Definition
A device that produces a controlled time delay between an input signal and the resulting output action, counting down from a preset interval before triggering the next event in a sequence.
Plain English
A timer that waits a set number of seconds after being triggered, then makes something happen. It counts down quietly in the background until its time is up.
Context Anchor
Seen in aircraft systems, avionics, and maintenance descriptions where one action must wait a controlled amount of time before the next step occurs.
Why Pilots Care
Many automatic systems rely on short, deliberate delays to avoid false triggers or to allow one action to settle before another begins. Knowing a delay timer is in the loop helps explain why a system reacts a moment after a switch is flipped rather than instantly.
Analogy
It is like setting a kitchen timer before taking food out of the oven. Nothing is wrong during the wait; the timer is simply counting down to the next action.
Intuition Check
Do not read “delay” here as an accidental lateness or problem. Here, it means an intentional waiting period built into the system.
Example Sentence 1
The fire-extinguishing system uses a delay countdown timer so the bottle discharges a few seconds after the warning is confirmed.
Example Sentence 2
After pressing the button, the delay countdown timer paused briefly then began its audible alert sequence.