Why is the GND CTL pushbutton selected to ON during preflight?
• To record preflight activities in the cockpit
If the pushbutton was not selected ON, how would the system work in automatic mode?
• ON for 5 minutes after electrical power is supplied to the aircraft• At least one engine is operating, stops 5 min after last engine shut down.
What allows the cabin PAs to be recorded?
• ACP 3 PA volume knob out and in the 12 o’clock position