Definition
An automated computer program used by air traffic control to assign departure times to aircraft, spacing them so they fit smoothly into the en route traffic flow.
Plain English
A computer tool ATC uses to decide what time each aircraft should take off, so departing traffic blends safely and efficiently with aircraft already in the air.
Context Anchor
A pilot may encounter this before taxi or takeoff when ATC is managing how departures enter busy airspace.
Derivation
“Departure” means leaving, and “sequence” means putting things in order. Here, the important idea is not just that aircraft are leaving, but that their departures are arranged in a planned order to create proper spacing.
Why Pilots Care
It prevents long lines of aircraft waiting on the taxiway and reduces unnecessary fuel burn from holding.
Analogy
It is like letting cars enter a busy highway one at a time so they do not all reach the same merge area at once.
Intuition Check
Do not assume this only means the order airplanes take off from the runway. In this FAA context, it means ATC is spacing departures so they reach a common point in the airspace at the proper interval.
Example Sentence 1
Tower advised us our wheels-up time was assigned by the departure sequencing program, so we needed to be at the runway and ready to roll on time.
Example Sentence 2
Because of the Departure Sequencing Program we taxied to the hold-short line and waited for our slot rather than departing immediately after the previous aircraft.