Definition
A specific time, assigned by Air Traffic Control under a traffic management program, at which an aircraft is expected to depart. The aircraft must take off within a defined window around this time (typically plus or minus five minutes) so it fits into the metered flow of traffic into a destination airport or congested airspace.
Plain English
A take-off time given to you by ATC because the system is busy. You have to leave the ground close to that time — not earlier, not much later — so you slot into the line of arrivals at your destination.
Context Anchor
You may see an EDCT in an IFR clearance, a release from clearance delivery or ground control, or a delay notice before departure.
Derivation
Built from plain English: 'Expect' (anticipate), 'Departure Clearance' (permission to leave), and 'Time' (the specific moment). The word 'expect' is doing real work here — it signals that this time is planned and reserved for you, not just a suggestion. Missing it usually means losing your slot.
Why Pilots Care
Knowing your EDCT allows pilots to manage fuel, passenger expectations, and departure timing to avoid unnecessary holding or delays.
Analogy
Think of it like an assigned appointment time for takeoff. You are not simply leaving whenever ready; ATC is fitting your departure into a larger traffic plan.
Intuition Check
Do not read “expect” as a casual guess here. An EDCT is an assigned ATC time, not a suggestion and not the same as already being cleared for takeoff.
Example Sentence 1
Ground gave us an EDCT of 1845Z, so we planned engine start to make sure we'd be airborne within the five-minute window.
Example Sentence 2
We adjusted our departure time to meet the assigned EDCT and avoid additional delays.