The warning tone volume control is fixed and cannot be changed.

• A. Fixed and cannot be changes
• B. Variable depending on nature of CAS message
• C. Adjustable using the HDPH knob on the audio panel
• D. Adjustable using the INPH knob on the audio panel

Answer: (A)

Warning tones are kept at a constant level so they cut through cockpit noise reliably and are always noticeable, no matter how you’ve set other audio volumes. If the warning tone were adjustable, it could be set too low and be missed in a loud environment, or become annoying if set too high, which isn’t desirable for critical alerts. The control you would use for headphone or interphone audio (like the HDPH or INPH knobs) adjusts other sounds, not the warning tone itself. The system is designed so the warning tone level cannot be changed, ensuring a consistent cue every time.