Definition
A device installed in an aircraft system to remove moisture from air, gas, or fluids. In pneumatic and oxygen systems, dehydrators use a desiccant material that absorbs water vapor as the gas passes through, protecting downstream components from corrosion, freezing, and contamination.
Plain English
A small unit that pulls moisture out of the air or gas flowing through a system, so water doesn't build up where it could cause damage.
Context Anchor
Seen in aircraft maintenance discussions, especially around air-conditioning, pneumatic, and other systems that must stay dry inside.
Derivation
From the Latin 'de-' (away, removal) and 'hydro' (water). A dehydrator literally means 'water remover' — which matches exactly what it does in the system.
Why Pilots Care
Moisture left in lines can freeze at altitude, cause corrosion, or lead to system failure in brakes, instruments, or de-icing equipment.
Intuition Check
A dehydrator here is not about a person being dehydrated. It is a device that removes water from an aircraft system.
Example Sentence 1
The mechanic replaced the dehydrator cartridge during the annual inspection because its color indicator showed it had absorbed its limit of moisture.
Example Sentence 2
With the dehydrator functioning correctly, the oxygen system delivered dry gas that would not form ice at altitude.