Date: 202008
Local time of day: 0601-1200
Location: ZZZ.ARTCC, US
Flight conditions: VMC
Light: Daylight
Aircraft: Small Transport
Operator: Fractional
Flight plan: IFR
Mission: Passenger
Flight phase: Cruise
Airspace: Class A ZZZ
ATC / advisory: Center ZZZ
Reporter organization: Fractional
Reporter function: Captain; Instructor
Reporter qualification: Flight Crew Air Transport Pilot (ATP); Flight Crew Instrument; Flight Crew Multiengine
Human factors: Confusion; Distraction; Situational Awareness
Anomaly: Deviation - Track / Heading All Types; Deviation / Discrepancy - Procedural Clearance; Deviation / Discrepancy - Procedural Published Material / Policy
Detector: Person Flight Crew
When detected: In-flight
Result: Air Traffic Control Issued New Clearance; Flight Crew Requested ATC Assistance / Clarification
Contributing factors: Human Factors
Primary problem: Human Factors

Narrative: This was day 2 with a brand new FO but it was the FO's first day doing a preflight as we started flying the day before after I had an FO swap part the way through the day.  I did the flight planning the night before and had a few conversations with operations about possible passenger catering (that turned out to be an old note) and customs payment arrangements at this airport.  I had read 'ZZZZ' on the trip sheet before getting to the hotel and somehow my brain registered that as 'ZZZZ1' and not 'ZZZZ.'  When I entered my flight plans the night before I instinctively typed in 'ZZZZ1' into [app].  I made sure to get up early to print out all the international paperwork and all other necessary paperwork before we left the hotel so I could devote my full attention and time to the preflight inspection lesson as well as getting the raft in the morning.  After going through the full preflight together; we got the clearance to ZZZZ1 and departed.  Shortly after taking off we were given 'direct destination' by ATC and we did so.  After being given a frequency change ATC again cleared us direct destination.  I stated on the radio that we had already been cleared direct and were proceeding there.  ATC then stated our track was taking us over ZZZZ2 and I zoomed out on the INAV map and saw that ZZZZ had accidentally been entered as the destination instead of ZZZZ1 per the flight plan.  I changed the destination to ZZZZ1 in the FMS and we started flying to the airport.  Just as I did that; however; my FO mentioned that ZZZZ1 was not the airport that was on the trip sheet. I looked; and FO was correct; I had mistakenly filed the flight plan to the wrong airport.  We got an amended clearance from ATC and preceded to ZZZZ.  I called ZZZZ2 radio enroute to get weather and NOTAMs for the new airport and verified our fuel status would still be safe.  We landed at ZZZZ without incident; picked up our passengers and then returned to ZZZ after I refiled the return flight plan.  I can only think that unnoticed built up fatigue from the days before caused the error filing the flight plan.  I started my cycle out west so I transitioned a few time zones and overnighted at ZZZ1 the day before the FO swap causing a long drive to and from the hotel.  Home life has also been stressful; as I have had a few COVID-19 scares with my immediate family.  Since I thought fatigue could be a threat; I decided to stay in ZZZ that night instead of doing the empty repo to ZZZZ2 as originally planned.




Synopsis: Air carrier Captain reported filing the wrong destination and not realizing it until the FO advised they were going to the wrong airport.