Lower the risk of costly corrosion
This is a Main Landing Gear Strut Cylinder Head off of a PA-28-181 strut, (our STC prototype Aircraft), after we removed the strut.
Limited visibility of the Strut Cylinder Head and Strut placement makes it very difficult to inspect for corrosion during scheduled Inspections.
It's clear that moisture has found its way in and did enough damage that it had to be replaced. The Cylinder Head is steel and recessed in the top of the Strut which makes it easy for moisture to collect and very difficult for moisture to dissipate.
Once your Access Panel Kit is installed, the Inspecting Technician will have enough room to inspect the Strut Cylinder Head for damaging signs of corrosion and treat the area before problems occur.
Corrosion Defined as
The deterioration of materials by chemical interaction with their environment. The term corrosion is sometimes also applied to the degradation of plastics, concrete and wood, but generally refers to metals.
FAA Advisory Circular 43-4B discusses the data regarding identification and treatment of corrosive attack on aircraft structures:
"Corrosion is a natural phenomenon which attacks metal by chemical or electrochemical action and converts it into a metallic compound, such as an oxide, hydroxide, or sulfate. The corrosion occurs because metals tend to return to their natural state". Four conditions must exist before corrosion can occur:
- Presence of an anode, or a metal that will corrode;
- Presence of a cathode, a dissimilar conductive material which has less tendency to corrode;
- Presence of an electrolyte, a conductive liquid; (such as water in this case)
- Electrical contact between the anode and cathode, which is usually by metal-to-metal contact, or through a fastener.
Elimination of any one of these conditions will stop corrosion.