Definition
Air-filled rubber tires fitted to an aircraft's landing gear. They are inflated to a specified pressure so that the compressed air inside, together with the flexible tire structure, absorbs and cushions impact loads during taxi, takeoff, and landing.
Plain English
The wheels of the airplane have rubber tires filled with pressurized air. The air inside acts like a cushion that softens the bumps and shocks when the airplane rolls along the ground or touches down.
Context Anchor
Seen when discussing landing gear, preflight tire checks, and inspections after a hard landing.
Derivation
From the Greek 'pneuma,' meaning 'breath' or 'air.' A pneumatic device is one that works using air pressure. Knowing this makes it clear that a pneumatic tire is simply a tire that does its job by holding pressurized air.
Why Pilots Care
The air in the tires is part of how the airplane absorbs landing loads. Underinflated, overinflated, or worn tires reduce that cushioning effect and can contribute to a harder-feeling landing or damage during a firm touchdown.
Analogy
A pneumatic aircraft tire is like a very strong bicycle or car tire: its shape and cushioning come from pressure inside it. The aircraft version is built to handle much heavier loads and harder impacts.
Intuition Check
Do not read pneumatic as meaning powered by air like an air tool. For tires, pneumatic simply means inflated with pressurized gas.
Example Sentence 1
During preflight, the pilot checked that the pneumatic tires were properly inflated and free of cuts or flat spots.
Example Sentence 2
A hard landing can damage pneumatic tires even when the rest of the landing gear appears undamaged.