Many different types of microorganisms are able to proliferate in jet fuel. In excess amount, microbial contamination can cause many problems for aircraft. The most abundant metabolites produced by microbial communities are low molecular weight organic acids. These can create pitting corrosion in wing tanks, and structural instability. In small jets, it may even result in the need for wings to be removed so that the corrosion can be cut out and the structure restored to a serviceable condition. As microorganisms grow, they form biomass (accumulation of microbial cells) and biofilms (complex formations of cells and extracellular substances), which can adversely affect several aircraft fuel wetted components such as fuel probes affecting their ability to accurately report the aircraft fuel load. Fuel Quantity Indication System failure can be catastrophic.
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