Definition
A vertical pipe inside a fluid tank that extends upward from the bottom, with its open end positioned above the tank floor so that fluid is drawn from a level higher than the lowest point of the tank. This reserves the fluid below the standpipe's intake for a separate system or emergency use.
Plain English
A pipe that sticks up inside a tank so it draws fluid from partway up rather than from the very bottom. The fluid sitting below the pipe's opening stays in the tank, held back for another purpose.
Context Anchor
Seen in aircraft fuel tanks, fluid reservoirs, and maintenance descriptions of tank outlets, drains, or reserve levels.
Derivation
From 'stand' (to stand upright) plus 'pipe.' It literally describes a pipe that stands up inside the tank rather than lying flat or drawing from the bottom.
Why Pilots Care
Reduces the chance of drawing water or sediment into the fuel lines, protecting engine operation and flight safety.
Analogy
Think of a drinking straw cut short and propped up in a glass. It can only sip from above a certain level. Whatever is below the straw's opening stays in the glass.
Intuition Check
Do not read standpipe as just any pipe that stands upright. In this aircraft use, the important point is that the pipe sets the height where liquid can flow.
Example Sentence 1
The hydraulic reservoir uses a standpipe so that a leak in the main system cannot drain the fluid reserved for the emergency brake system.
Example Sentence 2
During the inspection, water was found below the standpipe inlet, confirming the design had protected the fuel system.