Historic flight date from 2001 [duplicate]

This might be better-suited to Aviation.SE or even History.SE as it does not seem to pertain to the needs of a current traveler, but I will say it will take non-trivial effort to confirm flight information from as long ago as 2001.

OAG, the database company that powers almost all airline schedule and flight status information in the world, only has historical flight data going back to 2004. Even aggregated FAA statistics on flight delays and cancellations are only available from 2003, much less for an individual flight.

Historical flight schedules will probably be easiest to locate, even without an OAG subscription. In that era, airlines still published paper timetables, and there are many people around the world who collect them now as memorabilia, and who post scans or photographs of them online. If a PDF timetable was available, someone probably has a copy of it as well. The timetable will usually provide flight numbers, scheduled departure and arrival times, stopover points, equipment types, and meals served.

You might similarly be able to identify the aircraft used because planespotters may have recorded the tail number, although this is obviously very hit-and-miss, especially for smaller airports and smaller airlines.

You can probably make an educated guess as to which terminal the flight operated from based on historical information about the flight and about the airport itself.

But as to whether a specific flight operated and whether or not it was on time, and whether it operated with its normally scheduled crew and aircraft from its normally scheduled terminals, is another matter. You may have few options except to contact the airline itself and ask if it can look up this information for you, or perhaps hope to get in touch with a crew member, airport worker, or other passenger who might have recorded such information in a personal journal and thus be somewhat more reliable than one person's memory.