Electrical and Physical Nature of Microbial Membranes Implicated in Aircraft Fuel Quantity Probe Malfunction 710439

Microorganisms contaminating aircraft turbine fuels are known to cause severe corrosion in jet aircraft integral fuel tanks. Microbial deposits on fuel quantity capacitance probes are also suspected of causing malfunction of these probes. To determine how microbial contamination can cause quantity probe malfunction, an artificial environment conducive to the rapid growth of microbial membranes was developed. Studies were conducted on membranes grown in this environment to determine their electrical conductive properties showing that the membranes in their natural state exhibited a low resistance, thus indicating that they were sufficiently conductive to cause fuel quantity probe malfunction.These results were confirmed by placing laboratory-grown membranes at different locations on a fuel quantity probe and measuring changes in capacitance and resistance of the probe.