Definition
A soft, porous leather cloth used as a filter during aircraft refueling to trap solid contaminants and separate water from aviation fuel. Fuel passes through the chamois while water beads up and is held back, helping ensure clean, water-free fuel enters the tank.
Plain English
A piece of soft leather used like a filter when fueling an aircraft. Fuel goes through it, but dirt and water do not.
Context Anchor
Seen in refueling procedures, especially when fuel is poured from a container through a funnel into an aircraft fuel tank.
Derivation
Chamois (pronounced 'shammy') comes from the French name for a small mountain goat or antelope, whose hide was traditionally used to make this kind of soft, absorbent leather. The same material is familiar from car detailing, where it's used to dry paintwork without scratching.
Why Pilots Care
Water in fuel can cause engine failure; the chamois provides a simple field check before flight.
Grounding Statement
Picture fuel being poured through a funnel lined with soft leather: the fuel goes into the tank, while water and dirt are more likely to stay behind.
Intuition Check
Do not think of chamois skin as just a cleaning cloth. In this refueling context, it is being used as a fuel filter to help keep water and dirt out of the tank.
Example Sentence 1
When refueling from a drum in the field, the line crew poured the avgas through a chamois skin to catch any water or debris.
Example Sentence 2
Keep a dry chamois skin available when refueling from drums at remote strips.