Definition
An early, provisional estimate of when an arriving aircraft is expected to touch down at the destination airport, calculated by air traffic management tools as part of arrival sequencing and flow control. The TCLT is refined as the flight progresses and is later replaced by a firmer calculated landing time once sequencing decisions are locked in.
Plain English
It is a first-guess landing time for an arriving aircraft that controllers use to plan the arrival flow. The word 'tentative' means it can still change as the flight gets closer.
Context Anchor
Seen in FAA acronym lists, traffic management discussions, dispatch planning, and other timing information related to arrivals.
Derivation
Tentative' comes from the Latin 'tentare', meaning to try or test — so a tentative time is a trial estimate, not a final commitment. That fits exactly: the TCLT is a working estimate that gets adjusted as better information arrives.
Why Pilots Care
It helps pilots manage descent timing, fuel, and speed adjustments during arrival.
Intuition Check
Do not read TCLT as a fixed appointment to land. It is a calculated planning time that can change before the aircraft actually lands.
Example Sentence 1
The arrival metering display showed a TCLT of 1842Z, giving the crew an early sense of when they would be on the ground.
Example Sentence 2
Our TCLT was updated by five minutes due to a preceding arrival.