Helicopter terrain awareness and warning system (HTAWS)

This regulation requires all helicopters used for air ambulance operations to be equipped with a Helicopter Terrain Awareness and Warning System (HTAWS) that meets specific technical standards (TSO-C194 and RTCA DO-309). This requirement has been in effect since April 24, 2017.

The HTAWS equipment must have corresponding procedures in the helicopter's flight manual covering how to use the system and how crews should respond to its audio and visual warnings. This ensures pilots know how to properly react when the system alerts them to terrain threats.

In practice, HTAWS provides critical safety protection for air ambulance operations, which often involve flying at night, in poor weather, and into unfamiliar landing zones. The system warns pilots of potential terrain conflicts, helping prevent controlled flight into terrain (CFIT) accidents. Certificate holders using HTAWS equipment with FAA-approved deviations from the standard requirements still meet this regulation's intent.

*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.*