The development was sparked by the discovery that the rate of biofilm formation in the aircraft fuel tanks had been steadily on the rise for several years. Biofilm is the result of secretions from microbes, which can multiply very quickly under unique circumstances.
The microorganisms find their way into aircraft tanks both through the air vents on the wings and via the clothes and respiration of mechanics during fuel tank cleaning. The condensation that forms in the tank provides an almost perfect biotope for microbes to grow and multiply rapidly.
"The biofilm produced by microbes is more than just a form of visual pollution; it can cause significant damage to aircraft. For example, the microbes can penetrate the smallest cracks, attack the aluminum alloy and lead to corrosion on the wing," says Ralf Riemann, Coordinator in Lufthansa Technik's VIP & Special Mission Aircraft Services division.
"Heavy infestations can have an extremely negative effect on the reliability of flight operations and lead to unplanned ground time and high costs for rectifying the problem. And when larger areas are affected by corrosion, the aircraft even have to go in for repair lasting several weeks," explains Dr. Christian Siry, Head of Central Materials Technology at Lufthansa Technik.
Increasing resistance to biocides and gradual changes in the microbe population suggest that traditional methods for identifying and eliminating microbes are no longer sufficient. This makes it all the more important to inspect the tanks regularly, using new measuring technology and reliable analytical methods, since this is the only way to prevent a critical infestation.
So it pays off for all aircraft operators to look at their tanks both more frequently and more closely. Dr. Christian Siry and Ralf Riemann are available to contribute their expertise and look forward to an opportunity to share experiences.