What Is OOOI? Definition & Meaning in Aviation
OOOI stands for Out, Off, On, In: the four events that mark a flight, being pushback from the gate, takeoff, landing and arrival at the gate.
In plain language
Airlines record these times automatically. Together they give the taxi-out time, the airborne time and the taxi-in time.
Example
A Karachi to Islamabad flight might be Out at 08:00, Off at 08:18, On at 09:40 and In at 09:48.
Why it matters
OOOI times let airlines measure every phase of a flight and build realistic schedules. They are also behind the status words you see, such as “departed” (often Out) and “landed” (On).