Probabilistic Data Collection
GCAS created the CORRDBMS system used by TACOM for tracking the corrosion of the fielded fleet. CORRDBMS is unique in its ability to extract corrosion rate information from uncontrolled field observations. Corrosion field observations suffer from a number of disadvantages compared to controlled laboratory corrosion tests. Field measurements consist of performing a number of visual inspections of vehicles over non-uniform time intervals. Frequently, long periods elapse between observations and the conditions and atmospheric environment vary in both its severity and duration. Vehicle command operation and maintenance data needed to construct the vehicle’s “use” history between observations is often incomplete and erroneous. CORRDBMS uses a statistical Finite State Machine (FSM) model to represent transitions between the different corrosion states of the vehicle. Dependencies between similar components and parts on the vehicle, operational use, road conditions, and environment (corrosion index) are determined using a multi-variant/multi-regression analysis of the composite assembled data. Maintenance and repair data, traced to the observed vehicles, are used to calculate Fleet Readiness, Life Cycle Cost and Time to Repair/Replace under different degrees of corrosion deterioration.
GCAS also developed the AIRS (Aircraft Inspection and Repair System) for aircraft corrosion data collection under US Air Force contract to automate corrosion maintenance and repair data collection on the aging C141 aircraft. AIRS is unique in its ability to describe the geometry of the aircraft’s surface and structure in a detailed accurate three dimensional model which is used to precisely pinpoint the location of the corrosion.