Rules applicable to operations in a foreign country

When operating in a foreign country, Part 121 certificate holders (airlines) must follow that country's air traffic rules and local airport procedures. However, there's an important exception: if a specific Part 121 rule is *more restrictive* than the foreign country's rule, the airline may follow the stricter Part 121 requirement instead—provided doing so doesn't violate the foreign country's regulations.

In practice, this means airlines generally defer to local rules when operating internationally, but they can maintain their own higher safety standards when those standards exceed local requirements. For example, if Part 121 requires more restrictive weather minimums than a foreign country allows, the airline can use the stricter minimums as long as this doesn't conflict with that country's mandatory procedures. The regulation balances respect for foreign sovereignty with maintaining consistent safety standards across an airline's operations.

*This is a plain-English summary for study only. The official 14 CFR text on this page is controlling — always read the current regulation and consult a CFI.*