Definition
Materials capable of catching fire and burning when exposed to sufficient heat in the presence of oxygen. In aviation maintenance and operations, the term covers fuels, oils, solvents, certain fabrics, papers, and other substances that will sustain combustion once ignited.
Plain English
Things that can catch fire and keep burning. In and around aircraft, this includes fuel, oil, cleaning fluids, rags, and similar items.
Context Anchor
Seen in aircraft maintenance, hangar safety, fueling areas, fire-prevention procedures, and emergency equipment discussions.
Derivation
From the Latin 'comburere', meaning 'to burn up'. The '-ible' ending means 'able to be'. So 'combustibles' literally means 'things able to be burned'.
Why Pilots Care
Uncontrolled combustibles create immediate fire risks that can damage aircraft or endanger people on the ground.
Intuition Check
Do not assume combustibles means only gasoline or obvious fuel. It can also mean ordinary burnable items, such as oily rags, paper, or cleaning supplies, if they can feed a fire.
Example Sentence 1
The mechanic stored all combustibles in the approved metal cabinet at the rear of the hangar.
Example Sentence 2
Hangar rules required combustibles to be stored in approved metal cabinets at least twenty feet from any parked airplane.