The Autotune function is used to provide FMS control over which component?

• A. GPS receiver
• B. Flight data recorder
• C. The third channel of the DME transceiver
• D. Inertial navigation system

Answer: (C)

Autotune in the FMS context is about automatically tuning the DME transceiver so the system can continuously obtain DME distance information for navigation. The FMS uses this function to select the correct DME channel without manual input, keeping distance data updated as you fly and enabling accurate leg calculations and guidance. The third channel of the DME transceiver is designated for this automatic tuning control, which is why it’s the correct choice. The GPS receiver, flight data recorder, and inertial navigation system aren’t controlled by this Autotune function in the same way, since they rely on different technologies and tuning mechanisms.