FUEL REACTION

[Natstrackalpha]

Hi, we have facilites for storing samples of fuel for a period as per CAA/ICAO regulations.recommendations/SOPs/etc.

Another company stored Avgas samples which got hit by the sunlight and have developed a milky opaque colour, instead of the usual crystal clear blue. So - to experiment he put a sample of their fuel into our cupboard and let one of his samples stay in the sporadic sunlight.

We shall see, in a weeks time what the result could be.

Anyone have any knowledge of discolouration of AvGas?

Personally, I think their fuel must have had porridge in it, judging by the colour!

[UAVop]

Depending on the location and conditions, the fuel can photoxidize with exposure to sunlight, and combine with other chemicals in the surrounding air.

It seems much more likely that the exposure to sunlight caused a bacteria or fungi bloom. These are the same bugs that they use to bio-remediate fuel in the soil.

Looks like you should have them check the water content.

Microbial contamination endangers both fuel quality and fuel systems. Some of the common manifestations and consequences of the problem are outlined below.

Fuel Quality:
Aviation fuel should be "clear and bright". Contaminated fuel is often hazy. The primary cause is an increase in the water content of the fuel resulting from the production of biosurfactants. These are by-products of microbial growth and alter the surface tension at the fuel/water interface. In consequence. the solubility of water in the fuel is increased.

Additive Degradation:
Many additives present in fuels can be readily degraded by micro-organisms. This means their effect is lost and in consequence the fuel may no longer meet specification.

Structural Damage:
Certain micro-organisms can digest components of surface coatings or fuel lines, thus greatly reducing their in service life. Others, known as sulphate reducing bacteria (SRB), cause microbially induced pitting corrosion.

Filter Plugging:
Biopolymers are formed during microbial growth. These are gummy products which block fuel lines and plug filters