Communications facilities—supplemental operations

This regulation sets communication requirements for Part 121 supplemental carriers operating passenger flights (not all-cargo) in aircraft with more than two engines.

Basic requirement: Operators must have reliable two-way radio communication between the aircraft, the company, and air traffic control throughout the entire route.

ETOPS operations add stricter requirements:

• For standard ETOPS: Voice communication must be available where facilities exist, considering potential diversion routes and altitudes to ETOPS alternates. If voice isn't possible, another communication system must substitute.

• For ETOPS beyond 180 minutes: A second communication system is required, capable of immediate satellite-based voice communications with landline telephone quality, connecting flight crews to both ATC and the company. Again, if satellite voice isn't available or adequate, another system must substitute.

These requirements ensure flight crews can communicate during extended overwater operations when immediate coordination may be critical for diversions or emergencies.

*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.*