July 16, 2026
Ted Lemieux, Head of the Center for Corrosion Science and Engineering Branch at the Naval Research Laboratory (NRL), explains how the Insertable Stalk Inspection System 360 is helping the Navy inspect ballast tanks more safely while giving maintenance planners better information to keep ships mission ready.
Ships contain a variety of tanks that hold seawater, fuel, and drinking water, each creating different corrosion challenges. Regular inspections are essential because much of a ship's structural integrity depends on these enclosed spaces remaining in good condition. Traditionally, those inspections require trained personnel to physically enter the tanks, a process that is both labor intensive and potentially dangerous due to confined spaces and hazardous gases.
Beyond the safety concerns, Lemieux says inspectors must make highly precise judgments about the condition of protective coatings. Those assessments directly influence maintenance decisions across a fleet that includes roughly 15,000 tanks, making accuracy critical.
To solve that problem, NRL began exploring alternatives more than two decades ago as part of an Office of Naval Research Future Naval Capabilities program focused on condition-based maintenance. Researchers evaluated a wide range of technologies, including sensors capable of measuring corrosion without opening a tank and remotely operated inspection systems designed to eliminate the need for human entry.
Over time, those concepts evolved into a deployable inspection capability. Although the technology was delivered around 2010, changes in the Navy's maintenance planning process delayed widespread adoption. That changed when Commander, Navy Regional Maintenance Centers approached NRL to inspect tanks aboard a forward-deployed ship in Japan.
That opportunity coincided with significant advances in commercial camera technology.
Rather than relying on older pan-tilt-zoom cameras that required operators to slowly capture hundreds of individual images throughout a tank, NRL adopted a dual-lens 360-degree camera system capable of capturing an entire spherical view in a single pass. Lemieux says the shift dramatically reduces inspection time while simplifying the overall process.
The hardware refresh also includes improved battery-powered lighting and updated software, making the system more practical for fleet-wide deployment. Following the successful inspections in Japan, Navy maintenance leaders began working with NRL to expand use of the technology across the fleet.
While the hardware represents a major improvement, Lemieux says the software continues to evolve as well.
Earlier versions relied on internally developed software that used color and edge detection techniques to identify coating damage. Today, NRL is beginning to incorporate newer machine learning capabilities that can distinguish structural components from other objects inside tanks and evaluate additional features during inspections.
Those advances create opportunities to gather more actionable information from every inspection while reducing the amount of manual analysis required.
Lemieux also highlights the value of collaboration with industry throughout the project's development. Some partnerships stem from long-standing research relationships, while others leverage innovations already occurring in commercial sectors such as digital construction intelligence. Those technologies use optical information to automatically assess construction quality, identify deviations, and annotate digital images. NRL sees opportunities to adapt similar capabilities for ship maintenance, exterior inspections, paint quality assurance, and other applications.
Ultimately, Lemieux says the greatest benefit of the system extends beyond faster inspections.
By giving maintenance planners a clearer picture of tank conditions before a ship enters dry dock, the Navy can better determine exactly which tanks require preservation work. That reduces unnecessary maintenance, minimizes unexpected discoveries during ship availabilities, and gives planners greater confidence when building maintenance schedules.
For Navy leaders focused on improving fleet readiness, better planning translates directly into more efficient maintenance periods and fewer delays. According to Lemieux, helping maintenance organizations achieve world-class planning for tank maintenance remains the central goal of the effort, ensuring ships spend less time waiting for repairs and more time ready to execute their missions.