Re: Synthetic vs Organic for airplane engines

[Paul Nicholson <paul@eisusa.com>]

Just thought I'd mention that synthetic oil has fallen out of favor (favour
for the queen's subjects) for aircraft use on small internal combustion
engine airplanes. The reason is that it does not have the sustained coating
capability of mineral oils.

Light aircraft are typically idle for weeks at a time, and synthetic oils
drain off the inside of the cylinders, exposing the bare metal to air
contact. This promotes rust of the cylinder walls, leading to compression
loss and an early teardown on the engine. Mineral oils coat the cylinder
wall better and result in less corrosion.

If the airplane is used consistently this is not a factor as it is for our
quattro's which typically get driven almost every day.

Paul