B767 flight crew reported landing at an airport not authorized per company ops specs.

Attributes
ACN	1605118
Time
Date	201812
Local Time Of Day	0001-0600
Place
Locale Reference	ZZZ.Airport
State Reference	US
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Make Model Name	B767-300 and 300 ER
Operating Under FAR Part	Part 121
Flight Plan	IFR
Person 1
Function	Captain Pilot Flying
Qualification	Flight Crew Multiengine Flight Crew Instrument Flight Crew Air Transport Pilot (ATP)
Experience	Flight Crew Last 90 Days 60 Flight Crew Total 14000 Flight Crew Type 3000
Person 2
Function	Pilot Flying Captain
Qualification	Flight Crew Multiengine Flight Crew Air Transport Pilot (ATP) Flight Crew Instrument
Events
Anomaly	Deviation - Procedural Published Material / Policy Deviation - Procedural FAR

Narrative:

I am submitting this report as a result of being informed by [company] representative that a flight; or flights; I operated were potentially in violation of crash fire rescue equipment 121.555. I was unaware of this at the time I was scheduled and then operated the potentially violation flights. Although I understand it is the joint responsibility of the crew (captain) and the dispatcher to ensure the airport is opspecs legal before the operation of a flight; it is not the norm to check each and every leg in a regularly scheduled; [dispatch packet] produced and approved flight segment and pairing. First officer and I operated without being aware that ZZZ was listed as an alternate; not a destination airport in opspecs for [company] boeing 767 aircraft. We were made aware of this via email. Captain and first officer operated the following flights with aircraft X; a B-767-300. [We flew a] city pairings we do not normally operate; but to our knowledge were normal domestic gateways. This was a trip in the published [dispatch package] and had no reason to believe any discrepancies or legal issues were involved in operating this trip. Perhaps in the future we as a crew and certainly me as the captain will query the dispatcher more often when operating unfamiliar city pairs for legal issues in addition to my normal communication with dispatch.

Original NASA ASRS Text

Title: B767 flight crew reported landing at an airport not authorized per company Ops Specs.

Narrative: I am submitting this report as a result of being informed by [Company] representative that a flight; or flights; I operated were potentially in violation of CFR 121.555. I was unaware of this at the time I was scheduled and then operated the potentially violation flights. Although I understand it is the joint responsibility of the crew (Captain) and the Dispatcher to ensure the airport is OPSPECS legal before the operation of a flight; it is not the norm to check each and every leg in a regularly scheduled; [dispatch packet] produced and approved flight segment and pairing. First Officer and I operated without being aware that ZZZ was listed as an Alternate; not a Destination airport in OPSPECS for [Company] Boeing 767 aircraft. We were made aware of this via email. Captain and First Officer operated the following flights with Aircraft X; a B-767-300. [We flew a] city pairings we do not normally operate; but to our knowledge were normal domestic gateways. This was a trip in the published [dispatch package] and had no reason to believe any discrepancies or legal issues were involved in operating this trip. Perhaps in the future we as a crew and certainly me as the Captain will query the dispatcher more often when operating unfamiliar city pairs for legal issues in addition to my normal communication with Dispatch.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.