Product Highlights

Reliability of Underwater Connectors (MIL-C-24231 and MIL-C-24217)

The Portsmouth connector is the most commonly used underwater connector on ballistic missile submarines (SSBNs). Due to electrical connector failures, submarines have required dry-docking as often as every two years. TRI performed shipboard inspections and laboratory connector failure analyses to identify possible failure mechanisms, and used accelerated life testing (ALT) and development of design modifications. Cathodic delamination of the rubber to metal bond in the connector can occur when the electrical field used in cathodic hull protection systems induce hydroxide ion formation at the bond interface. TRI developed and commercialized a solution to this problem that involves a nonconductive coating (NCC) formed from a plasma spray ceramic and polymer sealer. TRI’s Bond-Coat is now a fleet required standard for submarine MIL-C-24231 and MIL-C-24217 connectors. It is also used in down-hole connectors, offshore applications, and in other harsh environments that challenge rubber to metal bonds.

Composite SHM for Aircraft

Under funding from the Navy and Army SBIR programs, TRI is developing small lightweight systems to monitor the health of composites. It continuously monitors, collects and processes data in near real time using acoustic emission. The composite health diagnosis is completed within a few seconds and stored for download at the next inspection period. This lightweight, miniaturized, distributed monitoring system also has the potential to be adapted to metallic health monitoring.

Detecting Corrosion under Paint

Currently, aircraft must often be depainted to enable inspection for hidden corrosion. If hidden corrosion is found, it may have progressed to the state where the aircraft skin must be ground down until it is gone, sometimes rendering the skin unusable. Under funding from the Air Force SBIR program, TRI is developing a system which can locate corrosion hidden under paint without depainting and determine pit size and depth. This enables the maintenance crew to determine up front if there is corrosion and if so, whether the skin should be ground for repair or replaced.