Definition
The branch of physics and engineering concerned with the mechanical properties and behavior of compressed air or other gases, and the use of that pressurized gas to do work or transmit force in aircraft systems.
Plain English
Pneumatics is the use of pressurized air to power things on the aircraft — like operating brakes, opening valves, inflating door seals, or driving instruments.
Context Anchor
Seen in aircraft maintenance discussions of air-operated systems, shop equipment, and components that use pressurized air instead of liquid or electricity.
Derivation
From the Greek pneuma, meaning 'breath' or 'air.' The same root appears in 'pneumonia' (a lung condition). In aircraft, it points to anything that runs on moving or pressurized air.
Why Pilots Care
Pneumatic systems provide backup or primary power for critical functions like braking and de-icing, so pilots must understand their operation for normal and emergency procedures.
Analogy
A bicycle pump is a simple pneumatic idea: you squeeze air into a smaller space, and that pressurized air can do useful work.
Intuition Check
Do not confuse pneumatics with hydraulics. Pneumatics uses pressurized air or gas; hydraulics uses pressurized liquid.
Example Sentence 1
On many large aircraft, the pneumatics system supplies high-pressure air bled from the engines to operate the air conditioning and anti-ice systems.
Example Sentence 2
During the preflight, the mechanic bled the pneumatic lines to remove any trapped moisture.