Cargo Jet Fuel Filter Contamination Evaluation
A fuel filter from a Cargo Jet was found to be partially plugged with a carbonaceous sludge. In addition to a major concentration of carbon, oxygen and sulfur also were identified in the filter. Relatively low concentration of other elements including Mg, Na, Ca, Cl, Si, K, Fe, Cr, Ti and Zn.
FTIR analysis identified aliphatic hydrocarbons as well as a sulfur-oxygen functional group. GC-MS analysis identified many compounds associated with the fuel (i.e. Jet Fuel A). However, a fatty ester ester (i.e. adipic acid) was identified in the contamination by GC/MS evaluation. Adipic acid is used in the preparation of esters for use as lubricants and plasticizes suggesting contamination of the Jet Fuel.
Metallic particles comprised primarily of aluminum form a minor constituent of the contamination. These metal particles were likely derived from wear of a 2000 Series Aluminum Alloy such as AA 2025.
Photograph showing sludge-like contamination on cut opened filter.
Sludge and particles extracted from the fuel filter.
Photograph of the fuel filter as-received.
Stereomicroscope photograph showing the dried sludge.
Fourier Transformed Infrared (FTIR) Spectrum Spectrum generated from the bulk sludge
EDS elemental spectrum of the bulk sludge sample.
Gas Chromatography/Mass Spectroscopy (GC/MS)chromatogram generated from the sludge sample.
Scanning electron micrograph showing two cutting-type wear metal particles extracted from the sludge.
