Below is the context.
Do we need to create a table to catch any in-flight data during the cut-over?
I looked the word in-flight
up in several dictionaries and almost all of them state the meaning of it is:
Occurring, carried out, or present while in flight
But from the aforementioned context I think the meaning here probably is `something happened during a process". Apparently this has nothing to do with a flight. Hope some native speakers can help to confirm.