Advanced Metalworking Solutions for
Naval Systems that Go in Harm's Way

GTC Durability Coating

Applying a durability coating to GTC SONAR baffle tiles will increase the service life of the tiles and reduce total ownership costs. NMC photo


A Navy Metalworking Center (NMC) project team is working to improve the GTC SONAR baffle tiles installed on SEAWOLF and VIRGINIA Class submarines (VCS).


During a recent Extended Drydocking Selected Restricted Availabilities (EDSRAs), several GTC tiles on SEAWOLF and VIRGINIA Class submarines (VCS) required replacement due to cracks and delamination.

Technical Approach

Applying a durability coating to the tile edges will eliminate these issues and ensure that the tile lasts throughout the life of the ship. The NMC project team is extensively testing materials and process parameters to ensure a sufficient durability coating is implemented and to verify compatibility with the tile material and longevity in this environment.


The potential net cost savings for in-service VCS over the next five years is $3M for five hulls. The project will also reduce total ownership cost of future VCS by $6M over the next five years, assuming 10 hulls will be built. Project results could also mitigate and avoid $4.4M in repairs on SEAWOLF Class submarines SSN 22 and SSN 23. Total cost benefits for in-service VCS and SEAWOLF and new construction VCS total $13.4M.


Once the VCS and SEAWOLF program offices accept the project recommendations, implementation will occur in two ways. First, the coating will be applied on in-service hulls during EDSRA at the appropriate Naval Shipyard & Intermediate Maintenance Facility after inspection of the tile. It is expected that a contractor will apply the durability coating on the GTC tile using materials and process parameters developed during this project. The first application is expected to occur on SSN 777 in mid-2015. The second implementation will also occur in mid-2015 for new construction of VCS. The durability coating is expected to be applied at the GTC tile manufacturer, Globe Composite Solutions, after General Dynamics Electric Boat completes a procurement specification change. The construction shipyard will receive the tile with the coating in place; therefore, construction activities should not be impacted. The implementing organizations will revise drawings and procedures that define the addition of the durability coating.




Charles McNamara
Asst. Program Manager for Virginia Class Development and Modernization
Naval Sea Systems Command, PMS 450D


Naval Surface Warfare Center, Carderock Division
PMS 450 Virginia Class Program Office
Pearl Harbor Naval Shipyard
PMS 392 - Strategic/Attack Submarines
Globe Composite Solutions