Alloys used in Aircraft Fuel Tanks are susceptible to Microbially Influenced Corrosion (MIC).


Microbes have a preference to thrive on surfaces in a film of slimy growth, known as a biofilm.  The activity of microbes within biofilms on metal surfaces can result in Microbiologically Influenced Corrosion (MIC).  MIC of aluminium alloys in aircraft wing tanks is usually due to the accumulation of microbially produced acids, such as iso-citric acid, within biofilms which have developed on the tank surface.  MIC of aluminium alloys in aircraft wing tanks is typified by etching and/or pitting corrosion and may progress at rapid rates.  The microbially generated acids can also increase the water permeability of epoxy based coatings and primers, further exposing the underlying metal to corrosive attack.  Historically, coatings and primers have incorporated chromates to help prevent corrosion and these also have some anti-microbial activity.  However, chromates are not environmentally acceptable and are not used in modern aircraft.

IATA and Aircraft Maintenance Manuals from Airbus, Boeing and other leading aircraft manufacturers recommend routine microbiological testing at a frequency based on the perceived risk of microbial growth.

ECHA can;

  • Conduct analysis of samples of fuel from your aircraft or facility in our laboratory to assess the extent of microbiological contamination and the risk of MIC. Learn more about our lab analysis service here.
  • Provide on-site microbial Test Kits. ECHA’s MicrobMonitor2 is a globally recognised industry standard test (IP 613/ASTM D7978) which can be used on-site or in the laboratory by non-microbiologists for the detection of microbes which can cause acidic corrosion.  Learn more about the test here.
  • Conduct surveys of aircraft wing tanks if you have a concern about MIC. Learn more about our Site Surveys here.
  • Provide advice on remediation, control, monitoring strategies and best practice. Learn more about our Consultancy Services here.
  • Offer comprehensive, tailored training courses on microbiological contamination of jet fuel including management of issues such as MIC. Learn more about our Training Courses here.