solution launched from a spot-hire PSV. The outcome? A fundamental shift in project economics and delivery timelines.
Scope of Work
The scope included full survey covering proposed anchor spreads, including:
- Anchor corridors and mooring lines
- Subsea infrastructure and hazards
- Seabed characterisation and debris identification
The Challenge
The client required a solution that could maintain or improve data quality while significantly reducing costs and accelerating the timeline from data acquisition to decision-making.
While traditional delivery methods are effective, they introduced several challenges to the client’s requirements:
- Substantial vessel day rates – often the largest cost component of the survey
- ROV-based operations = risk on vessel availability, which can lead to downtime / extended project duration
- Conventional workflows can delay data processing and interpretation, slowing down the delivery of actionable insights.
The Solution: AUV Deployment
FMS addressed these challenges by deploying AUVs equipped with high-specification multibeam echosounders and side-scan sonar systems, enabling simultaneous acquisition of high-resolution bathymetric and acoustic imagery data.
Unlike traditional vessel-based line running, the AUVs operated on pre-programmed missions, allowing them to navigate survey corridors autonomously and maintain consistent altitude above the seabed. This ensured uniform data quality and optimal sensor performance throughout the survey.
Deployment from a spot-hire Platform Supply Vessel (PSV) further enhanced operational flexibility while drastically lowering vessel costs.
Operational Efficiency Gains
The adoption of AUV technology delivered substantial improvements in operational efficiency across all phases of the project.
- Autonomous mission planning removed the need for continuous vessel repositioning, reducing downtime and improving overall productivity
- Maintaining a consistent survey altitude enabled optimal sensor performance, resulting in high-density datasets with excellent resolution and coverage. This ensured reliable detection of seabed features and debris, including smaller targets that may be missed by conventional methods
- With efficient acquisition and streamlined processing, the client was able to access processed data earlier, supporting quicker and more informed operational decisions.
Results
- Up to 92% cost reduction.
- Faster project delivery.
- Higher data density and consistency.
- Reduced operational risk.
- Flexible deployment from low-cost vessel.
