Susan S. Mueller1, Loryn L. Bowen1, Marlin D. Vangsness1, Lori M. Balster1, Lisa M. Brown1, Ellen M. Strobel2, and Lt. Daniel D. Pike2. (1) Energy and Environmental Engineering, University of Dayton Research Institute, 300 College Park, Dayton, OH 45469, (2) Air Force Research Laboratory, United States Air Force, 1790 Loop Road North, Wright-Patterson AFB, OH 45433
Since the 1950’s, aviation fuel in the United States Air Force fleet has been investigated for possible microbial contamination. Bacterial issues with fuel were documented when a B-52 crashed in 1958 and the cause was related to bacterial plugging of an in-line fuel filter. Improvements in fuel tank housekeeping and the addition of a fuel system icing inhibitor lowered the microbial population. Research was then stopped and wasn’t looked at again until recently when contamination rates began to rise.
The University of Dayton Research Institute in conjunction with the United States Air Force Research Laboratory is studying microbial contamination of jet fuel from various Air Force bases and air frames. Even though there are documented methodologies for testing hydrocarbons for bacteria, methods used within this lab are continuously under review for better microbial recovery. Currently, traditional plating and polymerase chain reaction (PCR) are used to test samples in addition to archiving the DNA from the samples using FTA paper.
Over approximately two years, fuel samples were collected from fifteen United States Air Force bases. Additionally, small-quantity samples of alternative fuels, such as biodiesel, biojet and Fischer-Tropsch, were also collected. Each fuel tested was archived on to FTA paper, cultured, and tested using PCR. Most samples that showed contamination were then sequenced for identification. Techniques in culturing and PCR preparation were looked at with each group of samples tested and the methods used along with the results recovered were examined to determine what worked and didn’t work within the current protocol.
