Definition
An aircraft oxygen system in which gaseous oxygen is stored in steel cylinders at a pressure of approximately 1,800 to 2,200 psi when fully charged. The high-pressure gas is reduced through a regulator before being delivered to the crew and passenger masks at a usable pressure.
Plain English
An onboard oxygen supply that holds the oxygen as a gas under very high pressure in strong steel bottles. A regulator brings the pressure down to a safe, breathable level before it reaches the masks.
Context Anchor
Seen during oxygen-system descriptions, preflight oxygen checks, oxygen cylinder servicing, and flights where supplemental oxygen may be needed.
Why Pilots Care
Provides reliable oxygen supply to prevent hypoxia when flying above altitudes where normal air is insufficient.
Intuition Check
High-pressure does not mean the pilot breathes oxygen at high pressure. It means the oxygen is stored under high pressure, then reduced before use.
Example Sentence 1
During preflight, the pilot checked the high-pressure oxygen system and confirmed the cylinder gauge read 1,850 psi.
Example Sentence 2
When the cabin lost pressure, the high-pressure oxygen system supplied breathable gas to the crew masks.